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Meditation, yoga, guided imagery, and progressive relaxation are promoted as complementary approaches for health and wellbeing in the United States, but their uptake by different sociodemographic groups is unclear. This study assessed the prevalence and 20 year trends in the use of these practices in US adults between 2002-2022. We examined practice use and associations with sociodemographic and health factors in a population-weighted analysis of n = 134,959 participants across 5 cycles of the National Health Interview Survey. The overall use of meditation (18.3%, 60.53 million), yoga (16.8%, 55.78 million) and guided imagery/progressive relaxation (6.7%, 22.22 million) increased significantly from 2002 to 2022. Growth was consistent across most sociodemographic and health strata, however users of 'Other' race (comprising 54% Indigenous Americans, Odds Ratios; ORs = 1.28-1.70) and users with moderate (ORs = 1.19-1.29) psychological distress were overrepresented across all practices, and those with severe psychological distress were overrepresented in meditation (OR = 1.33) and guided imagery/progressive relaxation (OR = 1.42). Meditation use has accelerated over time for 65 + year olds (OR = 4.22), people not accessing mental health care (OR = 1.39), and less educated (OR = 4.02) groups, potentially reflecting unmet health needs. Health professionals should consider the extensive use of complementary practices in service and treatment planning and consider their risks and benefits.
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Meditação , Yoga , Humanos , Yoga/psicologia , Masculino , Feminino , Adulto , Estados Unidos/epidemiologia , Pessoa de Meia-Idade , Prevalência , Idoso , Adulto Jovem , Adolescente , Terapia de Relaxamento/métodos , Imagens, PsicoterapiaRESUMO
Coronaviruses (CoV) rewire host protein homeostasis (proteostasis) networks through interactions between viral nonstructural proteins (nsps) and host factors to promote infection. With the emergence of SARS-CoV-2, it is imperative to characterize host interactors shared across nsp homologs. Using quantitative proteomics and functional genetic screening, we identify conserved proteostasis interactors of nsp2 and nsp4 that serve pro-viral roles during infection of murine hepatitis virus - a model betacoronavirus. We uncover a glycoprotein quality control factor, Malectin (MLEC), which significantly reduces infectious titers when knocked down. During infection, nsp2 interacts with MLEC-associated proteins and the MLEC-interactome is drastically altered, stabilizing association with the Oligosaccheryltransferase (OST) complex, a crucial component of viral glycoprotein production. MLEC promotes viral protein levels and genome replication through its quality control activity. Lastly, we show MLEC promotes SARS-CoV-2 replication. Our results reveal a role for MLEC in mediating CoV infection and identify a potential target for pan-CoV antivirals.
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BACKGROUND: Trauma plays an important role in the development of psychosis, but no studies have investigated whether a trauma-focused therapy could prevent psychosis. AIMS: This study aimed to establish whether it would be feasible to conduct a multicentre randomised controlled trial (RCT) to prevent psychosis in people with an at-risk mental state (ARMS), using eye-movement desensitisation and reprocessing therapy (EMDR). METHOD: This started as a mixed-method randomised study comparing EMDR to treatment as usual but, as a result of low participant recruitment, was changed to a single-arm feasibility study. The proposed primary outcome for an RCT was transition to psychosis at 12-month follow-up. Data on secondary outcomes were also collected. Qualitative interviews were conducted with patients and therapists. RESULTS: Fourteen participants were recruited from the Early Intervention teams. Most people who expressed an interest in taking part attended an assessment to determine eligibility. All those eligible consented to take part. A total of 64% (7 of 11) of participants who were offered EMDR were followed up at 12 months. Of the 11 participants offered EMDR, one (11%, 95% CI: 0.2%, 48%) transitioned to psychosis. Nine patients and three therapists were interviewed. Participants who completed therapy (n = 4; mean 10.5 sessions) found EMDR helpful, but those who discontinued (n = 6; mean 5.2 sessions) said it had not benefitted them overall. Therapists said EMDR could be effective, although not for all patients. CONCLUSIONS: Future studies recruiting people with an ARMS to an RCT may need to extend recruitment beyond Early Intervention teams. Although some individuals found EMDR helpful, reasons for discontinuing need to be addressed in future studies.
