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1.
bioRxiv ; 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38617242

RESUMO

Biomolecular condensates, such as the nucleoli or P-bodies, are non-membrane-bound assemblies of proteins and nucleic acids that facilitate specific cellular processes. Like eukaryotic P-bodies, the recently discovered bacterial ribonucleoprotein bodies (BR-bodies) organize the mRNA decay machinery, yet the similarities in molecular and cellular functions across species have been poorly explored. Here, we examine the functions of BR-bodies in the nitrogen-fixing endosymbiont Sinorhizobium meliloti, which colonizes the roots of compatible legume plants. Assembly of BR-bodies into visible foci in S. meliloti cells requires the C-terminal intrinsically disordered region (IDR) of RNase E, and foci fusion is readily observed in vivo, suggesting they are liquid-like condensates that form via mRNA sequestration. Using Rif-seq to measure mRNA lifetimes, we found a global slowdown in mRNA decay in a mutant deficient in BR-bodies, indicating that compartmentalization of the degradation machinery promotes efficient mRNA turnover. While BR-bodies are constitutively present during exponential growth, the abundance of BR-bodies increases upon cell stress, whereby they promote stress resistance. Finally, using Medicago truncatula as host, we show that BR-bodies enhance competitiveness during colonization and appear to be required for effective symbiosis, as mutants without BR-bodies failed to stimulate plant growth. These results suggest that BR-bodies provide a fitness advantage for bacteria during infection, perhaps by enabling better resistance against the host immune response.

2.
PLoS Genet ; 19(10): e1010776, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37871041

RESUMO

Sinorhizobium meliloti is a model alpha-proteobacterium for investigating microbe-host interactions, in particular nitrogen-fixing rhizobium-legume symbioses. Successful infection requires complex coordination between compatible host and endosymbiont, including bacterial production of succinoglycan, also known as exopolysaccharide-I (EPS-I). In S. meliloti EPS-I production is controlled by the conserved ExoS-ChvI two-component system. Periplasmic ExoR associates with the ExoS histidine kinase and negatively regulates ChvI-dependent expression of exo genes, necessary for EPS-I synthesis. We show that two extracytoplasmic proteins, LppA (a lipoprotein) and JspA (a lipoprotein and a metalloprotease), jointly influence EPS-I synthesis by modulating the ExoR-ExoS-ChvI pathway and expression of genes in the ChvI regulon. Deletions of jspA and lppA led to lower EPS-I production and competitive disadvantage during host colonization, for both S. meliloti with Medicago sativa and S. medicae with M. truncatula. Overexpression of jspA reduced steady-state levels of ExoR, suggesting that the JspA protease participates in ExoR degradation. This reduction in ExoR levels is dependent on LppA and can be replicated with ExoR, JspA, and LppA expressed exogenously in Caulobacter crescentus and Escherichia coli. Akin to signaling pathways that sense extracytoplasmic stress in other bacteria, JspA and LppA may monitor periplasmic conditions during interaction with the plant host to adjust accordingly expression of genes that contribute to efficient symbiosis. The molecular mechanisms underlying host colonization in our model system may have parallels in related alpha-proteobacteria.


Assuntos
Fabaceae , Sinorhizobium meliloti , Peptídeo Hidrolases/genética , Peptídeo Hidrolases/metabolismo , Proteínas de Bactérias/metabolismo , Fabaceae/metabolismo , Sinorhizobium meliloti/genética , Sinorhizobium meliloti/metabolismo , Simbiose/genética , Endopeptidases/genética , Transdução de Sinais/genética , Lipoproteínas/genética , Lipoproteínas/metabolismo , Regulação Bacteriana da Expressão Gênica , Polissacarídeos Bacterianos
3.
J Clin Psychiatry ; 83(5)2022 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-35980261

RESUMO

Objective: To investigate scopolamine's rapid-acting antidepressant effects using an active placebo comparator. Most prior intravenous scopolamine studies reduced depressive symptomatologies compared to saline placebo infusions within 3 days. However, the confounding effect of placebo is unknown given that only saline placebo has been used in prior studies.Methods: In this trial, 40 patients with major depressive disorder were randomized to receive single intravenous doses of either scopolamine hydrobromide (4-6 µg/kg) or glycopyrronium bromide (4 µg/kg) between August 2019 and April 2021 in Auckland, New Zealand. Glycopyrronium was chosen as the active placebo due to its similar antimuscarinic properties to scopolamine but inability to cross the blood-brain barrier. The primary mood outcome measure was the Montgomery-Åsberg Depression Rating Scale (MADRS) administered pre-infusion and 1, 3, 7, 14, 28, and 42 days post-infusion.Results: Per protocol, this trial was abandoned for futility at n = 40. While scopolamine reduced MADRS scores by 12.6 (± 8.7 SD) points at day 3, glycopyrronium showed similar reductions (11.2 ± 9.6 SD). Frequentist linear mixed models showed no antidepressant effects of scopolamine versus placebo (d = 0.17), and Bayesian mixed effect models showed moderate evidence in favor of the null hypothesis at day 3 (Bayes factor = 0.32). Participants remained well-blinded to drug allocation, with 50% of participants correctly guessing their allocation.Conclusions: The observed MADRS improvement was larger than in prior studies, but no antidepressant effects were observed. This study using an active placebo confirms recent studies demonstrating the lack of antidepressant efficacy of scopolamine.Trial Registration: Australian New Zealand Clinical Trials Registry identifier: ACTRN12619000569101.


