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1.
Nucleic Acids Res ; 50(19): 11138-11153, 2022 10 28.
Artigo em Inglês | MEDLINE | ID: mdl-36259649

RESUMO

Bacteria can acquire mobile genetic elements (MGEs) to combat infection by viruses (phages). Satellite viruses, including the PLEs (phage-inducible chromosomal island-like elements) in epidemic Vibrio cholerae, are MGEs that restrict phage replication to the benefit of their host bacterium. PLEs parasitize the lytic phage ICP1, unleashing multiple mechanisms to restrict phage replication and promote their own spread. In the arms race against PLE, ICP1 uses nucleases, including CRISPR-Cas, to destroy PLE's genome during infection. However, through an unknown CRISPR-independent mechanism, specific ICP1 isolates subvert restriction by PLE. Here, we discover ICP1-encoded Adi that counteracts PLE by exploiting the PLE's large serine recombinase (LSR), which normally mobilizes PLE in response to ICP1 infection. Unlike previously characterized ICP1-encoded anti-PLE mechanisms, Adi is not a nuclease itself but instead appears to modulate the activity of the LSR to promote destructive nuclease activity at the LSR's specific attachment site, attP. The PLE LSR, its catalytic activity, and attP are additionally sufficient to sensitize a PLE encoding a resistant variant of the recombination module to Adi activity. This work highlights a unique type of adaptation arising from inter-genome conflicts, in which the intended activity of a protein can be weaponized to overcome the antagonizing genome.


Assuntos
Bacteriófagos , Vibrio cholerae , Bacteriófagos/metabolismo , Recombinases/genética , Recombinases/metabolismo , Vibrio cholerae/metabolismo , Sistemas CRISPR-Cas
2.
Bioinformatics ; 37(19): 3382-3383, 2021 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-33774657

RESUMO

SUMMARY: Multiplexed assays of variant effect (MAVEs) are capable of experimentally testing all possible single nucleotide or amino acid variants in selected genomic regions, generating 'variant effect maps', which provide biochemical insight and functional evidence to enable more rapid and accurate clinical interpretation of human variation. Because the international community applying MAVE approaches is growing rapidly, we developed the online MaveRegistry platform to catalyze collaboration, reduce redundant efforts, allow stakeholders to nominate targets and enable tracking and sharing of progress on ongoing MAVE projects. AVAILABILITY AND IMPLEMENTATION: MaveRegistry service: https://registry.varianteffect.org. MaveRegistry source code: https://github.com/kvnkuang/maveregistry-front-end.

3.
Intern Med J ; 52(5): 755-762, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-34580964

RESUMO

BACKGROUND: Conversion from paper-based to electronic medical records (EMR) may affect the quality and timeliness of the completion of Goals-of-Care (GOC) documents during hospital admissions and this may have been further impacted by the COVID-19 pandemic. AIMS: To determine the impact of EMR and COVID-19 on the proper completion of GOC forms and the factors associated with inpatient changes in GOC. METHODS: We conducted a cross-sectional study of adult general medicine admissions (August 2018-September 2020) at Dandenong Hospital (Victoria, Australia). We used interrupted time series to model the changes in the rates of proper GOC completion (adequate documented discussion, completed ≤2 days) after the introduction of EMR and the arrival of COVID-19. RESULTS: We included a total of 5147 patients. The pre-EMR GOC proper completion rate was 27.7% (overall completion, 86.5%). There was a decrease in the proper completion rate by 2.21% per month (95% confidence interval (CI): -2.83 to -1.58) after EMR implementation despite an increase in overall completion rates (91.2%). The main reason for the negative trend was a decline in adequate documentation despite improvements in timeliness. COVID-19 arrival saw a reversal of this negative trend, with proper completion rates increasing by 2.25% per month (95% CI: 1.35 to 3.15) compared with the EMR period, but also resulted in a higher proportion of GOC changes within 2 days of admission. CONCLUSIONS: EMR improved the timeliness and overall completion rates of GOC at the cost of a lower quality of documented discussion. COVID-19 reversed the negative trend in proper GOC completion but increased the number of early revisions.


