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1.
BJPsych Open ; 10(3): e105, 2024 May 09.
Article in English | MEDLINE | ID: mdl-38721786

ABSTRACT

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.

2.
BMC Biol ; 22(1): 17, 2024 Jan 25.
Article in English | MEDLINE | ID: mdl-38273288

ABSTRACT

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.


Subject(s)
DNA Methylation , Epigenesis, Genetic , Female , Pregnancy , Infant, Newborn , Humans , Neuroglia , Cerebral Cortex , Neurons/metabolism
3.
J Proteome Res ; 23(1): 356-367, 2024 01 05.
Article in English | MEDLINE | ID: mdl-38038604

ABSTRACT

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.


Subject(s)
COVID-19 , SARS-CoV-2 , Humans , Proteomics , Unfolded Protein Response , Cell Culture Techniques
4.
Angew Chem Int Ed Engl ; 62(47): e202312514, 2023 11 20.
Article in English | MEDLINE | ID: mdl-37768840

ABSTRACT

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.


Subject(s)
Mupirocin , Polyketide Synthases , Polyketide Synthases/metabolism , Hydroxylation , Anti-Bacterial Agents/chemistry
5.
Proc Natl Acad Sci U S A ; 120(39): e2305092120, 2023 09 26.
Article in English | MEDLINE | ID: mdl-37722046

ABSTRACT

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.


Subject(s)
Lysine , Protein Processing, Post-Translational , Chromatin , Histone Code , Methylation , Drosophila , Animals
6.
Article in English | MEDLINE | ID: mdl-37292252

ABSTRACT

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.

7.
Psychiatr Res Clin Pract ; 5(2): 51-59, 2023.
Article in English | MEDLINE | ID: mdl-37293141

ABSTRACT

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.

8.
Pain ; 164(10): 2273-2284, 2023 10 01.
Article in English | MEDLINE | ID: mdl-37310492

ABSTRACT

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.


Subject(s)
Chronic Pain , Mindfulness , Adult , Humans , Chronic Pain/therapy , Placebo Effect , Mindfulness/methods , Pain Management/methods , Pain Measurement
9.
bioRxiv ; 2023 Jun 12.
Article in English | MEDLINE | ID: mdl-37162862

ABSTRACT

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.

10.
bioRxiv ; 2023 Mar 28.
Article in English | MEDLINE | ID: mdl-37034668

ABSTRACT

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.

11.
Chem Sci ; 14(14): 3826-3833, 2023 Apr 05.
Article in English | MEDLINE | ID: mdl-37035691

ABSTRACT

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.

12.
Fetal Diagn Ther ; 50(2): 128-135, 2023.
Article in English | MEDLINE | ID: mdl-37040717

ABSTRACT

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.


Subject(s)
Airway Obstruction , Hernias, Diaphragmatic, Congenital , Pregnancy , Infant , Female , Humans , Hernias, Diaphragmatic, Congenital/diagnostic imaging , Hernias, Diaphragmatic, Congenital/surgery , Hernias, Diaphragmatic, Congenital/complications , Fetoscopy/methods , Lung , Lung Volume Measurements/methods , Prenatal Care , Airway Obstruction/complications , Trachea/diagnostic imaging , Trachea/surgery , Ultrasonography, Prenatal
13.
PLoS Genet ; 19(3): e1010682, 2023 03.
Article in English | MEDLINE | ID: mdl-36930688

ABSTRACT

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.


Subject(s)
Histone Chaperones , Histones , Animals , Histones/genetics , Histones/metabolism , Histone Chaperones/genetics , Drosophila/genetics , Drosophila/metabolism , Chromatin , Molecular Chaperones/genetics , Molecular Chaperones/metabolism
14.
J Pain Palliat Care Pharmacother ; : 1-11, 2023 Jan 09.
Article in English | MEDLINE | ID: mdl-36622873

ABSTRACT

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.

15.
Eur J Obstet Gynecol Reprod Biol ; 281: 92-98, 2023 Feb.
Article in English | MEDLINE | ID: mdl-36586211

ABSTRACT

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.