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BACKGROUND: Due to interindividual variation in the cellular composition of the human cortex, it is essential that covariates that capture these differences are included in epigenome-wide association studies using bulk tissue. As experimentally derived cell counts are often unavailable, computational solutions have been adopted to estimate the proportion of different cell types using DNA methylation data. Here, we validate and profile the use of an expanded reference DNA methylation dataset incorporating two neuronal and three glial cell subtypes for quantifying the cellular composition of the human cortex. RESULTS: We tested eight reference panels containing different combinations of neuronal- and glial cell types and characterised their performance in deconvoluting cell proportions from computationally reconstructed or empirically derived human cortex DNA methylation data. Our analyses demonstrate that while these novel brain deconvolution models produce accurate estimates of cellular proportions from profiles generated on postnatal human cortex samples, they are not appropriate for the use in prenatal cortex or cerebellum tissue samples. Applying our models to an extensive collection of empirical datasets, we show that glial cells are twice as abundant as neuronal cells in the human cortex and identify significant associations between increased Alzheimer's disease neuropathology and the proportion of specific cell types including a decrease in NeuNNeg/SOX10Neg nuclei and an increase of NeuNNeg/SOX10Pos nuclei. CONCLUSIONS: Our novel deconvolution models produce accurate estimates for cell proportions in the human cortex. These models are available as a resource to the community enabling the control of cellular heterogeneity in epigenetic studies of brain disorders performed on bulk cortex tissue.
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Metilação de DNA , Epigênese Genética , Feminino , Gravidez , Recém-Nascido , Humanos , Neuroglia , Córtex Cerebral , Neurônios/metabolismoRESUMO
Coronaviruses (CoV), including SARS-CoV-2, modulate host proteostasis through the activation of stress-responsive signaling pathways such as the Unfolded Protein Response (UPR), which remedies misfolded protein accumulation by attenuating translation and increasing protein folding capacity. While CoV nonstructural proteins (nsps) are essential for infection, little is known about the role of nsps in modulating the UPR. We characterized the impact of overexpression of SARS-CoV-2 nsp4, a key driver of replication, on the UPR in cell culture using quantitative proteomics to sensitively detect pathway-wide upregulation of effector proteins. We find that nsp4 preferentially activates the ATF6 and PERK branches of the UPR. Previously, we found that an N-terminal truncation of nsp3 (nsp3.1) can suppress pharmacological ATF6 activation. To determine how nsp3.1 and nsp4 tune the UPR, their coexpression demonstrated that nsp3.1 suppresses nsp4-mediated PERK, but not ATF6 activation. Reanalysis of SARS-CoV-2 infection proteomics data revealed time-dependent activation of PERK targets early in infection, which subsequently fades. This temporal regulation suggests a role for nsp3 and nsp4 in tuning the PERK pathway to attenuate host translation beneficial for viral replication while avoiding later apoptotic signaling caused by chronic activation. This work furthers our understanding of CoV-host proteostasis interactions and highlights the power of proteomic methods for systems-level analysis of the UPR.
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COVID-19 , SARS-CoV-2 , Humanos , Proteômica , Resposta a Proteínas não Dobradas , Técnicas de Cultura de CélulasRESUMO
Mupirocin is a clinically important antibiotic produced by a trans-AT Type I polyketide synthase (PKS) in Pseudomonas fluorescens. The major bioactive metabolite, pseudomonic acid A (PA-A), is assembled on a tetrasubstituted tetrahydropyran (THP) core incorporating a 6-hydroxy group proposed to be introduced by α-hydroxylation of the thioester of the acyl carrier protein (ACP) bound polyketide chain. Herein, we describe an in vitro approach combining purified enzyme components, chemical synthesis, isotopic labelling, mass spectrometry and NMR in conjunction with in vivo studies leading to the first characterisation of the α-hydroxylation bimodule of the mupirocin biosynthetic pathway. These studies reveal the precise timing of hydroxylation by MupA, substrate specificity and the ACP dependency of the enzyme components that comprise this α-hydroxylation bimodule. Furthermore, using purified enzyme, it is shown that the MmpA KS0 shows relaxed substrate specificity, suggesting precise spatiotemporal control of in trans MupA recruitment in the context of the PKS. Finally, the detection of multiple intermodular MupA/ACP interactions suggests these bimodules may integrate MupA into their assembly.