Assuntos
COVID-19 , Adulto , COVID-19/epidemiologia , Estudos Transversais , Registros Eletrônicos de Saúde , Objetivos , Humanos , Pandemias , Vitória
4.
Diabetologia ; 64(11): 2517-2533, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-34392397

RESUMO

AIMS/HYPOTHESIS: This study interrogated mitochondrial respiratory function and content in skeletal muscle biopsies of healthy adults between 30 and 72 years old with and without uncomplicated type 1 diabetes. METHODS: Participants (12 women/nine men) with type 1 diabetes (48 ± 11 years of age), without overt complications, were matched for age, sex, BMI and level of physical activity to participants without diabetes (control participants) (49 ± 12 years of age). Participants underwent a Bergström biopsy of the vastus lateralis to assess mitochondrial respiratory function using high-resolution respirometry and citrate synthase activity. Electron microscopy was used to quantify mitochondrial content and cristae (pixel) density. RESULTS: Mean mitochondrial area density was 27% lower (p = 0.006) in participants with type 1 diabetes compared with control participants. This was largely due to smaller mitochondrial fragments in women with type 1 diabetes (-18%, p = 0.057), as opposed to a decrease in the total number of mitochondrial fragments in men with diabetes (-28%, p = 0.130). Mitochondrial respiratory measures, whether estimated per milligram of tissue (i.e. mass-specific) or normalised to area density (i.e. intrinsic mitochondrial function), differed between cohorts, and demonstrated sexual dimorphism. Mass-specific mitochondrial oxidative phosphorylation (OXPHOS) capacity with the substrates for complex I and complex II (CI + II) was significantly lower (-24%, p = 0.033) in women with type 1 diabetes compared with control participants, whereas mass-specific OXPHOS capacities with substrates for complex I only (pyruvate [CI pyr] or glutamate [CI glu]) or complex II only (succinate [CII succ]) were not different (p > 0.404). No statistical differences (p > 0.397) were found in mass-specific OXPHOS capacity in men with type 1 diabetes compared with control participants despite a 42% non-significant increase in CI glu OXPHOS capacity (p = 0.218). In contrast, intrinsic CI + II OXPHOS capacity was not different in women with type 1 diabetes (+5%, p = 0.378), whereas in men with type 1 diabetes it was 25% higher (p = 0.163) compared with control participants. Men with type 1 diabetes also demonstrated higher intrinsic OXPHOS capacity for CI pyr (+50%, p = 0.159), CI glu (+88%, p = 0.033) and CII succ (+28%, p = 0.123), as well as higher intrinsic respiratory rates with low (more physiological) concentrations of either ADP, pyruvate, glutamate or succinate (p < 0.012). Women with type 1 diabetes had higher (p < 0.003) intrinsic respiratory rates with low concentrations of succinate only. Calculated aerobic fitness (Physical Working Capacity Test [PWC130]) showed a strong relationship with mitochondrial respiratory function and content in the type 1 diabetes cohort. CONCLUSIONS/INTERPRETATION: In middle- to older-aged adults with uncomplicated type 1 diabetes, we conclude that skeletal muscle mitochondria differentially adapt to type 1 diabetes and demonstrate sexual dimorphism. Importantly, these cellular alterations were significantly associated with our metric of aerobic fitness (PWC130) and preceded notable impairments in skeletal mass and strength.


Assuntos
Respiração Celular/fisiologia , Diabetes Mellitus Tipo 1/metabolismo , Mitocôndrias Musculares/metabolismo , Músculo Esquelético/metabolismo , Adulto , Idoso , Complexo I de Transporte de Elétrons/metabolismo , Complexo II de Transporte de Elétrons/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Fosforilação Oxidativa , Consumo de Oxigênio/fisiologia , Mecânica Respiratória
5.
Mov Disord ; 36(12): 2719-2730, 2021 12.
Artigo em Inglês | MEDLINE | ID: mdl-34613624

RESUMO

Mutations in GBA1, which encode for the protein glucocerebrosidase (GCase), are the most common genetic risk factor for Parkinson's disease and dementia with Lewy bodies. In addition, growing evidence now suggests that the loss of GCase activity is also involved in onset of all forms of Parkinson's disease, dementia with Lewy bodies, and other dementias, such as progranulin-linked frontal temporal dementia. As a result, there is significant interest in developing GCase-targeted therapies that have the potential to stop or slow progression of these diseases. Despite this interest in GCase as a therapeutic target, there is significant inconsistency in the methodology for measuring GCase enzymatic activity in disease-modeling systems and patient populations, which could hinder progress in developing GCase therapies. In this review, we discuss the different strategies that have been developed to assess GCase activity and highlight the specific strengths and weaknesses of these approaches as well as the gaps that remain. We also discuss the current and potential role of these different methodologies in preclinical and clinical development of GCase-targeted therapies. © 2021 The Authors. Movement Disorders published by Wiley Periodicals LLC on behalf of International Parkinson and Movement Disorder Society.