Assuntos
Transtorno Depressivo Maior , Antidepressivos/uso terapêutico , Austrália , Teorema de Bayes , Transtorno Depressivo Maior/tratamento farmacológico , Método Duplo-Cego , Glicopirrolato/farmacologia , Glicopirrolato/uso terapêutico , Humanos , Escopolamina/uso terapêutico , Resultado do Tratamento
4.
F S Sci ; 3(2): 174-186, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35560015

RESUMO

OBJECTIVE: To study whether artificial intelligence (AI) technology can be used to discern quantitative differences in endometrial immune cells between cycle phases and between samples from women with polycystic ovary syndrome (PCOS) and non-PCOS controls. Only a few studies have analyzed endometrial histology using AI technology, and especially, studies of the PCOS endometrium are lacking, partly because of the technically challenging analysis and unavailability of well-phenotyped samples. Novel AI technologies can overcome this problem. DESIGN: Case-control study. SETTING: University hospital-based research laboratory. PATIENT(S): Forty-eight women with PCOS and 43 controls. Proliferative phase samples (26 control and 23 PCOS) and luteinizing hormone (LH) surge timed LH+ 7-9 (10 control and 16 PCOS) and LH+ 10-12 (7 control and 9 PCOS) secretory endometrial samples were collected during 2014-2019. INTERVENTION(S): None. MAIN OUTCOME MEASURE(S): Endometrial samples were stained with antibodies for CD8+ T cells, CD56+ uterine natural killer cells, CD68+ macrophages, and proliferation marker Ki67. Scanned whole slide images were analyzed with an AI deep learning model. Cycle phase differences in leukocyte counts, proliferation rate, and endometrial thickness were measured within the study populations and between the PCOS and control samples. A subanalysis of anovulatory PCOS samples (n = 11) vs. proliferative phase controls (n = 18) was also performed. RESULT(S): Automated cell counting with a deep learning model performs well for the human endometrium. The leukocyte numbers and proliferation in the endometrium fluctuate with the menstrual cycle. Differences in leukocyte counts were not observed between the whole PCOS population and controls. However, anovulatory women with PCOS presented with a higher number of CD68+ cells in the epithelium (controls vs. PCOS, median [interquartile range], 0.92 [0.75-1.51] vs. 1.97 [1.12-2.68]) and fewer leukocytes in the stroma (CD8%, 3.72 [2.18-4.20] vs. 1.44 [0.77-3.03]; CD56%, 6.36 [4.43-7.43] vs. 2.07 [0.65-4.99]; CD68%, 4.57 [3.92-5.70] vs. 3.07 [1.73-4.59], respectively) compared with the controls. The endometrial thickness and proliferation rate were comparable between the PCOS and control groups in all cycle phases. CONCLUSION(S): Artificial intelligence technology provides a powerful tool for endometrial research because it is objective and can efficiently analyze endometrial compartments separately. Ovulatory endometrium from women with PCOS did not differ remarkably from the controls, which may indicate that gaining ovulatory cycles normalizes the PCOS endometrium and enables normalization of leukocyte environment before implantation. Deviant endometrial leukocyte populations observed in anovulatory women with PCOS could be interrelated with the altered endometrial function observed in these women.


Assuntos
Anovulação , Aprendizado Profundo , Síndrome do Ovário Policístico , Anovulação/metabolismo , Inteligência Artificial , Estudos de Casos e Controles , Proliferação de Células , Endométrio , Feminino , Humanos , Contagem de Leucócitos , Hormônio Luteinizante/metabolismo , Síndrome do Ovário Policístico/metabolismo
5.
CBE Life Sci Educ ; 20(4): ar55, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34546103

RESUMO

Scientist Spotlights-curricular materials that employ the personal and professional stories of scientists from diverse backgrounds-have previously been shown to positively influence undergraduate students' relatability to and perceptions of scientists. We hypothesized that engaging students in authoring Scientist Spotlights might produce curricular materials of similar impact, as well as provide a mechanism for student involvement as partners in science education reform. To test this idea and investigate the impact of student-authored Scientist Spotlights, we developed a service-learning course in which teams of biology students partnered with an instructor to develop and implement Scientist Spotlights in a biology course. Results revealed that exposure to three or four student-authored Scientist Spotlights significantly shifted peers' perceptions of scientists in all partner courses. Interestingly, student-authored Scientist Spotlights shifted peers' relatability to scientists similarly among both white students and students of color. Further, student authors themselves showed increases in their relatability to scientists. Finally, a department-wide survey demonstrated significant differences in students' perceptions of scientist representation between courses with and without student-authored Spotlights. Results suggest that engaging students as authors of inclusive curricular materials and partners in reform is a promising approach to promoting inclusion and addressing representation in science.


