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1.
Sci Total Environ ; 876: 162781, 2023 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-36906011

RESUMO

Arbuscular mycorrhizal fungi were recovered from soil samples from the naturally radioactive soil at the long-abandoned South Terras uranium mine in Cornwall, UK. Species of Rhizophagus, Claroideoglomus, Paraglomus, Septoglomus, and Ambispora were recovered, and pot cultures from all except Ambispora were established. Cultures were identified to species level using morphological observation and rRNA gene sequencing combined with phylogenetic analysis. These cultures were used in pot experiments designed with a compartmentalised system to assess the contribution of fungal hyphae to the accumulation of essential elements, such as copper and zinc, and non-essential elements, such as lead, arsenic, thorium, and uranium into root and shoot tissues of Plantago lanceolata. The results indicated that none of the treatments had any positive or negative impact on shoot and root biomass. However, Rhizophagus irregularis treatments showed higher accumulation of copper and zinc in shoots, while R. irregularis and Septoglomus constrictum enhanced arsenic accumulation in roots. Moreover, R. irregularis increased uranium concentration in roots and shoots of the P. lanceolata plant. This study provides useful insight into fungal-plant interactions that determine metal and radionuclide transfer from soil into the biosphere at contaminated sites such as mine workings.

2.
Biomed Pharmacother ; 160: 114305, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36731340

RESUMO

Selinexor (KPT-330), a small-molecule inhibitor of exportin-1 (XPO1, CRM1) with potent anticancer activity, has recently been granted FDA approval for treatment of relapsed/refractory multiple myeloma and diffuse large B-cell lymphoma (DLBCL), with a number of additional indications currently under clinical investigation. Since selinexor has often demonstrated synergy when used in combination with other drugs, notably bortezomib and dexamethasone, a more comprehensive approach to uncover new beneficial interactions would be of great value. Moreover, stratifying patients, personalizing therapeutics and improving clinical outcomes requires a better understanding of the genetic vulnerabilities and resistance mechanisms underlying drug response. Here, we used CRISPR-Cas9 loss-of-function chemogenetic screening to identify drug-gene interactions with selinexor in chronic myeloid leukemia, multiple myeloma and DLBCL cell lines. We identified the TGFß-SMAD4 pathway as an important mediator of resistance to selinexor in multiple myeloma cells. Moreover, higher activity of this pathway correlated with prolonged progression-free survival in multiple myeloma patients treated with selinexor, indicating that the TGFß-SMAD4 pathway is a potential biomarker predictive of therapeutic outcome. In addition, we identified ASB8 (ankyrin repeat and SOCS box containing 8) as a shared modulator of selinexor sensitivity across all tested cancer types, with both ASB8 knockout and overexpression resulting in selinexor hypersensitivity. Mechanistically, we showed that ASB8 promotes selinexor-induced proteasomal degradation of XPO1. This study provides insight into the genetic factors that influence response to selinexor treatment and could support both the development of predictive biomarkers as well as new drug combinations.


Assuntos
Linfoma Difuso de Grandes Células B , Mieloma Múltiplo , Humanos , Mieloma Múltiplo/tratamento farmacológico , Mieloma Múltiplo/genética , Transporte Ativo do Núcleo Celular , Carioferinas/genética , Carioferinas/metabolismo , Hidrazinas/farmacologia , Hidrazinas/uso terapêutico , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Proteínas Supressoras da Sinalização de Citocina
3.
Space Sci Rev ; 219(1): 9, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36747508

RESUMO

The Orbiting Astronomical Satellite for Investigating Stellar Systems (OASIS), a proposed Astrophysics MIDEX-class mission concept, has an innovative 14-meter diameter inflatable primary mirror that will provide the sensitivity to study far-infrared continuum and line emission from galaxies at all redshifts with high spectral resolution heterodyne receivers. OASIS will have the sensitivity to follow the water trail from galaxies to the comets that create oceans. It will bring an understanding of the role of water in galaxy evolution and its part of the oxygen budget, by measuring water emission from local to intermediate redshift galaxies, observations that have not been possible from the ground. Observation of the ground-state HD line will accurately measure gas mass in a wide variety of astrophysical objects. Thanks to its exquisite spatial resolution and sensitivity, OASIS will, during its one-year baseline mission, detect water in galaxies with unprecedented statistical significance. This paper reviews the extragalactic science achievable and planned with OASIS.