Assuntos
Glucosilceramidase , Doença de Parkinson , Glucosilceramidase/genética , Glucosilceramidase/metabolismo , Humanos , Corpos de Lewy/metabolismo , Lisossomos/metabolismo , Mutação , Doença de Parkinson/terapia , alfa-Sinucleína/metabolismo
6.
Clin Sci (Lond) ; 135(15): 1859-1871, 2021 08 13.
Artigo em Inglês | MEDLINE | ID: mdl-34296277

RESUMO

BACKGROUND AND AIMS: Preterm birth is associated with increased risk of cardiovascular disease (CVD). This may reflect a legacy of inflammatory exposures such as chorioamnionitis which complicate pregnancies delivering preterm, or recurrent early-life infections, which are common in preterm infants. We previously reported that experimental chorioamnionitis followed by postnatal inflammation has additive and deleterious effects on atherosclerosis in ApoE-/- mice. Here, we aimed to investigate whether innate immune training is a contributory inflammatory mechanism in this murine model of atherosclerosis. METHODS: Bone marrow-derived macrophages and peritoneal macrophages were isolated from 13-week-old ApoE-/- mice, previously exposed to prenatal intra-amniotic (experimental choriomanionitis) and/or repeated postnatal (peritoneal) lipopolysaccharide (LPS). Innate immune responses were assessed by cytokine responses following ex vivo stimulation with toll-like receptor (TLR) agonists (LPS, Pam3Cys) and RPMI for 24-h. Bone marrow progenitor populations were studied using flow cytometric analysis. RESULTS: Following postnatal LPS exposure, bone marrow-derived macrophages and peritoneal macrophages produced more pro-inflammatory cytokines following TLR stimulation than those from saline-treated controls, characteristic of a trained phenotype. Cytokine production ex vivo correlated with atherosclerosis severity in vivo. Prenatal LPS did not affect cytokine production capacity. Combined prenatal and postnatal LPS exposure was associated with a reduction in populations of myeloid progenitor cells in the bone marrow. CONCLUSIONS: Postnatal inflammation results in a trained phenotype in atherosclerosis-prone mice that is not enhanced by prenatal inflammation. If analogous mechanisms occur in humans, then there may be novel early life opportunities to reduce CVD risk in infants with early life infections.


Assuntos
Aterosclerose/imunologia , Corioamnionite/imunologia , Imunidade Inata , Macrófagos Peritoneais/imunologia , Células Progenitoras Mieloides/imunologia , Peritonite/imunologia , Animais , Aterosclerose/genética , Aterosclerose/metabolismo , Células Cultivadas , Corioamnionite/induzido quimicamente , Corioamnionite/metabolismo , Citocinas/metabolismo , Modelos Animais de Doenças , Feminino , Mediadores da Inflamação/metabolismo , Lipopolissacarídeos , Macrófagos Peritoneais/metabolismo , Camundongos Knockout para ApoE , Células Progenitoras Mieloides/metabolismo , Peritonite/induzido quimicamente , Peritonite/metabolismo , Fenótipo , Gravidez
7.
Proc Natl Acad Sci U S A ; 115(21): 5576-5581, 2018 05 22.
Artigo em Inglês | MEDLINE | ID: mdl-29735704

RESUMO

Recently identified Parkinson's disease (PD) genes involved in synaptic vesicle endocytosis, such as DNAJC6 (auxilin), have further implicated synaptic dysfunction in PD pathogenesis. However, how synaptic dysfunction contributes to the vulnerability of human dopaminergic neurons has not been previously explored. Here, we demonstrate that commonly mutated, PD-linked leucine-rich repeat kinase 2 (LRRK2) mediates the phosphorylation of auxilin in its clathrin-binding domain at Ser627. Kinase activity-dependent LRRK2 phosphorylation of auxilin led to differential clathrin binding, resulting in disrupted synaptic vesicle endocytosis and decreased synaptic vesicle density in LRRK2 patient-derived dopaminergic neurons. Moreover, impaired synaptic vesicle endocytosis contributed to the accumulation of oxidized dopamine that in turn mediated pathogenic effects such as decreased glucocerebrosidase activity and increased α-synuclein in mutant LRRK2 neurons. Importantly, these pathogenic phenotypes were partially attenuated by restoring auxilin function in mutant LRRK2 dopaminergic neurons. Together, this work suggests that mutant LRRK2 disrupts synaptic vesicle endocytosis, leading to altered dopamine metabolism and dopamine-mediated toxic effects in patient-derived dopaminergic neurons.