Assuntos
Currículo , Estudantes , Avaliação Educacional , Humanos , Aprendizagem , Universidades
6.
Adv Radiat Oncol ; 5(5): 850-855, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33089017

RESUMO

PURPOSE: To analyze and report the long-term outcomes of intracranial arteriovenous malformations (AVM) treated with linear accelerator (LINAC)-based radiosurgery (LBRS) in the pediatric population. METHODS AND MATERIALS: A series of 34 pediatric patients (≤18 years old) who were treated between 2002 and 2016 were analyzed. All patients were treated with LBRS in a single fraction, with a median dose of 16.8 Gy to the 80% isodose line. Median age at treatment was 14.4 years (range 5.5-18.9). Median AVM volume was 2.91 mL (range 0.228-27.313). Median modified radiosurgery-based AVM score was 0.83 (range 0.18-2.96). The most common presenting symptom was intracranial hemorrhage (ICH) (n = 22, 64.7%). Nine patients underwent intervention before LBRS, which included prior embolization or resection. Seven lesions were in eloquent locations, defined as basal ganglia, thalamus, or brainstem. Cerebral angiography was done to confirm obliteration. RESULTS: Median follow-up time was 98 months (range 36-200 months). Twenty-two of the 34 lesions were obliterated (64.7%) with median time to obliteration of 37 months (range 14-79). No deaths occurred during the follow up period; however, two patients experienced ICH after treatment. Three other patients were treated for symptomatic radiation necrosis. CONCLUSIONS: Treatment of intracranial AVM with LBRS in the pediatric population is demonstrated to be safe and effective with long-term follow up.

7.
J Clin Neurosci ; 80: 242-249, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33099354

RESUMO

Glioblastoma (GBM) is a malignant cerebral neoplasm carrying poor prognosis. The importance of extent of resection (EoR) in GBM patient outcomes has been argued in the literature. Previous studies included tumors in eloquent regions of the brain. This confounds the role of EoR by including patients with intrinsically worse outcomes but will be over-represented in the reduced EoR category. In a homogenous group of patients in whom GTR was considered achievable, we investigated the effect of increasing EoR on survival. A retrospective review of 51 patients was undertaken. Quantitative, volumetric analysis of pre-operative and post-operative magnetic resonance image was compared with corresponding clinical details. The primary outcome measured was post-operative overall survival. Median overall survival was 18.3 months for GTR patients compared to 11.6 months for non-GTR (p = 0.025). Median pre-operative contrast-enhancing tumor volume for GTR patients was 54.7 cm3 and 24.9 cm3 for non-GTR. Post-operative median residual tumor volume was 1.1 cm3 in the non-GTR cohort. In multivariate analyses, GTR (HR [95% CI] = 0.973 [0.954-0.994], p = 0.00559) and increasing EoR (HR [95% CI] = 0.964 [0.944-0.985], p = 0.000665) remained predictors of survival. Centile dichotomization of EoR revealed 74% (HR [95% CI] = 0.351 [0.128-0.958], p = 0.0409) as the lowest threshold conferring statistically significant survival benefit. Where technically feasible, both GTR and EoR remained as independent prognostic factors for survival. GTR remains the gold standard for surgical treatment of GBM in patients, 74% being the minimum EoR required to confer survival benefit.


Assuntos
Neoplasias Encefálicas/diagnóstico por imagem , Neoplasias Encefálicas/cirurgia , Glioblastoma/diagnóstico por imagem , Glioblastoma/cirurgia , Procedimentos Neurocirúrgicos/métodos , Adulto , Idoso , Idoso de 80 Anos ou mais , Neoplasias Encefálicas/mortalidade , Estudos de Coortes , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Procedimentos Neurocirúrgicos/mortalidade , Prognóstico , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Carga Tumoral , Adulto Jovem
8.
Front Microbiol ; 11: 1742, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32793173

RESUMO

The rhizosphere microbiome (rhizobiome) plays a critical role in plant health and development. However, the processes by which the constituent microbes interact to form and maintain a community are not well understood. To investigate these molecular processes, we examined pairwise interactions between 11 different microbial isolates under select nutrient-rich and nutrient-limited conditions. We observed that when grown with media supplemented with 56 mM glucose, two microbial isolates were able to inhibit the growth of six other microbes. The interaction between microbes persisted even after the antagonistic microbe was removed, upon exposure to spent media. To probe the genetic basis for these antagonistic interactions, we used a barcoded transposon library in a proxy bacterium, Pseudomonas putida, to identify genes which showed enhanced sensitivity to the antagonistic factor(s) secreted by Acinetobacter sp. 02. Iron metabolism-related gene clusters in P. putida were implicated by this systems-level analysis. The supplementation of iron prevented the antagonistic interaction in the original microbial pair, supporting the hypothesis that iron limitation drives antagonistic microbial interactions between rhizobionts. We conclude that rhizobiome community composition is influenced by competition for limiting nutrients, with implications for growth and development of the plant.