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Mupirocina , Policetídeo Sintases , Policetídeo Sintases/metabolismo , Hidroxilação , Antibacterianos/químicaRESUMO
Histone modifications are critical for regulating chromatin structure and gene expression. Dysregulation of histone modifications likely contributes to disease states and cancer. Depletion of the chromatin-binding protein BRWD3 (Bromodomain and WD repeat-containing protein 3), a known substrate-specificity factor of the Cul4-DDB1 E3 ubiquitin ligase complex, results in increased H3K4me1 (H3 lysine 4 monomethylation) levels. The underlying mechanism linking BRWD3 and H3K4 methylation, however, has yet to be defined. Here, we show that depleting BRWD3 not only causes an increase in H3K4me1 levels but also causes a decrease in H3K4me3 (H3 lysine 4 trimethylation) levels, indicating that BRWD3 influences H3K4 methylation more broadly. Using immunoprecipitation coupled to quantitative mass spectrometry, we identified an interaction between BRWD3 and the H3K4-specific lysine demethylase 5 (KDM5/Lid), an enzyme that removes tri- and dimethyl marks from H3K4. Moreover, analysis of ChIP-seq (chromatin immunoprecipitation sequencing) data revealed that BRWD3 and KDM5 are significantly colocalized throughout the genome and H3K4me3 are highly enriched at BRWD3 binding sites. We show that BRWD3 promotes K48-linked polyubiquitination and degradation of KDM5 and that KDM5 degradation is dependent on both BRWD3 and Cul4. Critically, depleting KDM5 fully restores altered H3K4me3 levels and partially restores H3K4me1 levels upon BRWD3 depletion. Together, our results demonstrate that BRWD3 regulates KDM5 activity to balance H3K4 methylation levels.
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Lisina , Processamento de Proteína Pós-Traducional , Cromatina , Código das Histonas , Metilação , Drosophila , AnimaisRESUMO
Introduction: Malrotation of the intestinal tract is a congenital malformation commonly found either incidentally or after affected individuals develop signs and symptoms of intestinal obstruction. Malrotation is prone to midgut volvulus that can cause intestinal obstruction and lead to ischemia and necrosis requiring emergent surgical intervention. Rare instances of in utero midgut volvulus have been reported in the literature and carry a high mortality given the difficulty in establishing a diagnosis prior to development of signs of intestinal ischemia and necrosis. Advancements in imaging have made it possible to diagnose in utero malrotation earlier, raising the question of optimal timing of delivery, especially in cases of prenatally diagnosed midgut volvulus. In these cases, the risks of premature birth must be weighed against the risks of fetal intestinal ischemia and potential fetal demise. Case presentation: This case report details an interesting presentation of intestinal malrotation with suspected midgut volvulus found on prenatal imaging at 33 weeks and 4 days' gestation. This prompted delivery of the infant at 34 weeks and 2 days' gestation with urgent operative management, within 3 hours of life, after diagnosis was confirmed postnatally. Intraoperatively, the infant was confirmed to have midgut volvulus without bowel ischemia, the intestines were reduced, and a Ladd procedure was performed without incident. The infant recovered postoperatively without complication, tolerated advancement to full volume feeds and was discharged on day of life 18. Conclusion: Successful management of fetal malrotation with midgut volvulus may be accomplished by early access to a multi-disciplinary team of professionals, prompt postnatal confirmation of diagnosis, and urgent correction to minimize the risk of complications.
