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1.
Nature ; 611(7937): 780-786, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36385534

RESUMO

Enteric pathogens are exposed to a dynamic polymicrobial environment in the gastrointestinal tract1. This microbial community has been shown to be important during infection, but there are few examples illustrating how microbial interactions can influence the virulence of invading pathogens2. Here we show that expansion of a group of antibiotic-resistant, opportunistic pathogens in the gut-the enterococci-enhances the fitness and pathogenesis of Clostridioides difficile. Through a parallel process of nutrient restriction and cross-feeding, enterococci shape the metabolic environment in the gut and reprogramme C. difficile metabolism. Enterococci provide fermentable amino acids, including leucine and ornithine, which increase C. difficile fitness in the antibiotic-perturbed gut. Parallel depletion of arginine by enterococci through arginine catabolism provides a metabolic cue for C. difficile that facilitates increased virulence. We find evidence of microbial interaction between these two pathogenic organisms in multiple mouse models of infection and patients infected with C. difficile. These findings provide mechanistic insights into the role of pathogenic microbiota in the susceptibility to and the severity of C. difficile infection.


Assuntos
Clostridioides difficile , Enterococcus , Interações Microbianas , Animais , Humanos , Camundongos , Antibacterianos/farmacologia , Arginina/deficiência , Arginina/metabolismo , Clostridioides difficile/metabolismo , Clostridioides difficile/patogenicidade , Clostridioides difficile/fisiologia , Modelos Animais de Doenças , Farmacorresistência Bacteriana , Enterococcus/efeitos dos fármacos , Enterococcus/metabolismo , Enterococcus/patogenicidade , Enterococcus/fisiologia , Microbioma Gastrointestinal/efeitos dos fármacos , Intestinos/efeitos dos fármacos , Intestinos/metabolismo , Intestinos/microbiologia , Leucina/metabolismo , Ornitina/metabolismo , Virulência , Suscetibilidade a Doenças
2.
N Engl J Med ; 386(1): 11-23, 2022 01 06.
Artigo em Inglês | MEDLINE | ID: mdl-34986284

RESUMO

BACKGROUND: A single-group, phase 1-2 study indicated that eltrombopag improved the efficacy of standard immunosuppressive therapy that entailed horse antithymocyte globulin (ATG) plus cyclosporine in patients with severe aplastic anemia. METHODS: In this prospective, investigator-led, open-label, multicenter, randomized, phase 3 trial, we compared the efficacy and safety of horse ATG plus cyclosporine with or without eltrombopag as front-line therapy in previously untreated patients with severe aplastic anemia. The primary end point was a hematologic complete response at 3 months. RESULTS: Patients were assigned to receive immunosuppressive therapy (Group A, 101 patients) or immunosuppressive therapy plus eltrombopag (Group B, 96 patients). The percentage of patients who had a complete response at 3 months was 10% in Group A and 22% in Group B (odds ratio, 3.2; 95% confidence interval [CI], 1.3 to 7.8; P = 0.01). At 6 months, the overall response rate (the percentage of patients who had a complete or partial response) was 41% in Group A and 68% in Group B. The median times to the first response were 8.8 months (Group A) and 3.0 months (Group B). The incidence of severe adverse events was similar in the two groups. With a median follow-up of 24 months, a karyotypic abnormality that was classified as myelodysplastic syndrome developed in 1 patient (Group A) and 2 patients (Group B); event-free survival was 34% and 46%, respectively. Somatic mutations were detected in 29% (Group A) and 31% (Group Β) of the patients at baseline; these percentages increased to 66% and 55%, respectively, at 6 months, without affecting the hematologic response and 2-year outcome. CONCLUSIONS: The addition of eltrombopag to standard immunosuppressive therapy improved the rate, rapidity, and strength of hematologic response among previously untreated patients with severe aplastic anemia, without additional toxic effects. (Funded by Novartis and others; RACE ClinicalTrials.gov number, NCT02099747; EudraCT number, 2014-000363-40.).