9.
J Clin Neurosci ; 77: 185-190, 2020 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-32376156

RESUMO

Previous work at our institution treating arteriovenous malformation (AVM) with radiosurgery (RS) demonstrated superior nidus visualization and geometric accuracy with use of 3-dimensional rotational angiography (3DRA) compared to biplanar digital subtraction angiography. We have since adopted a unique radiosurgical protocol that utilizes 3DRA in the planning of linear accelerator (LINAC)-based RS delivered in a frameless manner. This study seeks to compare clinical outcomes between patients treated by this novel approach and those treated by our historic frame-based protocol. Clinical data were queried for all patients treated for AVM by single-fraction RS from 2003 to 2017. RICs were identified and classified as radiologic, symptomatic, or permanent. Excellent outcome was defined as nidus obliteration without intracranial hemorrhage (ICH) or symptomatic RIC. Clinical predictors of study outcomes were identified through univariate and multivariate logistic regression using backwards elimination to optimize a predictive model. 131 AVMs in 124 patients were included with a median follow-up of 88 months. 59 AVMs received frame-based RS and 72 AVMs received frameless RS. Rate of obliteration was 64% for frame-based RS and 61% for frameless RS (p = 0.70). Radiologic, symptomatic, and permanent RICs rates were 68%, 17%, and 8%, respectively, for frame-based cases, versus 40% (p < 0.01), 8% (p = 0.13), and 3% (p = 0.15), respectively, for frameless cases. Excellent outcome was achieved in 49% of frame-based cases and 53% of frameless cases (p = 0.68). These results illustrate the safety and effectiveness of frameless LINAC-based AVM RS utilizing 3DRA.


Assuntos
Malformações Arteriovenosas Intracranianas/cirurgia , Hemorragias Intracranianas/epidemiologia , Complicações Pós-Operatórias/epidemiologia , Radiocirurgia/métodos , Adolescente , Adulto , Angiografia Digital , Criança , Feminino , Humanos , Malformações Arteriovenosas Intracranianas/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Aceleradores de Partículas , Radiocirurgia/efeitos adversos , Radiocirurgia/instrumentação
10.
Int J Mol Sci ; 21(7)2020 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-32283828

RESUMO

Progestins are widely used for the treatment of gynecologic disorders and alone, or combined with an estrogen, are used as contraceptives. While their potencies, efficacies and side effects vary due to differences in structures, doses and routes of administration, little is known about their effects on the endometrial transcriptome in the presence or absence of estrogen. Herein, we assessed the transcriptome and pathways induced by progesterone (P4) and the three most commonly used synthetic progestins, medroxyprogesterone acetate (MPA), levonorgestrel (LNG), and norethindrone acetate (NETA), on human endometrial stromal fibroblasts (eSF), key players in endometrial physiology and reproductive success. While there were similar transcriptional responses, each progestin induced unique genes and biofunctions, consistent with their structural similarities to progesterone (P4 and MPA) or testosterone (LNG and NETA), involving cellular proliferation, migration and invasion. Addition of estradiol (E2) to each progestin influenced the number of differentially expressed genes and biofunctions in P4 and MPA, while LNG and NETA signatures were more independent of E2. Together, these data suggest different mechanisms of action for different progestins, with progestin-specific altered signatures when combined with E2. Further investigation is warranted for a personalized approach in different gynecologic disorders, for contraception, and minimizing side effects associated with their use.


Assuntos
Endométrio/efeitos dos fármacos , Endométrio/metabolismo , Regulação da Expressão Gênica/efeitos dos fármacos , Progesterona/farmacologia , Progestinas/farmacologia , Testosterona/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Estrogênios/metabolismo , Estrogênios/farmacologia , Feminino , Fibroblastos/efeitos dos fármacos , Fibroblastos/metabolismo , Humanos , Progesterona/química , Progestinas/química , Testosterona/química
11.
Hum Reprod ; 35(3): 617-640, 2020 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-32219408