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Objective: Traumatic experiences and post-traumatic stress disorder (PTSD) are common in schizophrenia. However, few studies screening for PTSD have established the temporality of PTSD-related traumatic events to psychosis onset. Furthermore, it is unclear how many patients attribute a trauma-based contribution to their psychosis or would find trauma-focused therapy acceptable. We examine the prevalence and timing of trauma in psychosis, as well as patient views on the relationship between their trauma experiences and mental health difficulties, and on receiving trauma-focused therapy. Methods: Sixty-eight patients with an at-risk mental state (ARMS) or psychotic disorder in a UK secondary-care setting completed self-report measures of trauma and PTSD, and undertook research interviews. Proportions and odds ratios were derived with 95% confidence intervals. Results: We recruited 68 participants (estimated response rate 62%; psychotic disorder n = 61, ARMS n = 7). Sixty three (95%) reported traumatic events and 32 (47%) reported childhood abuse. Twenty-six individuals (38%) met criteria for PTSD, though for >95% this was not recorded in their notes, and 25 (37%) had sub-threshold PTSD. For 69% of participants, their worst trauma occurred before the onset of their psychosis symptoms. Most (65%) believed their psychosis symptoms were related to past traumas and 82% of these were interested in receiving trauma-focused therapy. Conclusions: PTSD is common in and often pre-dates onset of psychosis. Most patients believe their symptoms and traumas are related and would be interested in trauma-focused therapy if available. Studies evaluating the effectiveness of trauma-focused therapies for those with or at high-risk of psychosis are required.
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ABSTRACT: Mindfulness apps are becoming popular treatments for chronic pain and mental health, despite mixed evidence supporting their efficacy. Furthermore, it is unclear whether improvements in pain are due to mindfulness-specific effects or placebo effects because no trials have compared mindfulness against a sham control. The objective of this study was to compare mindfulness against 2 sham conditions with differing proximity to mindfulness to characterize the relative contributions of mindfulness-specific and nonspecific processes on chronic pain. We assessed changes in pain intensity and unpleasantness and mindfulness-specific and nonspecific pain-related processes in 169 adults with chronic or recurrent pain randomized to receive a single 20-minute online session of mindfulness, specific sham mindfulness, general sham mindfulness, or audiobook control. Mindfulness was not superior to shams for reducing pain intensity or unpleasantness, and no differential engagement of theorized mindfulness-specific processes was observed. However, mindfulness and both shams reduced pain unpleasantness relative to audiobook control, with expectancy most strongly associated with this effect. Sham specificity had no influence on expectancy or credibility ratings, pain catastrophizing, or pain effects. These findings suggest that improvements in chronic pain unpleasantness following a single session of online-delivered mindfulness meditation may be driven by placebo effects. Nonspecific treatment effects including placebo expectancy and pain catastrophizing may drive immediate pain attenuation rather than theorized mindfulness-specific processes themselves. Further research is needed to understand whether mindfulness-specific effects emerge after longer durations of online training.
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Dor Crônica , Atenção Plena , Adulto , Humanos , Dor Crônica/terapia , Efeito Placebo , Atenção Plena/métodos , Manejo da Dor/métodos , Medição da DorRESUMO
Coronaviruses (CoV), including SARS-CoV-2, modulate host proteostasis through activation of stress-responsive signaling pathways such as the Unfolded Protein Response (UPR), which remedies misfolded protein accumulation by attenuating translation and increasing protein folding capacity. While CoV nonstructural proteins (nsps) are essential for infection, little is known about the role of nsps in modulating the UPR. We characterized the impact of SARS-CoV-2 nsp4, a key driver of replication, on the UPR using quantitative proteomics to sensitively detect pathway-wide upregulation of effector proteins. We find nsp4 preferentially activates the ATF6 and PERK branches of the UPR. Previously, we found an N-terminal truncation of nsp3 (nsp3.1) can suppress pharmacological ATF6 activation. To determine how nsp3.1 and nsp4 tune the UPR, their co-expression demonstrated that nsp3.1 suppresses nsp4-mediated PERK, but not ATF6 activation. Re-analysis of SARS-CoV-2 infection proteomics data revealed time-dependent activation of PERK targets early in infection, which subsequently fades. This temporal regulation suggests a role for nsp3 and nsp4 in tuning the PERK pathway to attenuate host translation beneficial for viral replication while avoiding later apoptotic signaling caused by chronic activation. This work furthers our understanding of CoV-host proteostasis interactions and highlights the power of proteomic methods for systems-level analysis of the UPR.