Assuntos
Anemia Aplástica/terapia , Soro Antilinfocitário/uso terapêutico , Benzoatos/uso terapêutico , Ciclosporina/uso terapêutico , Hidrazinas/uso terapêutico , Terapia de Imunossupressão , Imunossupressores/uso terapêutico , Pirazóis/uso terapêutico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Anemia Aplástica/tratamento farmacológico , Anemia Aplástica/genética , Soro Antilinfocitário/efeitos adversos , Benzoatos/efeitos adversos , Ciclosporina/efeitos adversos , Quimioterapia Combinada , Feminino , Humanos , Hidrazinas/efeitos adversos , Imunossupressores/efeitos adversos , Masculino , Pessoa de Meia-Idade , Intervalo Livre de Progressão , Estudos Prospectivos , Pirazóis/efeitos adversos , Receptores de Trombopoetina/agonistas , Indução de Remissão , Adulto Jovem
3.
PLoS Genet ; 18(2): e1010063, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-35157717

RESUMO

Sexual reproduction is a complex process that contributes to differences between the sexes and divergence between species. From a male's perspective, sexual selection can optimize reproductive success by acting on the variance in mating success (pre-insemination selection) as well as the variance in fertilization success (post-insemination selection). The balance between pre- and post-insemination selection has not yet been investigated using a strong hypothesis-testing framework that directly quantifies the effects of post-insemination selection on the evolution of reproductive success. Here we use experimental evolution of a uniquely engineered genetic system that allows sperm production to be turned off and on in obligate male-female populations of Caenorhabditis elegans. We show that enhanced post-insemination competition increases the efficacy of selection and surpasses pre-insemination sexual selection in driving a polygenic response in male reproductive success. We find that after 10 selective events occurring over 30 generations post-insemination selection increased male reproductive success by an average of 5- to 7-fold. Contrary to expectation, enhanced pre-insemination competition hindered selection and slowed the rate of evolution. Furthermore, we found that post-insemination selection resulted in a strong polygenic response at the whole-genome level. Our results demonstrate that post-insemination sexual selection plays a critical role in the rapid optimization of male reproductive fitness. Therefore, explicit consideration should be given to post-insemination dynamics when considering the population effects of sexual selection.


Assuntos
Inseminação , Espermatozoides , Animais , Caenorhabditis elegans/genética , Feminino , Masculino , Reprodução/genética , Seleção Genética , Comportamento Sexual Animal/fisiologia , Espermatozoides/fisiologia
4.
Proc Natl Acad Sci U S A ; 119(46): e2209870119, 2022 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-36346845

RESUMO

Hedgehog-interacting protein (HHIP) sequesters Hedgehog ligands to repress Smoothened (SMO)-mediated recruitment of the GLI family of transcription factors. Allelic variation in HHIP confers risk of chronic obstructive pulmonary disease and other smoking-related lung diseases, but underlying mechanisms are unclear. Using single-cell and cell-type-specific translational profiling, we show that HHIP expression is highly enriched in medial habenula (MHb) neurons, particularly MHb cholinergic neurons that regulate aversive behavioral responses to nicotine. HHIP deficiency dysregulated the expression of genes involved in cholinergic signaling in the MHb and disrupted the function of nicotinic acetylcholine receptors (nAChRs) through a PTCH-1/cholesterol-dependent mechanism. Further, CRISPR/Cas9-mediated genomic cleavage of the Hhip gene in MHb neurons enhanced the motivational properties of nicotine in mice. These findings suggest that HHIP influences vulnerability to smoking-related lung diseases in part by regulating the actions of nicotine on habenular aversion circuits.


Assuntos
Habenula , Pneumopatias , Receptores Nicotínicos , Camundongos , Animais , Nicotina/farmacologia , Nicotina/metabolismo , Habenula/metabolismo , Proteínas Hedgehog/genética , Proteínas Hedgehog/metabolismo , Receptores Nicotínicos/metabolismo , Neurônios Colinérgicos/metabolismo , Pneumopatias/metabolismo
5.
Am J Pathol ; 193(11): 1694-1705, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37330004