RESUMO

STUDY QUESTION: Do seminal plasma (SP) and its constituents affect the decidualization capacity and transcriptome of human primary endometrial stromal fibroblasts (eSFs)? SUMMARY ANSWER: SP promotes decidualization of eSFs from women with and without inflammatory disorders (polycystic ovary syndrome (PCOS), endometriosis) in a manner that is not mediated through semen amyloids and that is associated with a potent transcriptional response, including the induction of interleukin (IL)-11, a cytokine important for SP-induced decidualization. WHAT IS KNOWN ALREADY: Clinical studies have suggested that SP can promote implantation, and studies in vitro have demonstrated that SP can promote decidualization, a steroid hormone-driven program of eSF differentiation that is essential for embryo implantation and that is compromised in women with the inflammatory disorders PCOS and endometriosis. STUDY DESIGN, SIZE, DURATION: This is a cross-sectional study involving samples treated with vehicle alone versus treatment with SP or SP constituents. SP was tested for the ability to promote decidualization in vitro in eSFs from women with or without PCOS or endometriosis (n = 9). The role of semen amyloids and fractionated SP in mediating this effect and in eliciting transcriptional changes in eSFs was then studied. Finally, the role of IL-11, a cytokine with a key role in implantation and decidualization, was assessed as a mediator of the SP-facilitated decidualization. PARTICIPANTS/MATERIALS, SETTING, METHODS: eSFs and endometrial epithelial cells (eECs) were isolated from endometrial biopsies from women of reproductive age undergoing benign gynecologic procedures and maintained in vitro. Assays were conducted to assess whether the treatment of eSFs with SP or SP constituents affects the rate and extent of decidualization in women with and without inflammatory disorders. To characterize the response of the endometrium to SP and SP constituents, RNA was isolated from treated eSFs or eECs and analyzed by RNA sequencing (RNAseq). Secreted factors in conditioned media from treated cells were analyzed by Luminex and ELISA. The role of IL-11 in SP-induced decidualization was assessed through Clustered regularly interspaced short palindromic repeats (CRISPR)/Cas-9-mediated knockout experiments in primary eSFs. MAIN RESULTS AND THE ROLE OF CHANCE: SP promoted decidualization both in the absence and presence of steroid hormones (P < 0.05 versus vehicle) in a manner that required seminal proteins. Semen amyloids did not promote decidualization and induced weak transcriptomic and secretomic responses in eSFs. In contrast, fractionated SP enriched for seminal microvesicles (MVs) promoted decidualization. IL-11 was one of the most potently SP-induced genes in eSFs and was important for SP-facilitated decidualization. LARGE SCALE DATA: RNAseq data were deposited in the Gene Expression Omnibus repository under series accession number GSE135640. LIMITATIONS, REASONS FOR CAUTION: This study is limited to in vitro analyses. WIDER IMPLICATIONS OF THE FINDINGS: Our results support the notion that SP promotes decidualization, including within eSFs from women with inflammatory disorders. Despite the general ability of amyloids to induce cytokines known to be important for implantation, semen amyloids poorly signaled to eSFs and did not promote their decidualization. In contrast, fractionated SP enriched for MVs promoted decidualization and induced a transcriptional response in eSFs that overlapped with that of SP. Our results suggest that SP constituents, possibly those associated with MVs, can promote decidualization of eSFs in an IL-11-dependent manner in preparation for implantation. STUDY FUNDING/COMPETING INTEREST(S): This project was supported by NIH (R21AI116252, R21AI122821 and R01AI127219) to N.R.R. and (P50HD055764) to L.C.G. The authors declare no conflict of interest.


Assuntos
Decídua , Fibroblastos/citologia , Interleucina-11/fisiologia , Sêmen , Estudos Transversais , Decídua/fisiologia , Endometriose , Endométrio/citologia , Feminino , Humanos , Interleucina-11/genética , Síndrome do Ovário Policístico
12.
Brain Topogr ; 33(3): 303-316, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32144628

RESUMO

The recent development of multiband functional magnetic resonance imaging (MB-fMRI) allows for the reduction of sampling period by simultaneously exciting multiple slices-the number of which is referred to as the multiband factor. Simultaneously recorded electroencephalography (EEG)/MB-fMRI has yet to be validated for data quality against conventional single band (SB)-fMRI. Pilot scans were conducted on phantoms twice and on a healthy volunteer to ensure no heating effects. In the main study, two thermometer probes were attached to 16 healthy individuals (ages 20-39, 9 females) whilst they completed two sets of 16-min resting-state and two sets of 9-min n-back task scans-each set consisting of one MB4 and one SB pulse sequence. No heating effects were reported and thermometer data showed mean increases of < 1.0 °C. Minimal differences between the two scan types were found in EEG channel variance and spectra. Expected decreases in MB4-fMRI tSNR were observed. In n-back task scans, little to no differences were detected in both EEG source analyses and fMRI local analyses for mixed effects. Resting-state posterior cingulate cortex seed-based analyses of the default mode network along with EEG-informed fMRI analysis of the occipital alpha anticorrelation effect showed improved statistical and spatial sensitivity at lower scan durations. Using EEG/MB4-fMRI for n-back tasks provided no statistical advantages nor disadvantages. However, for studying the resting-state, MB4-fMRI potentially allows for reduced scanning durations for equivalent statistical significance to be obtained or alternatively, larger effect sizes for the same scanning duration. As such, simultaneous EEG/MB4-fMRI is a viable alternative to EEG/SB-fMRI.