Assuntos
Auxilinas/metabolismo , Dopamina/farmacologia , Neurônios Dopaminérgicos/patologia , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/metabolismo , Mutação , Doença de Parkinson/patologia , Vesículas Sinápticas/patologia , Auxilinas/genética , Células Cultivadas , Dopaminérgicos/farmacologia , Neurônios Dopaminérgicos/metabolismo , Endocitose/efeitos dos fármacos , Humanos , Serina-Treonina Proteína Quinase-2 com Repetições Ricas em Leucina/genética , Doença de Parkinson/genética , Doença de Parkinson/metabolismo , Fosforilação , Vesículas Sinápticas/metabolismo
8.
J Cell Biochem ; 120(5): 7412-7427, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30426531

RESUMO

Cripto-1 has been implicated in a number of human cancers. Although there is high potential for a role of Cripto-1 in glioblastoma multiforme (GBM) pathogenesis and progression, few studies have tried to define its role in GBM. These studies were limited in that Cripto-1 expression was not studied in detail in relation to markers of cancer initiation and progression. Therefore, these correlative studies allowed limited interpretation of Criptos-1's effect on the various aspects of GBM development using the U87 GBM cell line. In this study, we sought to delineate the role of Cripto-1 in facilitating pathogenesis, stemness, proliferation, invasion, migration and angiogenesis in GBM. Our findings show that upon overexpressing Cripto-1 in U87 GBM cells, the stemness markers Nanog, Oct4, Sox2, and CD44 increased expression. Similarly, an increase in Ki67 was observed demonstrating Cripto-1's potential to induce cellular proliferation. Likewise, we report a novel finding that increased expression of the markers of migration and invasion, Vimentin and Twist, correlated with upregulation of Cripto-1. Moreover, Cripto-1 exposure led to VEGFR-2 overexpression along with higher tube formation under conditions promoting endothelial growth. Taken together our results support a role for Cripto-1 in the initiation, development, progression, and maintenance of GBM pathogenesis. The data presented here are also consistent with a role for Cripto-1 in the re-growth and invasive growth in GBM. This highlights its potential use as a predictive and diagnostic marker in GBM as well as a therapeutic target.

9.
Clin Sci (Lond) ; 133(10): 1185-1196, 2019 05 31.
Artigo em Inglês | MEDLINE | ID: mdl-31088858

RESUMO

Atherosclerosis is a chronic inflammatory disease that has its origins in early life. Postnatal inflammation exacerbates atherosclerosis, but the possible effect of intrauterine inflammation is largely unexplored. Exposure to inflammation in utero is common, especially in infants born preterm, who have increased cardiovascular risk in adulthood. We hypothesised that exposure to inflammation before birth would accelerate the development of atherosclerosis, with the most severe atherosclerosis following exposure to both pre- and postnatal inflammation. Here we studied the effect of prenatal and postnatal inflammation on the development of atherosclerosis by combining established techniques for modelling histological chorioamnionitis and atherosclerosis using apolipoprotein E (ApoE) knockout mice. A single intra-amniotic (IA) injection of lipopolysaccharide (LPS) caused intrauterine inflammation, and increased atherosclerosis at 13 weeks of postnatal age. In mice exposed to postnatal LPS, chorioamnionitis modulated subsequent responses; atherosclerotic lesion size, number and severity were greatest for mice exposed to both intrauterine and postnatal inflammation, with a concomitant decrease in collagen content and increased inflammation of the atherosclerotic plaque. In conclusion, pre- and postnatal inflammation have additive and deleterious effects on the development of atherosclerosis in ApoE knockout mice. The findings are particularly relevant to preterm human infants, whose gestations are frequently complicated by chorioamnionitis and who are particularly susceptible to repeated postnatal infections. Human and mechanistic studies are warranted to guide preventative strategies.