RESUMO

CreTrp1 mice are widely used for conditional retinal pigment epithelium (RPE) gene function studies. Like other Cre/LoxP models, phenotypes in CreTrp1 mice can be affected by Cre-mediated cellular toxicity, leading to RPE dysfunction, altered morphology and atrophy, activation of innate immunity, and consequent impairment of photoreceptor function. These effects are common among the age-related alterations of RPE that feature in early/intermediate forms of age-related macular degeneration. This article characterizes Cre-mediated pathology in the CreTrp1 line to elucidate the impact of RPE degeneration on both developmental and pathologic choroidal neovascularization. Nonredundant roles of the two major components of the hypoxia-inducible factor (HIF) family of transcription regulators, HIF1α and HIF2α, were identified. Genetic ablation of Hif1a protected against Cre-induced degeneration of RPE and choroid, whereas ablation of Hif2a exacerbated this degeneration. Furthermore, HIF1α deficiency protected CreTrp1 mice against laser-induced choroidal neovascularization, whereas HIF2α deficiency exacerbated the phenotype. Cre-mediated degeneration of the RPE in CreTrp1 mice offers an opportunity to investigate the impact of hypoxia signaling in the context of RPE degeneration. These findings indicate that HIF1α promotes Cre recombinase-mediated RPE degeneration and laser-induced choroidal neovascularization, whereas HIF2α is protective.

6.
New Phytol ; 242(4): 1448-1475, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38581203

RESUMO

Research on mycorrhizal symbiosis has been slowed by a lack of established study systems. To address this challenge, we have been developing Suillus, a widespread ecologically and economically relevant fungal genus primarily associated with the plant family Pinaceae, into a model system for studying ectomycorrhizal (ECM) associations. Over the last decade, we have compiled extensive genomic resources, culture libraries, a phenotype database, and protocols for manipulating Suillus fungi with and without their tree partners. Our efforts have already resulted in a large number of publicly available genomes, transcriptomes, and respective annotations, as well as advances in our understanding of mycorrhizal partner specificity and host communication, fungal and plant nutrition, environmental adaptation, soil nutrient cycling, interspecific competition, and biological invasions. Here, we highlight the most significant recent findings enabled by Suillus, present a suite of protocols for working with the genus, and discuss how Suillus is emerging as an important model to elucidate the ecology and evolution of ECM interactions.


Assuntos
Evolução Biológica , Modelos Biológicos , Micorrizas , Micorrizas/fisiologia , Micorrizas/genética , Ecologia , Simbiose/genética , Basidiomycota/fisiologia , Basidiomycota/genética
7.
Arterioscler Thromb Vasc Biol ; 43(10): 2030-2041, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37615111

RESUMO

BACKGROUND: Impaired cholesterol efflux capacity (CEC) is a novel lipid metabolism trait associated with atherosclerotic cardiovascular disease. Mechanisms underlying CEC variation are unknown. We evaluated associations of circulating metabolites with CEC to advance understanding of metabolic pathways involved in cholesterol efflux regulation. METHODS: Participants enrolled in the MESA (Multi-Ethnic Study of Atherosclerosis) who underwent nuclear magnetic resonance metabolome profiling and CEC measurement (N=3543) at baseline were included. Metabolite associations with CEC were evaluated using standard linear regression analyses. Repeated ElasticNet and multilayer perceptron regression were used to assess metabolite profile predictive performance for CEC. Features important for CEC prediction were identified using Shapley Additive Explanations values. RESULTS: Greater CEC was significantly associated with metabolite clusters composed of the largest-sized particle subclasses of VLDL (very-low-density lipoprotein) and HDL (high-density lipoprotein), as well as their constituent apo A1, apo A2, phospholipid, and cholesterol components (ß=0.072-0.081; P<0.001). Metabolite profiles had poor accuracy for predicting in vitro CEC in linear and nonlinear analyses (R2<0.02; Spearman ρ<0.18). The most important feature for CEC prediction was race, with Black participants having significantly lower CEC compared with other races. CONCLUSIONS: We identified independent associations among CEC, the largest-sized particle subclasses of VLDL and HDL, and their constituent apolipoproteins and lipids. A large proportion of variation in CEC remained unexplained by metabolites and traditional clinical risk factors, supporting further investigation into genomic, proteomic, and phospholipidomic determinants of CEC.