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Histone modifications are critical for regulating chromatin structure and gene expression. Dysregulation of histone modifications likely contributes to disease states and cancer. Depletion of the chromatin-binding protein BRWD3, a known substrate-specificity factor of the Cul4-DDB1 E3 ubiquitin ligase complex, results in increased in H3K4me1 levels. The underlying mechanism linking BRWD3 and H3K4 methylation, however, has yet to be defined. Here, we show that depleting BRWD3 not only causes an increase in H3K4me1 levels, but also causes a decrease in H3K4me3 levels, indicating that BRWD3 influences H3K4 methylation more broadly. Using immunoprecipitation coupled to quantitative mass spectrometry, we identified an interaction between BRWD3 and the H3K4-specific demethylase 5 (KDM5/Lid), an enzyme that removes tri- and di- methyl marks from H3K4. Moreover, analysis of ChIP-seq data revealed that BRWD3 and KDM5 are significantly co- localized throughout the genome and that sites of H3K4me3 are highly enriched at BRWD3 binding sites. We show that BRWD3 promotes K48-linked polyubiquitination and degradation of KDM5 and that KDM5 degradation is dependent on both BRWD3 and Cul4. Critically, depleting KDM5 fully restores altered H3K4me3 levels and partially restores H3K4me1 levels upon BRWD3 depletion. Together, our results demonstrate that BRWD3 regulates KDM5 activity to balance H3K4 methylation levels.
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INTRODUCTION: The aim of the study was to characterize the changes in fetal lung volume following fetoscopic endoluminal tracheal occlusion (FETO) that are associated with infant survival and need for extracorporeal membrane oxygenation (ECMO) in congenital diaphragmatic hernia (CDH). METHODS: Fetuses with CDH who underwent FETO at a single institution were included. CDH cases were reclassified by MRI metrics [observed-to-expected total lung volume (O/E TLV) and percent liver herniation]. The percent changes of MRI metrics after FETO were calculated. ROC-derived cutoffs of these changes were derived to predict infant survival to discharge. Regression analyses were done to determine the association between these cutoffs with infant survival and ECMO need, adjusted for site of CDH, gestational age at delivery, fetal sex, and CDH severity. RESULTS: Thirty CDH cases were included. ROC analysis demonstrated that post-FETO increases in O/E TLV had an area under the curve of 0.74 (p = 0.035) for the prediction of survival to hospital discharge; a cutoff of less than 10% was selected. Fetuses with a <10% post-FETO increase in O/E TLV had lower survival to hospital discharge [44.8% vs. 91.7%; p = 0.018] and higher ECMO use [61.1% vs. 16.7%; p = 0.026] compared to those with an O/E TLV increase ≥10%. Similar results were observed when the analyses were restricted to left-sided CDH cases. A post-FETO <10% increase in O/E TLV was independently associated with lower survival at hospital discharge (aOR: 0.073, 95% CI: 0.008-0.689; p = 0.022) and at 12 months of age (aOR: 0.091, 95% CI: 0.01-0.825; p = 0.036) as well as with higher ECMO use (aOR: 7.88, 95% CI: 1.31-47.04; p = 0.024). CONCLUSION: Fetuses with less than 10% increase in O/E TLV following the FETO procedure are at increased risk for requiring ECMO and for death in the postnatal period when adjusted for gestational age at delivery, CDH severity, and other confounders.
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Obstrução das Vias Respiratórias , Hérnias Diafragmáticas Congênitas , Gravidez , Lactente , Feminino , Humanos , Hérnias Diafragmáticas Congênitas/diagnóstico por imagem , Hérnias Diafragmáticas Congênitas/cirurgia , Hérnias Diafragmáticas Congênitas/complicações , Fetoscopia/métodos , Pulmão , Medidas de Volume Pulmonar/métodos , Cuidado Pré-Natal , Obstrução das Vias Respiratórias/complicações , Traqueia/diagnóstico por imagem , Traqueia/cirurgia , Ultrassonografia Pré-NatalRESUMO
Pleuromutilin is an antibiotic diterpenoid made by Clitopilus passeckerianus and related fungi, and it is the progenitor of a growing class of semi-synthetic antibiotics used in veterinary and human medicine. To harness the biotechnological potential of this natural product class, a full understanding of its biosynthetic pathway is essential. Previously, a linear pathway for pleuromutilin biosynthesis was established. Here we report two shunt pathways involving Pl-sdr and Pl-atf that were identified through the rational heterologous expression of combinations of pleuromutilin biosynthetic genes in Aspergillus oryzae. Three novel pleuromutilin congeners were isolated, and their antimicrobial activity was investigated, alongside that of an additional derivative produced through a semi-synthetic approach. It was observed that the absence of various functional groups - 3 ketone, 11 hydroxyl group or 21 ketone - from the pleuromutilin framework affected the antibacterial activity of pleuromutilin congeners. This study expands our knowledge on the biosynthesis of pleuromutilin and provides avenues for the development of novel pleuromutilin analogues by combining synthetic biology and synthetic chemistry.