Assuntos
Mapeamento Encefálico , Eletroencefalografia , Imageamento por Ressonância Magnética , Adulto , Encéfalo/diagnóstico por imagem , Feminino , Voluntários Saudáveis , Humanos , Adulto Jovem
13.
Trials ; 21(1): 157, 2020 Feb 10.
Artigo em Inglês | MEDLINE | ID: mdl-32041658

RESUMO

BACKGROUND: Depressive disorders are a leading cause of disability, but current behavioural and pharmacological therapies have a slow onset of response, typically taking several weeks before achieving efficacy. Prior studies using triplicate intravenous scopolamine infusions have been shown to reduce depressive symptomologies within days compared to saline placebo infusions. However, several parameters of scopolamine's potential antidepressant effect remain unknown, such as its dose-response profile and its washout period. There is also the question as to whether the previously reported antidepressant responses were confounded by unblinding effects due to the lack of an active placebo control. Glycopyrronium bromide was selected as placebo for this trial given it has similar antimuscarinic properties to scopolamine hydrobromide but an inability to cross the blood-brain barrier, thereby hypothetically mimicking only the peripheral effects of scopolamine. METHODS/DESIGN: A parallel group trial of single intravenous scopolamine infusions at three doses (4, 5, and 6 µg/kg) along with one glycopyrronium bromide 4 µg/kg group will be administered to 40 participants with major depressive disorder in a 1:1:1:2 ratio, respectively. The primary outcome measure will be the Montgomery-Åsberg Depression Rating Scale (MADRS) administered at baseline, 4 hours, 1 day, 3 days, 1 week, 2 weeks, 4 weeks, and 6 weeks post-infusion to determine antidepressant efficacy. As a secondary measure, the Quick Inventory of Depressive Symptomatology will be administered alongside the MADRS to further track potential antidepressant responses. Other secondary measures include electroencephalography, blood samples, and Bowdle visual acuity scales recorded at baseline, 5, 10, 15, 20, 30, 60, 120, and 240 min post-infusion to determine the pharmacokinetic-pharmacodynamic profile of scopolamine in depressed participants. DISCUSSION: This trial contributes to the literature surrounding the efficacy of scopolamine as an antidepressant. Determining the dose-response profile and washout period of scopolamine's antidepressant effect will also provide important information for designing and conducting crossover trials. The use of an active placebo is important to reduce potentially confounding expectancy effects. TRIAL REGISTRATION: The trial was registered in the Australian New Zealand Clinical Trials Registry (registration number ACTRN12619000569101). Registered on 11 April 2019.


Assuntos
Antidepressivos/administração & dosagem , Transtorno Depressivo Maior/tratamento farmacológico , Antagonistas Muscarínicos/administração & dosagem , Escopolamina/administração & dosagem , Adolescente , Adulto , Relação Dose-Resposta a Droga , Método Duplo-Cego , Feminino , Humanos , Infusões Intravenosas , Masculino , Pessoa de Meia-Idade , Testes Neuropsicológicos , Ensaios Clínicos Controlados Aleatórios como Assunto , Resultado do Tratamento , Adulto Jovem
14.
J Biol Chem ; 295(39): 13532-13555, 2020 09 25.
Artigo em Inglês | MEDLINE | ID: mdl-31481471

RESUMO

Autosomal recessive mutations in the galactosidase ß1 (GLB1) gene cause lysosomal ß-gal deficiency, resulting in accumulation of galactose-containing substrates and onset of the progressive and fatal neurodegenerative lysosomal storage disease, GM1 gangliosidosis. Here, an enzyme replacement therapy (ERT) approach in fibroblasts from GM1 gangliosidosis patients with recombinant human ß-gal (rhß-gal) produced in Chinese hamster ovary cells enabled direct and precise rhß-gal delivery to acidified lysosomes. A single, low dose (3 nm) of rhß-gal was sufficient for normalizing ß-gal activity and mediating substrate clearance for several weeks. We found that rhß-gal uptake by the fibroblasts is dose-dependent and saturable and can be competitively inhibited by mannose 6-phosphate, suggesting cation-independent, mannose 6-phosphate receptor-mediated endocytosis from the cell surface. A single intracerebroventricularly (ICV) administered dose of rhß-gal (100 µg) resulted in broad bilateral biodistribution of rhß-gal to critical regions of pathology in a mouse model of GM1 gangliosidosis. Weekly ICV dosing of rhß-gal for 8 weeks substantially reduced brain levels of ganglioside and oligosaccharide substrates and reversed well-established secondary neuropathology. Of note, unlike with the ERT approach, chronic lentivirus-mediated GLB1 overexpression in the GM1 gangliosidosis patient fibroblasts caused accumulation of a prelysosomal pool of ß-gal, resulting in activation of the unfolded protein response and endoplasmic reticulum stress. This outcome was unsurprising in light of our in vitro biophysical findings for rhß-gal, which include pH-dependent and concentration-dependent stability and dynamic self-association. Collectively, our results highlight that ICV-ERT is an effective therapeutic intervention for managing GM1 gangliosidosis potentially more safely than with gene therapy approaches.