Assuntos
Aterosclerose , Proteômica , Humanos , HDL-Colesterol , Lipoproteínas HDL , Colesterol , Aterosclerose/genética , Apolipoproteínas A
8.
Nurs Res ; 73(1): 81-88, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37582291

RESUMO

BACKGROUND: Chronic pain occurs in 30% of older adults. This prevalence rate is expected to increase, given the growth in the older adult population and the associated growth of chronic conditions contributing to pain. No population-based studies have provided detailed, longitudinal information on the experience of chronic pain in older adults; the pharmacological and nonpharmacological strategies that older adults use to manage their chronic pain; and the effect of chronic pain on patient-reported outcomes. OBJECTIVES: This article aims to describe the protocol for a population-based, longitudinal study focused on understanding the experience of chronic pain in older adults. The objectives are to determine the prevalence and characteristics of chronic pain; identify the pharmacological and nonpharmacological pain treatments used; evaluate for longitudinal differences in biopsychosocial factors; and examine how pain types and pain trajectories affect important patient-reported outcomes. Also included are the results of a pilot study. METHODS: A population-based sample of approximately 1,888 older adults will be recruited from the National Opinion Research Center at the University of Chicago's AmeriSpeak Panel to complete surveys at three waves: enrollment (Wave 1), 6 months (Wave 2), and 12 months (Wave 3). To determine the feasibility, a pilot test of the enrollment survey was conducted among 123 older adults. RESULTS: In the pilot study, older adults with chronic pain reported a range of pain conditions, with osteoarthritis being the most common. Participants reported an array of pharmacological and nonpharmacological pain strategies. Compared to participants without chronic pain, those with chronic pain reported lower physical and cognitive function and poorer quality of life. Data collection for the primary, longitudinal study is ongoing. DISCUSSION: This project will be the first longitudinal population-based study to examine the experience and overall effect of chronic pain in older adults. Pilot study results provide evidence of the feasibility of study methods. Ultimately, this work will inform the development of tailored interventions for older patients targeted to decrease pain and improve function and quality of life.


Assuntos
Dor Crônica , Humanos , Idoso , Dor Crônica/epidemiologia , Dor Crônica/terapia , Manejo da Dor/métodos , Estudos Longitudinais , Projetos Piloto , Qualidade de Vida
9.
Artigo em Inglês | MEDLINE | ID: mdl-38879370

RESUMO

OBJECTIVES: To describe the incidence of postoperative hypotension in patients undergoing cardiac surgery during the first 12 hours in the intensive care unit (ICU) and any relationship between hypotension and the development of acute kidney injury (AKI). DESIGN: This was a retrospective, observational cohort study. SETTING: The study took place in a single-center tertiary teaching hospital in London, UK. PARTICIPANTS: Adult patients (n = 100) who underwent elective cardiac surgery requiring intraoperative cardiopulmonary bypass between May and November 2021 were enrolled. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A hypotensive event was defined as mean arterial pressure <65 mmHg lasting at least 1 minute. Invasive blood pressure data was analyzed for the first 12 hours after surgery, and any association between postoperative hypotension and AKI was assessed. A total of 91% of patients experienced hypotension in the first 12 hours postprocedure. On average, patients experienced 9 hypotensive events, with events lasting an average of 5 minutes. A total of 16 patients (16%) developed at least stage 1 AKI. The average duration of hypotension was significantly higher in the AKI group (4.6 min [IQR 3.3, 8.0] v 8.1 min [IQR 5.2, 14.2], p = 0.029). Those suffering AKI had longer ICU and hospital stays. CONCLUSIONS: This study demonstrated that hypotension in the first 12 hours following cardiac surgery is common and prolonged hypotensive events are associated with developing AKI. This emphasizes the importance of treating hypotension aggressively and highlights a target for further research and intervention.

10.
Neurosciences (Riyadh) ; 29(1): 44-50, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38195138

RESUMO

OBJECTIVES: To explore the barriers preventing pioglitazone use in stroke survivors and primary and secondary stroke care services. METHODS: A qualitative grounded theory approached design was used to assess post-stroke diabetes treatments and to assess clinical applicability of pioglitazone as a preventive treatment to minimize its side effects (SEs) associated. Three focus groups were established with 48 participants from Scotland and Wales health board centers during January 2019 to July 2022. RESULTS: A qualitative grounded theory approached design was used to assess post-stroke diabetes treatments and to assess clinical applicability of pioglitazone as a preventive treatment to minimize its SEs associated. Three focus groups were established with 48 participants from Scotland and Wales health board centers during January 2019 to July 2022. CONCLUSION: These strategies might allow greater treatment adherence by stroke survivors and increased confidence of the health care professionals in their practice. The findings suggest that further research will be needed to facilitate wider usage of pioglitazone in treating people with stroke and health education is necessitate when using diabetes drugs post-stroke.