Assuntos
Aterosclerose/etiologia , Corioamnionite , Inflamação/complicações , Efeitos Tardios da Exposição Pré-Natal , Animais , Feminino , Masculino , Camundongos Knockout para ApoE , Gravidez
10.
Am J Hum Genet ; 95(6): 721-8, 2014 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-25480035

RESUMO

Dendritic spines represent the major site of neuronal activity in the brain; they serve as the receiving point for neurotransmitters and undergo rapid activity-dependent morphological changes that correlate with learning and memory. Using a combination of homozygosity mapping and next-generation sequencing in two consanguineous families affected by nonsyndromic autosomal-recessive intellectual disability, we identified truncating mutations in formin 2 (FMN2), encoding a protein that belongs to the formin family of actin cytoskeleton nucleation factors and is highly expressed in the maturing brain. We found that FMN2 localizes to punctae along dendrites and that germline inactivation of mouse Fmn2 resulted in animals with decreased spine density; such mice were previously demonstrated to have a conditioned fear-learning defect. Furthermore, patient neural cells derived from induced pluripotent stem cells showed correlated decreased synaptic density. Thus, FMN2 mutations link intellectual disability either directly or indirectly to the regulation of actin-mediated synaptic spine density.


Assuntos
Transtornos Cromossômicos/genética , Deficiência Intelectual/genética , Proteínas dos Microfilamentos/genética , Proteínas Nucleares/genética , Deleção de Sequência , Adolescente , Adulto , Sequência de Bases , Transtornos Cromossômicos/fisiopatologia , Estudos de Coortes , Consanguinidade , Egito , Exoma/genética , Feminino , Forminas , Genes Recessivos , Ligação Genética , Sequenciamento de Nucleotídeos em Larga Escala , Homozigoto , Humanos , Deficiência Intelectual/fisiopatologia , Masculino , Proteínas dos Microfilamentos/metabolismo , Dados de Sequência Molecular , Proteínas Nucleares/metabolismo , Paquistão , Linhagem , Análise de Sequência de DNA
11.
Clin Sci (Lond) ; 129(8): 769-84, 2015 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-26223841

RESUMO

Cardiovascular disease continues to be the leading cause of global morbidity and mortality. Traditional risk factors account for only part of the attributable risk. The origins of atherosclerosis are in early life, a potential albeit largely unrecognized window of opportunity for early detection and treatment of subclinical cardiovascular disease. There are robust epidemiological data indicating that poor intrauterine growth and/or prematurity, and perinatal factors such as maternal hypercholesterolaemia, smoking, diabetes and obesity, are associated with adverse cardiovascular intermediate phenotypes in childhood and adulthood. Many of these early-life risk factors result in a heightened inflammatory state. Inflammation is a central mechanism in the development of atherosclerosis and cardiovascular disease, but few studies have investigated the role of overt perinatal infection and inflammation (chorioamnionitis) as a potential contributor to cardiovascular risk. Limited evidence from human and experimental models suggests an association between chorioamnionitis and cardiac and vascular dysfunction. Early life inflammatory events may be an important mechanism in the early development of cardiovascular risk and may provide insights into the associations between perinatal factors and adult cardiovascular disease. This review aims to summarise current data on the early life origins of atherosclerosis and cardiovascular disease, with particular focus on perinatal inflammation.


Assuntos
Aterosclerose/etiologia , Corioamnionite , Doenças do Recém-Nascido , Inflamação/complicações , Animais , Feminino , Humanos , Recém-Nascido , Gravidez
12.
Apoptosis ; 18(3): 286-99, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23299931

RESUMO

α-Tocopheryl succinate (α-TOS) is a promising anti-cancer agent due to its selectivity for cancer cells. It is important to understand whether long-term exposure of tumour cells to the agent will render them resistant to the treatment. Exposure of the non-small cell lung carcinoma H1299 cells to escalating doses of α-TOS made them resistant to the agent due to the upregulation of the ABCA1 protein, which caused its efflux. Full susceptibility of the cells to α-TOS was restored by knocking down the ABCA1 protein. Similar resistance including ABCA1 gene upregulation was observed in the A549 lung cancer cells exposed to α-TOS. The resistance of the cells to α-TOS was overcome by its mitochondrially targeted analogue, MitoVES, that is taken up on the basis of the membrane potential, bypassing the enhanced expression of the ABCA1 protein. The in vitro results were replicated in mouse models of tumours derived from parental and resistant H1299 cells. We conclude that long-term exposure of cancer cells to α-TOS causes their resistance to the drug, which can be overcome by its mitochondrially targeted counterpart. This finding should be taken into consideration when planning clinical trials with vitamin E analogues.