4.
Blood Adv ; 2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36827679

RESUMO

Selinexor (KPT-330) is a small molecule inhibitor of XPO1 (exportin 1, Chromosome Region Maintenance 1/CRM1), which mediates the transport of tumor suppressor proteins, oncogene mRNAs and other proteins involved in governing cell growth, from the cell nucleus to the cytoplasm. It is often overexpressed in many cancer types. Since eukaryotic translation initiator factor 4E (eIF4E) plays a critical role in cancer protein translation in multiple myeloma (MM), we evaluated the effectiveness of combined inhibition of protein translation and with a nuclear export inhibitor in MM. Selinexor, an nuclear protein inhibitor of nuclear protein export, dose-dependently decreased eIF4E, IKZF1 and c-MYC protein levelsinhibits eIF4E-directed translation of oncoproteins such as IKZF1 and c-MYC.. Using a doxycycline- inducible pLKO-Tet-On vector, knockdown of eIF4E significantly enhanced the antiproliferative effects of selinexor, sensitized resistant MM cells to selinexor, and increased apoptosis in MM cells. Immunofluorescent analysis of MM cells showed that the combined treatment increased localization of residual eIF4E to the nucleus compared with selinexor treatment alone. In vivo studies showed that eIF4E knockdown enhanced the anti-tumor activity of selinexor in mice. Overexpression of eIF4E at least partially rescued the effects of selinexor in MM cells by reducing G1 cell cycle arrest as well as increasing the selinexor-IC50 10-fold. Moreover, the combination of selinexor with pharmacologic inhibitors of protein translation showed synergistic anti-MM effects. These results suggest a synergistic anti-MM effects of selinexor combined with eIF4E inhibitors in vitro. Our work provides a better understanding of the potential mechanism of resistance to selinexor and a rationale for combining selinexor with eIF4E inhibitors for the treatment of MM.

7.
ACS Pharmacol Transl Sci ; 6(1): 52-64, 2023 Jan 13.
Artigo em Inglês | MEDLINE | ID: mdl-36654758

RESUMO

The related peptides pituitary adenylate cyclase-activating polypeptide (PACAP) and vasoactive intestinal peptide (VIP) have diverse biological functions in peripheral tissues and the central nervous system. Therefore, these peptides and their three receptors represent potential drug targets for several conditions, including neurological and pain-related disorders. However, very little is known about how these peptides regulate their receptors through processes such as internalization. Therefore, we developed tools to study receptor regulation through the synthesis of fluorescently labeled analogues of PACAP-38, PACAP-27, and VIP using copper-mediated 1,3-dipolar cycloaddition of the Cy5 fluorophore. The functionality of Cy5-labeled peptides at their receptors was confirmed in cAMP accumulation assays. Internalization of the Cy5-labeled peptides was then examined and quantified at two distinct PAC1 receptor splice variants, VPAC1 and VPAC2 receptors in transfected cells. All labeled peptides were functional, exhibiting comparable cAMP pharmacology to their unlabeled counterparts and underwent internalization in a time-dependent manner. Temporal differences in the internalization profiles were observed between Cy5-labeled peptides at the PAC1n, PAC1s, VPAC1, and VPAC2 receptors. Interestingly, the pattern of Cy5-labeled peptide activity differed for cAMP accumulation and internalization, indicating that these peptides differentially stimulate cAMP accumulation and internalization and therefore display biased agonism. This novel insight into PACAP-responsive receptor signaling and internalization may provide a unique avenue for future therapeutic development. The fluorescently labeled PACAP and VIP peptides described herein, which we validated as tools to study receptor internalization, will have utility across a broad range of applications and provide greater insight into this receptor family.