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Histones are essential for chromatin packaging, and histone supply must be tightly regulated as excess histones are toxic. To drive the rapid cell cycles of the early embryo, however, excess histones are maternally deposited. Therefore, soluble histones must be buffered by histone chaperones, but the chaperone necessary to stabilize soluble H3-H4 pools in the Drosophila embryo has yet to be identified. Here, we show that CG8223, the Drosophila homolog of NASP, is a H3-H4-specific chaperone in the early embryo. We demonstrate that, while a NASP null mutant is viable in Drosophila, NASP is a maternal effect gene. Embryos laid by NASP mutant mothers have a reduced rate of hatching and show defects in early embryogenesis. Critically, soluble H3-H4 pools are degraded in embryos laid by NASP mutant mothers. Our work identifies NASP as the critical H3-H4 histone chaperone in the Drosophila embryo.
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Chaperonas de Histonas , Histonas , Animais , Histonas/genética , Histonas/metabolismo , Chaperonas de Histonas/genética , Drosophila/genética , Drosophila/metabolismo , Cromatina , Chaperonas Moleculares/genética , Chaperonas Moleculares/metabolismoRESUMO
This study investigated the analgesic effects of a single session of mindfulness meditation (MM) and loving-kindness meditation (LKM) relative to a control. A total of 100 adults with chronic or current problematic pain completed a survey and were randomized to a 20-minute MM, LKM, or audiobook control. Co-primary outcomes of pain intensity and unpleasantness and mediators of mindfulness and self-compassion were assessed pre- and posttraining. Expectancies were assessed pretraining. Pain type (chronic vs current problematic) was a covariate. Relative to the control, higher expectancies were reported for MM and LKM (P < .001). MM (d = 0.41, P = .032) and LKM (d = 0.38, P = .027) had medium effects on pain intensity, with greater decreases than control (d = 0.05, P = .768). All conditions had small effects on unpleasantness. Mindful observing increased more within MM (d = 0.52, P = .022) and the control (d = 0.50, P = .011) than LKM (d = 0.12, P = .50); self-compassion increased more in LKM (d = 0.36, P = .042) than MM (d = 0.27, P = .201) and the control (d = 0.22, P = .249). The mediation models were nonsignificant. Pain type was a nonsignificant covariate. Overall, MM and LKM were associated with positive expectancies and small-medium pain intensity reductions, which did not differ by pain type. Although MM and LKM were associated with changes in theorized mediators, these changes did not underlie improvement.
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OBJECTIVE: In fetuses with severe congenital diaphragmatic hernia, fetal endoluminal tracheal occlusion (FETO) with balloon increases survival and reduces morbidity. Balloon removal is often scheduled electively. In urgent cases, in-utero removal is impossible and removal immediately after delivery has to occur, posing risk of death from airway obstruction. Medical staff need training in urgent removal. Ideal training method is unclear; thus, we compared the performance of two groups trained by different methods. METHODS: 24 medical students were randomly assigned to two different learning methods for removal: Group 1 (in-person lecture) and Group 2 (online video). Both methods presented the same information: endoscopic instrument set-up, anatomical landmarks for intubation, and balloon removal. All participants were evaluated using the same instruments and high-fidelity simulator, comparing time for instrument set-up and simulate balloon removal (including removal attempts). RESULTS: Group 1 took significantly less time for instrument set-up compared to Group 2 [62 (30-92) secs vs 81 (57-108) secs; p < 0.01)]; no difference in time to intubate and locate the balloon [75 (50-173) secs vs 92 (32-232) secs; p 0.42], or number of attempts. CONCLUSION: There was no difference between video training and in-person training with regards to the time taken to locate the FETO balloon in the trachea and to simulate its removal.