Subject(s)
Balloon Occlusion , Hernias, Diaphragmatic, Congenital , Simulation Training , Female , Humans , Pregnancy , Balloon Occlusion/methods , Fetoscopy/methods , Fetus , Hernias, Diaphragmatic, Congenital/surgery , Trachea/surgery
16.
ChemMedChem ; 18(1): e202200310, 2023 01 03.
Article in English | MEDLINE | ID: mdl-36128847

ABSTRACT

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 : C→T : 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.


Subject(s)
DNA Glycosylases , Neoplasms , Humans , DNA Glycosylases/chemistry , DNA Glycosylases/genetics , DNA Glycosylases/metabolism , Guanine/chemistry , Guanine/metabolism , DNA Repair , Benzimidazoles/pharmacology , DNA Damage
17.
Angew Chem Weinheim Bergstr Ger ; 135(47): e202312514, 2023 Nov 20.
Article in English | MEDLINE | ID: mdl-38515435

ABSTRACT

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.

18.
Mindfulness (N Y) ; 13(10): 2529-2546, 2022.
Article in English | MEDLINE | ID: mdl-36193220

ABSTRACT

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.

19.
Nat Commun ; 13(1): 5620, 2022 09 24.
Article in English | MEDLINE | ID: mdl-36153390

ABSTRACT

Alzheimer's disease (AD) is a chronic neurodegenerative disease characterized by the progressive accumulation of amyloid-beta and neurofibrillary tangles of tau in the neocortex. We profiled DNA methylation in two regions of the cortex from 631 donors, performing an epigenome-wide association study of multiple measures of AD neuropathology. We meta-analyzed our results with those from previous studies of DNA methylation in AD cortex (total n = 2013 donors), identifying 334 cortical differentially methylated positions (DMPs) associated with AD pathology including methylomic variation at loci not previously implicated in dementia. We subsequently profiled DNA methylation in NeuN+ (neuronal-enriched), SOX10+ (oligodendrocyte-enriched) and NeuN-/SOX10- (microglia- and astrocyte-enriched) nuclei, finding that the majority of DMPs identified in 'bulk' cortex tissue reflect DNA methylation differences occurring in non-neuronal cells. Our study highlights the power of utilizing multiple measures of neuropathology to identify epigenetic signatures of AD and the importance of characterizing disease-associated variation in purified cell-types.


Subject(s)
Alzheimer Disease , Neurodegenerative Diseases , Alzheimer Disease/metabolism , DNA Methylation/genetics , Epigenesis, Genetic , Humans , Neurodegenerative Diseases/genetics , Neurofibrillary Tangles/genetics , Neurofibrillary Tangles/metabolism
20.
Science ; 376(6600): 1471-1476, 2022 06 24.
Article in English | MEDLINE | ID: mdl-35737787

ABSTRACT

Oxidative DNA damage is recognized by 8-oxoguanine (8-oxoG) DNA glycosylase 1 (OGG1), which excises 8-oxoG, leaving a substrate for apurinic endonuclease 1 (APE1) and initiating repair. Here, we describe a small molecule (TH10785) that interacts with the phenylalanine-319 and glycine-42 amino acids of OGG1, increases the enzyme activity 10-fold, and generates a previously undescribed ß,δ-lyase enzymatic function. TH10785 controls the catalytic activity mediated by a nitrogen base within its molecular structure. In cells, TH10785 increases OGG1 recruitment to and repair of oxidative DNA damage. This alters the repair process, which no longer requires APE1 but instead is dependent on polynucleotide kinase phosphatase (PNKP1) activity. The increased repair of oxidative DNA lesions with a small molecule may have therapeutic applications in various diseases and aging.


Subject(s)
DNA Damage , DNA Glycosylases , DNA Repair , Oxidative Stress , Biocatalysis/drug effects , DNA Damage/drug effects , DNA Glycosylases/chemistry , DNA Glycosylases/drug effects , DNA Repair/drug effects , Enzyme Activation , Glycine/chemistry , Humans , Ligands , Oxidative Stress/genetics , Phenylalanine/chemistry , Substrate Specificity
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