8.
Nat Cancer ; 4(1): 27-42, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36581735

RESUMO

Acute myeloid leukemia (AML) is a hematopoietic malignancy with poor prognosis and limited treatment options. Here we provide a comprehensive census of the bone marrow immune microenvironment in adult and pediatric patients with AML. We characterize unique inflammation signatures in a subset of AML patients, associated with inferior outcomes. We identify atypical B cells, a dysfunctional B-cell subtype enriched in patients with high-inflammation AML, as well as an increase in CD8+GZMK+ and regulatory T cells, accompanied by a reduction in T-cell clonal expansion. We derive an inflammation-associated gene score (iScore) that associates with poor survival outcomes in patients with AML. Addition of the iScore refines current risk stratifications for patients with AML and may enable identification of patients in need of more aggressive treatment. This work provides a framework for classifying patients with AML based on their immune microenvironment and a rationale for consideration of the inflammatory state in clinical settings.


Assuntos
Leucemia Mieloide Aguda , Adulto , Humanos , Criança , Leucemia Mieloide Aguda/genética , Medula Óssea/patologia , Linfócitos T Reguladores/patologia , Inflamação/patologia , Medição de Risco , Microambiente Tumoral
9.
Magn Reson Med ; 2022 Dec 05.
Artigo em Inglês | MEDLINE | ID: mdl-36468638

RESUMO

PURPOSE: Model-constrained reconstruction with Fourier-based undersampling (MoReFUn) is introduced to accelerate the acquisition of dynamic MRI using hyperpolarized [1-13 C]-pyruvate. METHODS: The MoReFUn method resolves spatial aliasing using constraints introduced by a pharmacokinetic model that describes the signal evolution of both pyruvate and lactate. Acceleration was evaluated on three single-channel data sets: a numerical digital phantom that is used to validate the accuracy of reconstruction and model parameter restoration under various SNR and undersampling ratios, prospectively and retrospectively sampled data of an in vitro dynamic multispectral phantom, and retrospectively undersampled imaging data from a prostate cancer patient to test the fidelity of reconstructed metabolite time series. RESULTS: All three data sets showed successful reconstruction using MoReFUn. In simulation and retrospective phantom data, the restored time series of pyruvate and lactate maintained the image details, and the mean square residual error of the accelerated reconstruction increased only slightly (< 10%) at a reduction factor up to 8. In prostate data, the quantitative estimation of the conversion-rate constant of pyruvate to lactate was achieved with high accuracy of less than 10% error at a reduction factor of 2 compared with the conversion rate derived from unaccelerated data. CONCLUSION: The MoReFUn technique can be used as an effective and reliable imaging acceleration method for metabolic imaging using hyperpolarized [1-13 C]-pyruvate.

10.
Chest ; 2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36470416

RESUMO

BACKGROUND: Rheumatoid arthritis (RA) associated interstitial lung disease (ILD) is common in patients with RA and leads to significant morbidity and mortality. There are no randomized, placebo-controlled data to support the role of immunosuppression to treat RA-ILD despite being widely used in clinical practice. RESEARCH QUESTION: How does immunosuppression impact pulmonary function trajectory in a multi-site retrospective cohort of RA-ILD patients? STUDY DESIGN AND METHODS: Patients with RA who started treatment for ILD with mycophenolate, azathioprine, or rituximab were retrospectively identified from five ILD centers. Change in lung function before and after treatment was analyzed using a linear spline mixed effect model with random intercept. Prespecified secondary analyses examined the impact of radiologic pattern of ILD (i.e., usual interstitial pneumonia [UIP] vs non-UIP) on treatment trajectory. RESULTS: 212 patients were included in the analysis: 92 (43.4%) were treated with azathioprine, 77 (36.3%) with mycophenolate mofetil and 43 (20.3%) with rituximab. In the combined analysis of all three agents, there was an improvement in forced vital capacity (FVC) % predicted after 12 months of treatment compared to the potential 12-month response without treatment [+3.90%, p=< 0.001; 95% CI, (1.95, 5.84)]. Diffusing capacity for carbon monoxide (DLCO) % predicted also improved at 12 months [+4.53%, p=<0.001; (2.12, 6.94)]. Neither the UIP pattern of ILD or choice of immunosuppressive agent significantly impacted the pulmonary function trajectory on immunosuppression. INTERPRETATION: Immunosuppression was associated with an improved trajectory in FVC and DLCO compared to the pre-treatment pulmonary function trajectory. Prospective, randomized trials are required to validate these findings.