Assuntos
Transportadores de Cassetes de Ligação de ATP/fisiologia , Carcinoma Pulmonar de Células não Pequenas/tratamento farmacológico , Resistencia a Medicamentos Antineoplásicos , Neoplasias Pulmonares/tratamento farmacológico , Mitocôndrias/efeitos dos fármacos , alfa-Tocoferol/uso terapêutico , Transportador 1 de Cassete de Ligação de ATP , Transportadores de Cassetes de Ligação de ATP/genética , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Técnicas de Silenciamento de Genes , Camundongos
13.
Nat Biotechnol ; 41(1): 140-149, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36217029

RESUMO

Understanding the mechanisms of coronavirus disease 2019 (COVID-19) disease severity to efficiently design therapies for emerging virus variants remains an urgent challenge of the ongoing pandemic. Infection and immune reactions are mediated by direct contacts between viral molecules and the host proteome, and the vast majority of these virus-host contacts (the 'contactome') have not been identified. Here, we present a systematic contactome map of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) with the human host encompassing more than 200 binary virus-host and intraviral protein-protein interactions. We find that host proteins genetically associated with comorbidities of severe illness and long COVID are enriched in SARS-CoV-2 targeted network communities. Evaluating contactome-derived hypotheses, we demonstrate that viral NSP14 activates nuclear factor κB (NF-κB)-dependent transcription, even in the presence of cytokine signaling. Moreover, for several tested host proteins, genetic knock-down substantially reduces viral replication. Additionally, we show for USP25 that this effect is phenocopied by the small-molecule inhibitor AZ1. Our results connect viral proteins to human genetic architecture for COVID-19 severity and offer potential therapeutic targets.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , SARS-CoV-2/genética , COVID-19/genética , Proteoma/genética , Síndrome de COVID-19 Pós-Aguda , Replicação Viral/genética , Ubiquitina Tiolesterase/farmacologia
14.
Bioorg Med Chem Lett ; 22(10): 3392-7, 2012 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-22542194

RESUMO

A series of 2-(1H-pyrazol-1-yl)pyridines are described as inhibitors of ALK5 (TGFß receptor I kinase). Modeling compounds in the ALK5 kinase domain enabled some optimization of potency via substitutions on the pyrazole core. One of these compounds PF-03671148 gave a dose dependent reduction in TGFß induced fibrotic gene expression in human fibroblasts. A similar reduction in fibrotic gene expression was observed when PF-03671148 was applied topically in a rat wound repair model. Thus these compounds have potential utility for the prevention of dermal scarring.


Assuntos
Cicatriz/prevenção & controle , Descoberta de Drogas , Inibidores de Proteínas Quinases/química , Inibidores de Proteínas Quinases/farmacologia , Proteínas Serina-Treonina Quinases/antagonistas & inibidores , Piridinas/química , Piridinas/farmacologia , Receptores de Fatores de Crescimento Transformadores beta/antagonistas & inibidores , Pele/efeitos dos fármacos , Animais , Modelos Moleculares , Fosforilação , Ratos , Receptor do Fator de Crescimento Transformador beta Tipo I
15.
Elife ; 102021 07 07.
Artigo em Inglês | MEDLINE | ID: mdl-34232860

RESUMO

Mobile genetic elements, elements that can move horizontally between genomes, have profound effects on their host's fitness. The phage-inducible chromosomal island-like element (PLE) is a mobile element that integrates into the chromosome of Vibrio cholerae and parasitizes the bacteriophage ICP1 to move between cells. This parasitism by PLE is such that it abolishes the production of ICP1 progeny and provides a defensive boon to the host cell population. In response to the severe parasitism imposed by PLE, ICP1 has acquired an adaptive CRISPR-Cas system that targets the PLE genome during infection. However, ICP1 isolates that naturally lack CRISPR-Cas are still able to overcome certain PLE variants, and the mechanism of this immunity against PLE has thus far remained unknown. Here, we show that ICP1 isolates that lack CRISPR-Cas encode an endonuclease in the same locus, and that the endonuclease provides ICP1 with immunity to a subset of PLEs. Further analysis shows that this endonuclease is of chimeric origin, incorporating a DNA-binding domain that is highly similar to some PLE replication origin-binding proteins. This similarity allows the endonuclease to bind and cleave PLE origins of replication. The endonuclease appears to exert considerable selective pressure on PLEs and may drive PLE replication module swapping and origin restructuring as mechanisms of escape. This work demonstrates that new genome defense systems can arise through domain shuffling and provides a greater understanding of the evolutionary forces driving genome modularity and temporal succession in mobile elements.