Assuntos
Diabetes Mellitus , Acidente Vascular Cerebral , Humanos , Pioglitazona/uso terapêutico , Comorbidade , Diabetes Mellitus/tratamento farmacológico , Diabetes Mellitus/epidemiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/tratamento farmacológico , Sobreviventes
11.
J Biol Chem ; 298(6): 101944, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-35447116

RESUMO

Mechanistic target of rapamycin (mTOR) and mTOR complex 1 (mTORC1), linchpins of the nutrient sensing and protein synthesis pathways, are present at relatively high levels in the ganglion cell layer (GCL) and retinal ganglion cells (RGCs) of rodent and human retinas. However, the role of mTORCs in the control of protein synthesis in RGC is unknown. Here, we applied the SUrface SEnsing of Translation (SUnSET) method of nascent protein labeling to localize and quantify protein synthesis in the retinas of adult mice. We also used intravitreal injection of an adeno-associated virus 2 vector encoding Cre recombinase in the eyes of mtor- or rptor-floxed mice to conditionally knockout either both mTORCs or only mTORC1, respectively, in cells within the GCL. A novel vector encoding an inactive Cre mutant (CreΔC) served as control. We found that retinal protein synthesis was highest in the GCL, particularly in RGC. Negation of both complexes or only mTORC1 significantly reduced protein synthesis in RGC. In addition, loss of mTORC1 function caused a significant reduction in the pan-RGC marker, RNA-binding protein with multiple splicing, with little decrease of the total number of cells in the RGC layer, even at 25 weeks after adeno-associated virus-Cre injection. These findings reveal that mTORC1 signaling is necessary for maintaining the high rate of protein synthesis in RGCs of adult rodents, but it may not be essential to maintain RGC viability. These findings may also be relevant to understanding the pathophysiology of RGC disorders, including glaucoma, diabetic retinopathy, and optic neuropathies.


Assuntos
Glaucoma , Células Ganglionares da Retina , Animais , Glaucoma/metabolismo , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Retina/metabolismo , Células Ganglionares da Retina/metabolismo
12.
Hum Mol Genet ; 29(22): 3706-3716, 2021 01 21.
Artigo em Inglês | MEDLINE | ID: mdl-33355362

RESUMO

Mutations in retinitis pigmentosa GTPase regulator (RPGR) cause severe retinal ciliopathy, X-linked retinitis pigmentosa. Although two major alternatively spliced isoforms, RPGRex1-19 and RPGRORF15, are expressed, the relative importance of these isoforms in disease pathogenesis is unclear. Here, we analyzed fibroblast samples from eight patients and found that all of them form longer cilia than normal controls, albeit to different degrees. Although all mutant RPGRORF15 messenger RNAs (mRNAs) are unstable, their steady-state levels were similar or higher than those in the control cells, suggesting there may be increased transcription. Three of the fibroblasts that had higher levels of mutant RPGRORF15 mRNA also exhibited significantly higher levels of RPGRex1-19 mRNA. Four samples with unaltered RPGRex1-19 levels carried mutations in RPGRORF15 that resulted in this isoform being relatively less stable. Thus, in all cases, the RPGRex1-19/RPGRORF15 isoform ratio was increased, and this was highly correlative to the cilia extension defect. Moreover, overexpression of RPGRex1-19 (mimicking the increase in RPGRex1-19 to RPGRORF15 isoform ratio) or RPGRORF15 (mimicking reduction of the ratio) resulted in significantly longer or shorter cilia, respectively. Notably, the cilia length defect appears to be attributable to both the loss of the wild-type RPGRORF15 protein and to the higher levels of the RPGRex1-19 isoform, indicating that the observed defect is due to the altered isoform ratios. These results suggest that maintaining the optimal RPGRex1-9 to RPGRORF15 ratio is critical for cilia growth and that designing strategies that focus on the best ways to restore the RPGRex1-19/RPGRORF15 ratio may lead to better therapeutic outcomes.