11.
Int J Mol Sci ; 23(24)2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36555690

RESUMO

Calcitonin gene-related peptide (CGRP) is a key component of migraine pathophysiology, yielding effective migraine therapeutics. CGRP receptors contain a core accessory protein subunit: receptor activity-modifying protein 1 (RAMP1). Understanding of RAMP1 expression is incomplete, partly due to the challenges in identifying specific and validated antibody tools. We profiled antibodies for immunodetection of RAMP1 using Western blotting, immunocytochemistry and immunohistochemistry, including using RAMP1 knockout mouse tissue. Most antibodies could detect RAMP1 in Western blotting and immunocytochemistry using transfected cells. Two antibodies (844, ab256575) could detect a RAMP1-like band in Western blots of rodent brain but not RAMP1 knockout mice. However, cross-reactivity with other proteins was evident for all antibodies. This cross-reactivity prevented clear conclusions about RAMP1 anatomical localization, as each antibody detected a distinct pattern of immunoreactivity in rodent brain. We cannot confidently attribute immunoreactivity produced by RAMP1 antibodies (including 844) to the presence of RAMP1 protein in immunohistochemical applications in brain tissue. RAMP1 expression in brain and other tissues therefore needs to be revisited using RAMP1 antibodies that have been comprehensively validated using multiple strategies to establish multiple lines of convincing evidence. As RAMP1 is important for other GPCR/ligand pairings, our results have broader significance beyond the CGRP field.


Assuntos
Peptídeo Relacionado com Gene de Calcitonina , Transtornos de Enxaqueca , Camundongos , Animais , Proteína 1 Modificadora da Atividade de Receptores/metabolismo , Peptídeo Relacionado com Gene de Calcitonina/metabolismo , Receptores de Peptídeo Relacionado com o Gene de Calcitonina/metabolismo , Imuno-Histoquímica , Transtornos de Enxaqueca/metabolismo
12.
Schizophrenia (Heidelb) ; 8(1): 114, 2022 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-36566277

RESUMO

People with schizophrenia exhibit reduced alpha oscillations and frontotemporal coordination of brain activity. Alpha oscillations are associated with top-down inhibition. Reduced alpha oscillations may fail to censor spurious endogenous activity, leading to auditory hallucinations. Transcranial alternating current stimulation (tACS) at the alpha frequency was shown to enhance alpha oscillations in people with schizophrenia and may thus be a network-based treatment for auditory hallucinations. We conducted a double-blind, randomized, placebo-controlled pilot clinical trial to examine the efficacy of 10-Hz tACS in treating auditory hallucinations in people with schizophrenia. 10-Hz tACS was administered in phase at the dorsolateral prefrontal cortex and the temporoparietal junction with a return current at Cz. Patients were randomized to receive tACS or sham for five consecutive days during the treatment week (40 min/day), followed by a maintenance period, during which participants received weekly tACS (40 min/visit) or sham. tACS treatment reduced general psychopathology (p < 0.05, Cohen's d = -0.690), especially depression (p < 0.005, Cohen's d = -0.806), but not auditory hallucinations. tACS treatment increased alpha power in the target region (p < 0.05), increased the frequency of peak global functional connectivity towards 10 Hz (p < 0.05), and reduced left-right frontal functional connectivity (p < 0.005). Importantly, changes in brain functional connectivity significantly correlated with symptom improvement (p < 0.05). Daily 10 Hz-tACS increased alpha power and altered alpha-band functional connectivity. Successful target engagement reduced depression and other general psychopathology symptoms, but not auditory hallucinations. Considering existing research of 10Hz tACS as a treatment for major depressive disorder, our study demonstrates its transdiagnostic potential for treating depression.