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Oclusão com Balão , Hérnias Diafragmáticas Congênitas , Treinamento por Simulação , Feminino , Humanos , Gravidez , Oclusão com Balão/métodos , Fetoscopia/métodos , Feto , Hérnias Diafragmáticas Congênitas/cirurgia , Traqueia/cirurgiaRESUMO
8-oxo Guanine DNA Glycosylase 1 is the initiating enzyme within base excision repair and removes oxidized guanines from damaged DNA. Since unrepaired 8-oxoG could lead to G : CâT : A transversion, base removal is of utmost importance for cells to ensure genomic integrity. For cells with elevated levels of reactive oxygen species this dependency is further increased. In the past we and others have validated OGG1 as a target for inhibitors to treat cancer and inflammation. Here, we present the optimization campaign that led to the broadly used tool compound TH5487. Based on results from a small molecule screening campaign, we performed hit to lead expansion and arrived at potent and selective substituted N-piperidinyl-benzimidazolones. Using X-ray crystallography data, we describe the surprising binding mode of the most potent member of the class, TH8535. Here, the N-Piperidinyl-linker adopts a chair instead of a boat conformation which was found for weaker analogues. We further demonstrate cellular target engagement and efficacy of TH8535 against a number of cancer cell lines.
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DNA Glicosilases , Neoplasias , Humanos , DNA Glicosilases/química , DNA Glicosilases/genética , DNA Glicosilases/metabolismo , Guanina/química , Guanina/metabolismo , Reparo do DNA , Benzimidazóis/farmacologia , Dano ao DNARESUMO
Mupirocin is a clinically important antibiotic produced by a trans-AT Type I polyketide synthase (PKS) in Pseudomonas fluorescens. The major bioactive metabolite, pseudomonic acid A (PA-A), is assembled on a tetrasubstituted tetrahydropyran (THP) core incorporating a 6-hydroxy group proposed to be introduced by α-hydroxylation of the thioester of the acyl carrier protein (ACP) bound polyketide chain. Herein, we describe an in vitro approach combining purified enzyme components, chemical synthesis, isotopic labelling, mass spectrometry and NMR in conjunction with in vivo studies leading to the first characterisation of the α-hydroxylation bimodule of the mupirocin biosynthetic pathway. These studies reveal the precise timing of hydroxylation by MupA, substrate specificity and the ACP dependency of the enzyme components that comprise this α-hydroxylation bimodule. Furthermore, using purified enzyme, it is shown that the MmpA KS0 shows relaxed substrate specificity, suggesting precise spatiotemporal control of in trans MupA recruitment in the context of the PKS. Finally, the detection of multiple intermodular MupA/ACP interactions suggests these bimodules may integrate MupA into their assembly.
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Objectives: Meta-analyses of meditation studies have revealed mixed modest evidence of benefits across a range of outcomes. However, because this evidence-base is predominantly from brief interventions, it is unclear whether it accurately reflects how contemporary meditators practice or the dose-response relationship between amount of practice and outcome. This study sought to characterize how contemporary meditators practice, examine any possible dose-response relationships between historical practice and measures of psychological wellbeing, and explore which characteristics of practice most strongly predict favorable psychological outcomes. Methods: One thousand six hundred and sixty-eight meditators (M = 1095 h practice, SD = 2365) responded to advertisements in meditation practice communities and social media. We explored associations between demographics, meditation practice characteristics, and outcomes including positive and negative affect, psychological distress, and life satisfaction in a cross-sectional study design. Results: Historical meditation practice (accumulated lifetime hours) was significantly associated with favorable psychological outcomes (|r| ranging from .18 to .28). Model fit was optimized with a generalized additive model (average increase in R 2 = 2.22), indicating non-linear effects. The strength of association between practice time and outcomes was generally strongest for approximately the first 500 h, before plateauing. Several practice types including Vipassana (as taught by S.N. Goenka) and cultivating practices (e.g. compassion, lovingkindness) were more strongly predictive of favorable psychological outcomes. Conclusions: Benefits of meditation accrue over time in a non-linear manner, and show variation based on practice context. These results highlight the importance of understanding how the benefits of meditation accrue over longer time durations than typical standardized programs. Supplementary Information: The online version contains supplementary material available at 10.1007/s12671-022-01977-6.