Assuntos
Terapia de Reposição de Enzimas , Gangliosidose GM1/terapia , beta-Galactosidase/metabolismo , Animais , Gangliosidose GM1/metabolismo , Gangliosidose GM1/patologia , Camundongos
15.
Environ Toxicol Chem ; 38(9): 1911-1922, 2019 09.
Artigo em Inglês | MEDLINE | ID: mdl-31107972

RESUMO

Advances in engineering biology have expanded the list of renewable compounds that can be produced at scale via biological routes from plant biomass. In most cases, these chemical products have not been evaluated for effects on biological systems, defined in the present study as bioactivity, that may be relevant to their manufacture. For sustainable chemical and fuel production, the industry needs to transition from fossil to renewable carbon sources, resulting in unprecedented expansion in the production and environmental distribution of chemicals used in biomanufacturing. Further, although some chemicals have been assessed for mammalian toxicity, environmental and agricultural hazards are largely unknown. We assessed 6 compounds that are representative of the emerging biofuel and bioproduct manufacturing process for their effect on model plants (Arabidopsis thaliana, Sorghum bicolor) and show that several alter plant seedling physiology at submillimolar concentrations. However, these responses change in the presence of individual bacterial species from the A. thaliana root microbiome. We identified 2 individual microbes that change the effect of chemical treatment on root architecture and a pooled microbial community with different effects relative to its constituents individually. The present study indicates that screening industrial chemicals for bioactivity on model organisms in the presence of their microbiomes is important for biologically and ecologically relevant risk analyses. Environ Toxicol Chem 2019;38:1911-1922. © 2019 The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals, Inc. on behalf of SETAC.


Assuntos
Arabidopsis/efeitos dos fármacos , Biocombustíveis , Ecotoxicologia/métodos , Rhizobium/crescimento & desenvolvimento , Poluentes do Solo/toxicidade , Sorghum/efeitos dos fármacos , Agricultura , Arabidopsis/crescimento & desenvolvimento , Biomassa , Raízes de Plantas/microbiologia , Sorghum/crescimento & desenvolvimento
16.
World Neurosurg ; 122: e1153-e1161, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30447464

RESUMO

OBJECTIVE: The role of adjuvant radiotherapy (ART) in patients with World Health Organization Grade II atypical meningiomas (AMs) remains controversial. METHODS: We retrospectively reviewed 149 patients with newly diagnosed resected AMs from 2000 to 2012. Gross total resection (GTR) was defined as Simpson Grades I-III and subtotal resection (STR) as Grades IV and V. Kaplan-Meier analyses of local control (LC), progression-free survival (PFS), and overall survival were performed with the log-rank test, and risk factors for progression/recurrence (P/R) were analyzed with multivariate Cox regression. RESULTS: Median follow-up was 74.2 months. GTR was achieved in 98 patients and STR in 51 patients. Fifty-three (35%) patients received ART. Overall, 46 patients (31%) experienced P/R with a median time to P/R of 32.4 months. ART was associated with a trend toward improved PFS (P = 0.0669) in the GTR subset but significantly improved LC (P = 0.0183) and PFS (P = 0.0034) in the STR subset. Age, tumor size, and STR were significant risk factors for worse PFS, whereas receiving ART was associated with improved PFS on multivariate analyses. Thirty-nine of the 46 progressive/recurrent patients underwent salvage therapy with only 22 patients experiencing long-term control. Five patients experienced transformation to World Health Organization Grade III malignant meningioma. CONCLUSIONS: Patients who undergo STR for newly diagnosed AM should receive ART based on improvements in LC and PFS. GTR patients should be considered for ART, but active surveillance is a reasonable management approach with the recognition that progressive/recurrent disease can act aggressively. Prospective, randomized trials are currently underway to evaluate the role of ART.


Assuntos
Neoplasias Meníngeas/diagnóstico por imagem , Neoplasias Meníngeas/radioterapia , Meningioma/diagnóstico por imagem , Meningioma/radioterapia , Radioterapia Adjuvante/tendências , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Feminino , Seguimentos , Humanos , Masculino , Neoplasias Meníngeas/mortalidade , Meningioma/mortalidade , Pessoa de Meia-Idade , Radioterapia Adjuvante/métodos , Radioterapia Adjuvante/mortalidade , Estudos Retrospectivos , Taxa de Sobrevida/tendências , Fatores de Tempo , Resultado do Tratamento , Adulto Jovem
17.
Nat Commun ; 9(1): 4596, 2018 10 30.
Artigo em Inglês | MEDLINE | ID: mdl-30375402

RESUMO

In the original version of this Article, an incorrect URL was provided in the Data Availability Statement regarding the deposition of plasmids listed in Supplementary Table 4. The correct URL is https://public-registry.jbei.org/folders/378 . This error has been corrected in both the PDF and HTML versions of the Article.