Assuntos
Proteínas do Olho/genética , Doenças Genéticas Ligadas ao Cromossomo X/genética , Retinose Pigmentar/genética , Processamento Alternativo/genética , Proteínas de Transporte/genética , Cílios/genética , Cílios/patologia , Éxons/genética , Feminino , Fibroblastos , Doenças Genéticas Ligadas ao Cromossomo X/patologia , Humanos , Masculino , Mutação/genética , Isoformas de Proteínas/genética , Retina/metabolismo , Retina/patologia , Retinose Pigmentar/patologia
13.
Mult Scler ; 29(6): 691-701, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36507671

RESUMO

BACKGROUND: We evaluated imaging features suggestive of neurodegeneration within the brainstem and upper cervical spinal cord (UCSC) in non-progressive multiple sclerosis (MS). METHODS: Standardized 3-Tesla three-dimensional brain magnetic resonance imaging (MRI) studies were prospectively acquired. Rates of change in volume, surface texture, curvature were quantified at the pons and medulla-UCSC. Whole and regional brain volumes and T2-weighted lesion volumes were also quantified. Independent regression models were constructed to evaluate differences between those of Black or African ancestry (B/AA) and European ancestry (EA) with non-progressive MS. RESULTS: 209 people with MS (pwMS) having at least two MRI studies, 29% possessing 3-6 timepoints, resulted in 487 scans for analysis. Median follow-up time between MRI timepoints was 1.33 (25th-75th percentile: 0.51-1.98) years. Of 183 non-progressive pwMS, 88 and 95 self-reported being B/AA and EA, respectively. Non-progressive pwMS demonstrated greater rates of decline in pontine volume (p < 0.0001) in B/AA and in medulla-UCSC volume (p < 0.0001) for EA pwMS. Longitudinal surface texture and curvature changes suggesting reduced tissue integrity were observed at the ventral medulla-UCSC (p < 0.001), dorsal pons (p < 0.0001) and dorsal medulla (p < 0.0001) but not the ventral pons (p = 0.92) between groups. CONCLUSIONS: Selectively vulnerable regions within the brainstem-UCSC may allow for more personalized approaches to disease surveillance and management.


Assuntos
Medula Cervical , Esclerose Múltipla Recidivante-Remitente , Esclerose Múltipla , Humanos , Medula Cervical/patologia , Esclerose Múltipla/diagnóstico por imagem , Esclerose Múltipla/patologia , Negro ou Afro-Americano , Medula Espinal/diagnóstico por imagem , Medula Espinal/patologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Imageamento por Ressonância Magnética/métodos , Tronco Encefálico/diagnóstico por imagem , Esclerose Múltipla Recidivante-Remitente/patologia
14.
Liver Int ; 43(1): 139-146, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-35622445

RESUMO

BACKGROUND AND AIMS: In other forms of chronic liver disease, measurement of portal pressure is of prognostic value, but this has not yet been established in primary biliary cholangitis (PBC). The aim of the study is to determine the prognostic value of hepatic venous pressure gradient (HVPG) in relation to liver-related survival outcomes, as well as to the development of hepatic decompensation, oesophageal varices and variceal bleeding. METHODS: Baseline HVPG and liver biopsies were obtained in 86 patients followed for 10 years in a controlled trial of colchicine treatment, and subsequently in a long-term observational cohort study for a further 30 years. RESULTS: There were 49 Hepatic deaths in addition to 10 Liver Transplants (Hepatic death/transplant; n = 59). Some of these were associated with a significant variceal bleed within 3 months of death or transplant (Portal hypertension-associated death or transplant; n = 19). There were 63 deaths from all causes. During follow-up, oesophageal varices developed in 26 patients, whilst 17 bled from varices and 32 developed hepatic decompensation over a median follow-up of 18.1 years (1.9-28.5). Baseline HVPG was highly predictive of all 6 clinical outcomes and contributed significant predictive information additional to that provided by Mayo score and Ludwig stage. CONCLUSION: Measurement of baseline portal pressure is of significant prognostic value in primary biliary cholangitis.