Assuntos
Proteínas de Bactérias/genética , Bacteriófagos/fisiologia , Endonucleases/genética , Vibrio cholerae/genética , Proteínas de Bactérias/metabolismo , Sistemas CRISPR-Cas , Endonucleases/metabolismo , Vibrio cholerae/virologia
16.
mBio ; 13(1): e0308821, 2021 02 22.
Artigo em Inglês | MEDLINE | ID: mdl-35164562

RESUMO

Vibrio cholerae is a significant threat to global public health in part due to its propensity for large-scale evolutionary sweeps where lineages emerge and are replaced. These sweeps may originate from the Bay of Bengal, where bacteriophage predation and the evolution of antiphage counterdefenses is a recurring theme. The bacteriophage ICP1 is a key predator of epidemic V. cholerae and is notable for acquiring a CRISPR-Cas system to combat PLE, a defensive subviral parasite encoded by its V. cholerae host. Here, we describe the discovery of four previously unknown PLE variants through a retrospective analysis of >3,000 publicly available sequences as well as one additional variant (PLE10) from recent surveillance of cholera patients in Bangladesh. In recent sampling we also observed a lineage sweep of PLE-negative V. cholerae occurring within the patient population in under a year. This shift coincided with a loss of ICP1's CRISPR-Cas system in favor of a previously prevalent PLE-targeting endonuclease called Odn. Interestingly, PLE10 was resistant to ICP1-encoded Odn, yet it was not found in any recent V. cholerae strains. We also identified isolates from within individual patient samples that revealed both mixed PLE(+)/PLE(-) V. cholerae populations and ICP1 strains possessing CRISPR-Cas or Odn with evidence of in situ recombination. These findings reinforce our understanding of the successive nature of V. cholerae evolution and suggest that ongoing surveillance of V. cholerae, ICP1, and PLE in Bangladesh is important for tracking genetic developments relevant to pandemic cholera that can occur over relatively short timescales. IMPORTANCE With 1 to 4 million estimated cases annually, cholera is a disease of serious global concern in regions where access to safe drinking water is limited by inadequate infrastructure, inequity, or natural disaster. The Global Task Force on Cholera Control (GTFCC.org) considers outbreak surveillance to be a primary pillar in the strategy to reduce mortality from cholera worldwide. Therefore, developing a better understanding of temporal evolutionary changes in the causative agent of cholera, Vibrio cholerae, could help in those efforts. The significance of our research is in tracking the genomic shifts that distinguish V. cholerae outbreaks, with specific attention paid to current and historical trends in the arms race between V. cholerae and a cooccurring viral (bacteriophage) predator. Here, we discover additional diversity of a specific phage defense system in epidemic V. cholerae and document the loss of a phage-encoded CRISPR-Cas system, underscoring the dynamic nature of microbial populations across cholera outbreaks.


Assuntos
Bacteriófagos , Cólera , Parasitos , Vibrio cholerae , Animais , Humanos , Cólera/epidemiologia , Sistemas CRISPR-Cas , Bacteriófagos/genética , Estudos Retrospectivos , Vibrio cholerae/genética
17.
J Emerg Trauma Shock ; 14(1): 42-47, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33911436