13.
Nat Neurosci ; 25(12): 1714-1723, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36424430

RESUMO

Aging is accompanied by a host of social and biological changes that correlate with behavior, cognitive health and susceptibility to neurodegenerative disease. To understand trajectories of brain aging in a primate, we generated a multiregion bulk (N = 527 samples) and single-nucleus (N = 24 samples) brain transcriptional dataset encompassing 15 brain regions and both sexes in a unique population of free-ranging, behaviorally phenotyped rhesus macaques. We demonstrate that age-related changes in the level and variance of gene expression occur in genes associated with neural functions and neurological diseases, including Alzheimer's disease. Further, we show that higher social status in females is associated with younger relative transcriptional ages, providing a link between the social environment and aging in the brain. Our findings lend insight into biological mechanisms underlying brain aging in a nonhuman primate model of human behavior, cognition and health.


Assuntos
Doenças Neurodegenerativas , Feminino , Masculino , Humanos , Animais , Macaca mulatta , Transcriptoma , Envelhecimento/genética , Meio Social , Núcleo Solitário
14.
Int J Mol Sci ; 23(22)2022 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-36430275

RESUMO

Pituitary adenylate cyclase-activating peptide (PACAP) is a neuropeptide expressed in the trigeminal ganglia (TG). The TG conducts nociceptive signals in the head and may play roles in migraine. PACAP infusion provokes headaches in healthy individuals and migraine-like attacks in patients; however, it is not clear whether targeting this system could be therapeutically efficacious. To effectively target the PACAP system, an understanding of PACAP receptor distribution is required. Therefore, this study aimed to characterize commercially available antibodies and use these to detect PACAP-responsive receptors in the TG. Antibodies were initially validated in receptor transfected cell models and then used to explore receptor expression in rat and human TG. Antibodies were identified that could detect PACAP-responsive receptors, including the first antibody to differentiate between the PAC1n and PAC1s receptor splice variants. PAC1, VPAC1, and VPAC2 receptor-like immunoreactivity were observed in subpopulations of both neuronal and glial-like cells in the TG. In this study, PAC1, VPAC1, and VPAC2 receptors were detected in the TG, suggesting they are all potential targets to treat migraine. These antibodies may be useful tools to help elucidate PACAP-responsive receptor expression in tissues. However, most antibodies exhibited limitations, requiring the use of multiple methodologies and the careful inclusion of controls.


Assuntos
Transtornos de Enxaqueca , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase , Humanos , Ratos , Animais , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/genética , Receptores de Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Polipeptídeo Hipofisário Ativador de Adenilato Ciclase/metabolismo , Gânglio Trigeminal/metabolismo , Expressão Gênica , Anticorpos , Transtornos de Enxaqueca/genética
15.
Artigo em Inglês | MEDLINE | ID: mdl-36399889

RESUMO

Bimatoprost is a synthetic prostamide F2α analog that down-regulates adipogenesis in vitro. This effect has been attributed to participation in a negative feedback loop that regulates anandamide-induced adipogenesis. A follow-on investigation has now been conducted into the broader metabolic effects of bimatoprost using rats under both normal state and obesity-inducing conditions. Chronic bimatoprost administration attenuated weight gain in a dose dependent-manner in rats fed either standard [max effect -7%] or obesity-promoting diets [max effect -23%] over a 9-10 week period. Consistent with these findings, bimatoprost promoted satiety as measured by decreased food intake [max effect, -7%], gastric emptying [max effect, -33-50%] and decreased circulating concentrations of the gut hormones, ghrelin and GLP-1 [max effect, -33-50%]. Additionally, subcutaneous, and visceral fat mass were distinctly affected by treatment [-30% diet independent]. Taken together, these results suggest that bimatoprost regulates energy homeostasis through promoting satiety and a decrease in food intake. These newly reported activities of bimatoprost reveal an additional method of metabolic disease intervention for potential therapeutic exploitation.