Assuntos
Varizes Esofágicas e Gástricas , Cirrose Hepática Biliar , Humanos , Varizes Esofágicas e Gástricas/complicações , Prognóstico , Pressão na Veia Porta , Cirrose Hepática/complicações , Cirrose Hepática Biliar/complicações , Hemorragia Gastrointestinal/complicações
15.
EMBO Rep ; 22(11): e53732, 2021 11 04.
Artigo em Inglês | MEDLINE | ID: mdl-34494703

RESUMO

Neuronal communication is typically mediated via synapses and gap junctions. New forms of intercellular communication, including nanotubes (NTs) and extracellular vesicles (EVs), have been described for non-neuronal cells, but their role in neuronal communication is not known. Recently, transfer of cytoplasmic material between donor and host neurons ("material transfer") was shown to occur after photoreceptor transplantation. The cellular mechanism(s) underlying this surprising finding are unknown. Here, using transplantation, primary neuronal cultures and the generation of chimeric retinae, we show for the first time that mammalian photoreceptor neurons can form open-end NT-like processes. These processes permit the transfer of cytoplasmic and membrane-bound molecules in culture and after transplantation and can mediate gain-of-function in the acceptor cells. Rarely, organelles were also observed to transfer. Strikingly, use of chimeric retinae revealed that material transfer can occur between photoreceptors in the intact adult retina. Conversely, while photoreceptors are capable of releasing EVs, at least in culture, these are taken up by glia and not by retinal neurons. Our findings provide the first evidence of functional NT-like processes forming between sensory neurons in culture and in vivo.


Assuntos
Vesículas Extracelulares , Nanotubos , Animais , Comunicação Celular , Mamíferos , Neurônios , Retina
16.
Biol Lett ; 19(1): 20220443, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36693425

RESUMO

Eco-evolutionary theory has brought an interest in the rapid evolution of functional traits. Among them, diet is an important determinant of ecosystem structure, affecting food web dynamics and nutrient cycling. However, it is largely unknown whether diet, or diet preference, has a hereditary basis and can evolve on contemporary timescales. Here, we study the diet preferences of Trinidadian guppies Poecilia reticulata collected from directly below an introduction site of fish transplanted from a high-predation environment into a low predation site where their densities and competition increased. Behavioural assays on F2 common garden descendants of the ancestral and derived populations showed that diet preference has rapidly evolved in the introduced population in only 12 years (approx. 36 generations). Specifically, we show that the preference for high-quality food generally found in high-predation guppies is lost in the newly derived low-predation population, who show an inertia toward the first encountered food. This result is predicted by theory stating that organisms should evolve less selective diets under higher competition. Demonstrating that diet preference can show rapid and adaptive evolution is important to our understanding of eco-evolutionary feedbacks and the role of evolution in ecosystem dynamics.


Assuntos
Ecossistema , Poecilia , Animais , Evolução Biológica , Dieta , Comportamento Predatório
17.
Br J Anaesth ; 130(5): 567-572, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36868965

RESUMO

BACKGROUND: Postoperative cognitive dysfunction (POCD) is a concern after anaesthesia and surgery, but preoperative discussion of neurocognitive risks with older patients rarely occurs. Anecdotal experiences of POCD are common in the popular media and may inform patient perspectives. However, the degree of alignment between lay and scientific perspectives on POCD is not known. METHODS: We performed inductive qualitative thematic analysis on website user comments publicly submitted under an article entitled, 'The hidden long-term risks of surgery: "It gives people's brains a hard time"', published by the UK-based news source The Guardian in April 2022. RESULTS: We analysed 84 comments from 67 unique users. Themes that emerged from user comments included the importance of functional impact ('Couldn't work … even reading was a struggle'), attribution to a range of causes but particularly the use of general, rather than consciousness-preserving, anaesthesia techniques ('side effects aren't fully understood'), and inadequate preparation and response by healthcare providers ('I would have benefited by being warned'). CONCLUSIONS: There is misalignment between professional and lay understandings of POCD. Lay people emphasise subjective and functional impact of symptoms, and express beliefs about the role of anaesthetics in causing POCD. Some patients and caregivers affected by POCD report feeling abandoned by medical providers. In 2018, new nomenclature for postoperative neurocognitive disorders was published, which better aligns with lay perspectives by including subjective complaints and functional decline. Further studies based on newer definitions and public messaging may improve concordance between different understandings of this postoperative syndrome.