RESUMO

BACKGROUND: Patients with an alcohol use disorder (AUD) have an increased risk of developing complications during their hospital stays; however, how AUD impacts the length of stay (LOS) and the utilization of hospital resources remains inconclusive. AIM: This study aimed to identify the associations between AUD, defined by self-reported alcohol consumption, blood alcohol content (BAC), and hospital LOS (HLOS) including intensive care unit (ICU) LOS in the trauma patient population. STUDY DESIGN: We conducted a retrospective study analyzing data obtained from 2010 to 2018 at a university-based, level-one trauma emergency department. We identified 1689 adult trauma patients who completed the AUDs identification test (AUDIT) and were admitted to the hospital. We retrieved BAC, age, gender, LOS, and injury severity score (ISS) from the patient charts. The independent samples' median test was used to assess the association of HLOS and ICULOS with ISS, BAC levels, or AUDIT scores. RESULTS: ISS was directly associated with higher HLOS (P < 0.001) and ICULOS (P < 0.001); however there was no statistically significant association between AUDIT scores and ICULOS (P = 0.21) or HLOS (P = 0.86). There was also no statistically significant association between BAC and HLOS (P = 0.09) or ICULOS (P = 0.07). CONCLUSIONS: Our study found no associations between AUDIT, BAC, and both hospital and ICU LOS in trauma patients even though the literature supported an increased risk of medical complications in the AUD patients.

18.
Cell Syst ; 10(1): 25-38.e10, 2020 01 22.
Artigo em Inglês | MEDLINE | ID: mdl-31668799

RESUMO

Many traits are complex, depending non-additively on variant combinations. Even in model systems, such as the yeast S. cerevisiae, carrying out the high-order variant-combination testing needed to dissect complex traits remains a daunting challenge. Here, we describe "X-gene" genetic analysis (XGA), a strategy for engineering and profiling highly combinatorial gene perturbations. We demonstrate XGA on yeast ABC transporters by engineering 5,353 strains, each deleted for a random subset of 16 transporters, and profiling each strain's resistance to 16 compounds. XGA yielded 85,648 genotype-to-resistance observations, revealing high-order genetic interactions for 13 of the 16 transporters studied. Neural networks yielded intuitive functional models and guided exploration of fluconazole resistance, which was influenced non-additively by five genes. Together, our results showed that highly combinatorial genetic perturbation can functionally dissect complex traits, supporting pursuit of analogous strategies in human cells and other model systems.


Assuntos
Transporte Biológico/genética , Proteínas de Membrana Transportadoras/genética , Humanos
19.
Bioorg Med Chem Lett ; 19(8): 2176-8, 2009 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-19286380

RESUMO

A series of diphenyl ethers was prepared and evaluated for androgen receptor antagonist activity in human androgen receptor binding and cellular functional assays. Analogs with potent in vitro activities were evaluated for topical in vivo efficacy in the Golden Syrian Hamster ear model. Several compounds showed reduction in wax esters in this validated animal model.


Assuntos
Antagonistas de Androgênios/administração & dosagem , Antagonistas de Androgênios/química , Antagonistas de Receptores de Andrógenos , Éteres Fenílicos/administração & dosagem , Éteres Fenílicos/síntese química , Sebo/efeitos dos fármacos , Sebo/metabolismo , Administração Tópica , Animais , Linhagem Celular Tumoral , Cricetinae , Humanos , Masculino , Mesocricetus , Receptores Androgênicos/química , Reprodutibilidade dos Testes
20.
Neurotherapeutics ; 16(3): 611-634, 2019 07.
Artigo em Inglês | MEDLINE | ID: mdl-31183763

RESUMO

Lysosomes are acidic, membrane-bound organelles that serve as the primary catabolic compartment of the cell. They are crucial to a variety of cellular processes from nutrient storage to autophagy. Given the diversity of lysosomal functions, it is unsurprising that lysosomes are also emerging as important players in aging. Lysosomal dysfunction is implicated in several aging-related neurodegenerative diseases including Alzheimer's, Parkinson's, amyotrophic lateral sclerosis/frontotemporal dementia, and Huntington's. Although the precise role of lysosomes in the aging brain is not well-elucidated, some insight into their function has been gained from our understanding of the pathophysiology of age-dependent neurodegenerative diseases. Therapeutic strategies targeting lysosomes and autophagic machinery have already been tested in several of these diseases with promising results, suggesting that improving lysosomal function could be similarly beneficial in preserving function in the aging brain.


Assuntos
Envelhecimento/metabolismo , Encéfalo/metabolismo , Lisossomos/fisiologia , Doenças Neurodegenerativas/metabolismo , Envelhecimento/fisiologia , Esclerose Lateral Amiotrófica/metabolismo , Encéfalo/fisiologia , Demência Frontotemporal/metabolismo , Humanos , Doença de Huntington/metabolismo , Mitocôndrias/metabolismo , Doenças Neurodegenerativas/prevenção & controle , Doença de Parkinson/metabolismo
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