Assuntos
Obesidade , Aumento de Peso , Ratos , Animais , Bimatoprost , Obesidade/tratamento farmacológico , Dieta , Adipogenia
16.
Biomedicines ; 10(10)2022 Sep 26.
Artigo em Inglês | MEDLINE | ID: mdl-36289662

RESUMO

Duchenne muscular dystrophy (DMD) is a progressive, X-linked childhood neuromuscular disorder that results from loss-of-function mutations in the DYSTROPHIN gene. DMD patients exhibit muscle necrosis, cardiomyopathy, respiratory failure, and loss of ambulation. One of the major driving forces of DMD disease pathology is chronic inflammation. The current DMD standard of care is corticosteroids; however, there are serious side effects with long-term use, thus identifying novel anti-inflammatory and anti-fibrotic treatments for DMD is of high priority. We investigated the next-generation SINE compound, KPT-8602 (eltanexor) as an oral therapeutic to alleviate dystrophic symptoms. We performed pre-clinical evaluation of the effects of KPT-8602 in DMD zebrafish (sapje) and mouse (D2-mdx) models. KPT-8602 improved dystrophic skeletal muscle pathologies, muscle architecture and integrity, and overall outcomes in both animal models. KPT-8602 treatment ameliorated DMD pathology in D2-mdx mice, with increased locomotor behavior and improved muscle histology. KPT-8602 altered the immunological profile of the dystrophic mice, and reduced circulating osteopontin serum levels. These findings demonstrate KPT-8602 as an effective therapeutic in DMD through by promotion of an anti-inflammatory environment and overall improvement of DMD pathological outcomes.

17.
Opt Express ; 30(19): 33479-33489, 2022 Sep 12.
Artigo em Inglês | MEDLINE | ID: mdl-36242383

RESUMO

OASIS (Orbiting Astronomical Satellite for Investigating Stellar Systems) is a space-based observatory with a 14 m diameter inflatable primary antenna that will perform high spectral resolution observations at terahertz frequencies. The large inflatable aperture, non-traditional surface configuration, and the double layered membrane structure afford unique challenges to the modeling and testing of the primary antenna. A 1-meter prototype of the primary antenna (A1) was built to validate our technical approach. A laser radar coordinate measuring system was adopted to measure the shape of A1. In addition, deflectometry was performed to monitor the stability of A1 during the radar measurement. Test cases pertaining to specific operational conditions expected for the 14 m OASIS primary were explored. The measured data were then compared to the Fichter model and Finite-element Analyzer for Inflatable Membranes (FAIM).