Assuntos
Anestesia , Anestésicos , Complicações Cognitivas Pós-Operatórias , Humanos , Complicações Cognitivas Pós-Operatórias/etiologia , Complicações Pós-Operatórias/diagnóstico , Encéfalo , Anestesia/efeitos adversos
18.
Xenobiotica ; 53(4): 223-230, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-37194558

RESUMO

Glutathione S-transferases (GSTs) are conjugating enzymes involved in drug metabolism, antioxidant defence, and cell signalling. Herein, we investigated hepatic GST conjugation in several mouse and rat strains, including both sexes, with a direct comparison to humans.Using general and isoform-selective substrates, all mouse strains had significantly greater activities than humans for total cytosolic GST, GST-M, GST-T, and microsomal GST activities. Some strains had significantly greater GST-P activities compared to humans. Sex differences between males and females were evident in all strains for total cytosolic GST, GST-M, and GST-P, and sex differences in GST-T and microsomal GST activities within strains were noted.All rats had significantly greater activities than humans for GST-M and GST-T; only some strains were significantly greater than humans for GST-P, total cytosolic GST, and microsomal GST. Sex differences within strains showed significantly greater GST-M and GST-T activities in males compared to females. Select strains showed sex differences for total cytosolic and microsomal GST activities; there were no sex differences in GST-P activities.Significant differences in glutathione conjugation between humans and rodents exist, including sex differences. This highlights the need for careful animal selection in pre-clinical studies where GSTs are the primary metabolic pathway.


Assuntos
Glutationa Transferase , Roedores , Masculino , Feminino , Humanos , Ratos , Camundongos , Animais , Roedores/metabolismo , Especificidade da Espécie , Glutationa Transferase/metabolismo , Fígado/metabolismo , Glutationa
19.
Int Rev Psychiatry ; 35(3-4): 234-241, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37267034

RESUMO

Identity is a complex concept that can be informed by various factors, involving biological, psychological, experiential, and social influences. Specifically, one's social identity refers to the ways in which individuals can adopt attributes from established collective categories, like cultural identities, ethnic identities, gender identities, and class identities, amongst others. Social identity can encompass unique and diverse interactions at an individual level, known as micro-identities, that may be selectively expressed, hidden, or downplayed, contingent on distinct sociocultural settings. However, the formation of social identity is recurrently defined in opposition to perceptions of the Other, which can entail adverse paradigms of marginalisation, stigma, and discrimination. Although this theory of Otherness has been developed across different fields, particularly sociology, it may be important in psychiatric contexts as it can engender inherent risk factors and mental health inequalities. Consequently, this paper seeks to bring attention towards these issues, exploring the construction of Otherness and its detrimental outcomes for psychiatry, such as systemic discrimination and disparities in therapeutic support, alongside recommended initiatives to mitigate against the effects of Otherness. This may require multifactorial approaches that include cultural competency training, interventions informed by micro-identities and intersectionality, patient advocacy, and structural changes to mental health policy.


Assuntos
Identidade de Gênero , Identificação Social , Humanos , Estigma Social , Saúde Mental , Fatores de Risco
20.
Mar Drugs ; 21(6)2023 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-37367692

RESUMO

Marinolides A and B, two new 24- and 26-membered bacterial macrolactones, were isolated from the marine-derived actinobacterium AJS-327 and their stereostructures initially assigned by bioinformatic data analysis. Macrolactones typically possess complex stereochemistry, the assignments of which have been one of the most difficult undertakings in natural products chemistry, and in most cases, the use of X-ray diffraction methods and total synthesis have been the major methods of assigning their absolute configurations. More recently, however, it has become apparent that the integration of bioinformatic data is growing in utility to assign absolute configurations. Genome mining and bioinformatic analysis identified the 97 kb mld biosynthetic cluster harboring seven type I polyketide synthases. A detailed bioinformatic investigation of the ketoreductase and enoylreductase domains within the multimodular polyketide synthases, coupled with NMR and X-ray diffraction data, allowed for the absolute configurations of marinolides A and B to be determined. While using bioinformatics to assign the relative and absolute configurations of natural products has high potential, this method must be coupled with full NMR-based analysis to both confirm bioinformatic assignments as well as any additional modifications that occur during biosynthesis.


Assuntos
Produtos Biológicos , Policetídeo Sintases , Policetídeo Sintases/genética , Macrolídeos/química , Biologia Computacional , Bactérias
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