18.
Nat Commun ; 9(1): 3617, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-30190458

RESUMO

Tightly regulated promoters are essential for numerous biological applications, where strong inducibility, portability, and scalability are desirable. Current systems are often incompatible with large-scale fermentations due to high inducer costs and strict media requirements. Here, we describe the bottom-up engineering of 'Jungle Express', an expression system that enables efficient gene regulation in diverse proteobacteria. This system is guided by EilR, a multidrug-binding repressor with high affinity to its optimized operator and cationic dyes that act as powerful inducers at negligible costs. In E. coli, the engineered promoters exhibit minimal basal transcription and are inducible over four orders of magnitude by 1 µM crystal violet, reaching expression levels exceeding those of the strongest current bacterial systems. Further, we provide molecular insights into specific interactions of EilR with its operator and with two inducers. The versatility of Jungle Express opens the way for tightly controlled and efficient gene expression that is not restricted to host organism, substrate, or scale.


Assuntos
Proteínas de Bactérias/genética , Escherichia coli/genética , Engenharia Genética/métodos , Regiões Operadoras Genéticas , Proteínas Repressoras/genética , Proteínas de Bactérias/química , Proteínas de Bactérias/metabolismo , Cristalografia por Raios X , Escherichia coli/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Violeta Genciana/farmacologia , Sequências Repetidas Invertidas , Regiões Promotoras Genéticas , Proteobactérias/efeitos dos fármacos , Proteobactérias/genética , Proteínas Repressoras/metabolismo , Corantes de Rosanilina/farmacologia , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Transcrição Gênica
19.
Biol Reprod ; 99(2): 336-348, 2018 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-29518187

RESUMO

Seminal plasma (SP), the liquid fraction of semen, is not mandatory for conception, but clinical studies suggest that SP improves implantation rates. Prior in vitro studies examining the effects of SP on the endometrium, the site of implantation, surprisingly revealed that SP induces transcriptional profiles associated with neurogenesis. We investigated the presence and activity of neurogenesis pathways in the endometrium, focusing on TrkA, one of the canonical receptors associated with neurotrophic signaling. We demonstrate that TrkA is expressed in the endometrium. To determine if SP activates TrkA signaling, we isolated the two most abundant endometrial cell types-endometrial epithelial cells (eEC) and endometrial stromal fibroblasts (eSF)-and examined TrkA activity in these cells after SP exposure. While SP only moderately activated TrkA in eEC, it potently and rapidly activated TrkA in eSF. This activation occurred in both non-decidualized and decidualized eSF. Blocking this pathway resulted in dysregulation of SP-induced cytokine production by eSF. Surprisingly, while the canonical TrkA agonist nerve growth factor was detected in SP, TrkA activation was principally induced by a 30-100-kDa protein whose identity remains to be established. Our results show that TrkA signaling is highly active in eSF and is rapidly induced by SP.


Assuntos
Endométrio/metabolismo , Fibroblastos/metabolismo , Receptor trkA/metabolismo , Sêmen/metabolismo , Células Estromais/metabolismo , Adulto , Implantação do Embrião/fisiologia , Endométrio/citologia , Feminino , Fibroblastos/citologia , Humanos , Fosforilação , Transdução de Sinais/fisiologia
20.
CBE Life Sci Educ ; 17(1)2018.
Artigo em Inglês | MEDLINE | ID: mdl-29326102

RESUMO

Many efforts to improve science teaching in higher education focus on a few faculty members at an institution at a time, with limited published evidence on attempts to engage faculty across entire departments. We created a long-term, department-wide collaborative professional development program, Biology Faculty Explorations in Scientific Teaching (Biology FEST). Across 3 years of Biology FEST, 89% of the department's faculty completed a weeklong scientific teaching institute, and 83% of eligible instructors participated in additional semester-long follow-up programs. A semester after institute completion, the majority of Biology FEST alumni reported adding active learning to their courses. These instructor self-reports were corroborated by audio analysis of classroom noise and surveys of students in biology courses on the frequency of active-learning techniques used in classes taught by Biology FEST alumni and nonalumni. Three years after Biology FEST launched, faculty participants overwhelmingly reported that their teaching was positively affected. Unexpectedly, most respondents also believed that they had improved relationships with departmental colleagues and felt a greater sense of belonging to the department. Overall, our results indicate that biology department-wide collaborative efforts to develop scientific teaching skills can indeed attract large numbers of faculty, spark widespread change in teaching practices, and improve departmental relations.


Assuntos
Biologia/educação , Desenvolvimento de Programas , Ensino , Docentes , Objetivos , Humanos , Motivação , Aprendizagem Baseada em Problemas , Estudantes , Inquéritos e Questionários
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