18.
Cells ; 11(19)2022 10 02.
Artigo em Inglês | MEDLINE | ID: mdl-36231073

RESUMO

Adolescence is a developmental period that encompasses, but is not limited to, puberty and continues into early adulthood. During this period, maturation and refinement are observed across brain regions such as the prefrontal cortex (PFC), which is critical for cognitive function. Adolescence is also a time when excessive alcohol consumption in the form of binge drinking peaks, increasing the risk of long-term cognitive deficits and the risk of developing an alcohol use disorder later in life. Animal models have revealed that adolescent ethanol (EtOH) exposure results in protracted disruption of neuronal function and performance on PFC-dependent tasks that require higher-order decision-making. However, the role of astrocytes in EtOH-induced disruption of prefrontal cortex-dependent function has yet to be elucidated. Astrocytes have complex morphologies with an extensive network of peripheral astrocyte processes (PAPs) that ensheathe pre- and postsynaptic terminals to form the 'tripartite synapse.' At the tripartite synapse, astrocytes play several critical roles, including synaptic maintenance, dendritic spine maturation, and neurotransmitter clearance through proximity-dependent interactions. Here, we investigate the effects of adolescent binge EtOH exposure on astrocyte morphology, PAP-synaptic proximity, synaptic stabilization proteins, and dendritic spine morphology in subregions of the PFC that are important in the emergence of higher cognitive function. We found that adolescent binge EtOH exposure resulted in subregion specific changes in astrocyte morphology and astrocyte-neuronal interactions. While this did not correspond to a loss of astrocytes, synapses, or dendritic spines, there was a corresponding region-specific and EtOH-dependent shift in dendritic spine phenotype. Lastly, we found that changes in astrocyte-neuronal interactions were not a consequence of changes in the expression of key synaptic structural proteins neurexin, neuroligin 1, or neuroligin 3. These data demonstrate that adolescent EtOH exposure results in enduring effects on neuron-glia interactions that persist into adulthood in a subregion-specific PFC manner, suggesting selective vulnerability. Further work is necessary to understand the functional and behavioral implications.


Assuntos
Etanol , Maturidade Sexual , Animais , Etanol/toxicidade , Neurônios/metabolismo , Córtex Pré-Frontal , Sinapses/metabolismo
19.
Radiol Clin North Am ; 60(6): 963-978, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36202482

RESUMO

Mosaic attenuation pattern is commonly encountered on high-resolution computed tomography and has myriad causes. These diseases may involve small airways, vessels, alveoli, or interstitium, with some involving compartmental combinations. Small airways disease is caused by cellular bronchiolitis, infiltrated by inflammatory cells or constrictive bronchiolitis, resulting in fibrosis of the small airways. Any acute or chronic cause of ground-glass opacity can result in a mosaic pattern. Vascular causes of mosaic attenuation include chronic thromboembolic pulmonary hypertension and rarely other causes of pulmonary arterial hypertension. Ancillary CT findings along with the clinical history help narrow the differential diangosis. Biopsy is uncommonly required for definitiive diagnosis.


Assuntos
Bronquiolite Obliterante , Bronquiolite , Humanos , Pulmão/diagnóstico por imagem , Alvéolos Pulmonares , Tomografia Computadorizada por Raios X/métodos
20.
J Chem Theory Comput ; 18(10): 6354-6369, 2022 Oct 11.
Artigo em Inglês | MEDLINE | ID: mdl-36179376

RESUMO

Non-biological foldamers are a promising class of macromolecules that share similarities to classical biopolymers such as proteins and nucleic acids. Currently, designing novel foldamers is a non-trivial process, often involving many iterations of trial synthesis and characterization until folded structures are observed. In this work, we aim to tackle these foldamer design challenges using computational modeling techniques. We developed CG PyRosetta, an extension to the popular protein folding python package, PyRosetta, which introduces coarse-grained (CG) residues into PyRosetta, enabling the folding of toy CG foldamer models. Although these models are simplified, they can help explore overarching physical hypotheses about how oligomers can form. Through systematic variation of CG parameters in these models, we can investigate various folding hypotheses at the CG scale to inform the design process of new foldamer chemistries. In this study, we demonstrate CG PyRosetta's ability to identify minimum energy structures with a diverse structural search over a range of simple models, as well as two hypothesis-driven parameter scans investigating the effects of side-chain size and internal backbone angle on secondary structures. We are able to identify several types of secondary structures from single- and double-helices to sheet-like and knot-like structures. We show how side-chain size and backbone bond angle both play an important role in the structure and energetics of these toy models. Optimal side-chain sizes promote favorable packing of side chains, while specific backbone bond angles influence the specific helix type found in folded structures.


Assuntos
Ácidos Nucleicos , Dobramento de Proteína , Modelos Moleculares , Estrutura Secundária de Proteína , Proteínas/química
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