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1.
Genes Dev ; 31(16): 1641-1654, 2017 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-28947497

RESUMO

Tumor suppressor p53 is frequently mutated in human cancer. Mutant p53 often promotes tumor progression through gain-of-function (GOF) mechanisms. However, the mechanisms underlying mutant p53 GOF are not well understood. In this study, we found that mutant p53 activates small GTPase Rac1 as a critical mechanism for mutant p53 GOF to promote tumor progression. Mechanistically, mutant p53 interacts with Rac1 and inhibits its interaction with SUMO-specific protease 1 (SENP1), which in turn inhibits SENP1-mediated de-SUMOylation of Rac1 to activate Rac1. Targeting Rac1 signaling by RNAi, expression of the dominant-negative Rac1 (Rac1 DN), or the specific Rac1 inhibitor NSC23766 greatly inhibits mutant p53 GOF in promoting tumor growth and metastasis. Furthermore, mutant p53 expression is associated with enhanced Rac1 activity in clinical tumor samples. These results uncover a new mechanism for Rac1 activation in tumors and, most importantly, reveal that activation of Rac1 is an unidentified and critical mechanism for mutant p53 GOF in tumorigenesis, which could be targeted for therapy in tumors containing mutant p53.


Assuntos
Carcinogênese/genética , Mutação , Sumoilação , Proteína Supressora de Tumor p53/genética , Proteínas rac1 de Ligação ao GTP/metabolismo , Linhagem Celular , Linhagem Celular Tumoral , Cisteína Endopeptidases/metabolismo , Progressão da Doença , Humanos , Metástase Neoplásica , Neoplasias/enzimologia , Neoplasias/metabolismo , Neoplasias/patologia , Proteína Supressora de Tumor p53/metabolismo
2.
Clin Exp Immunol ; 217(1): 89-98, 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38517050

RESUMO

Excessive formation of neutrophil extracellular traps (NETs) may lead to myositis-related interstitial lung disease (ILD). There is evidence that NETs can directly injure vascular endothelial cells and play a pathogenic role in the inflammatory exudation of ILD. However, the specific mechanism is unclear. This study aimed to investigate the specific mechanism underlying NET-induced injury to human pulmonary microvascular endothelial cells (HPMECs). HPMECs were stimulated with NETs (200 ng/ml) in vitro. Cell death was detected by propidium iodide staining. The morphological changes of the cells were observed by transmission electron microscopy (TEM). Pyroptosis markers were detected by western blot, immunofluorescence, and quantitative real-time polymerase chain reaction, and the related inflammatory factor Interleukin-1ß (IL-1ß) was verified by enzyme-linked immunosorbent assay (ELISA). Compared with the control group, HPMECs mortality increased after NET stimulation, and the number of pyroptosis vacuoles in HPMECs was further observed by TEM. The pulmonary microvascular endothelial cells (PMECs) of the experimental autoimmune myositis mouse model also showed a trend of pyroptosis in vivo. Cell experiment further confirmed the significantly high expression of the NLRP3 inflammasome and pyroptosis-related markers, including GSDMD and inflammatory factor IL-1ß. Pretreated with the NLRP3 inhibitor MCC950, the activation of NLRP3 inflammasome and pyroptosis of HPMECs were effectively inhibited. Our study confirmed that NETs promote pulmonary microvascular endothelial pyroptosis by activating the NLRP3 inflammasome, suggesting that NETs-induced pyroptosis of PMECs may be a potential pathogenic mechanism of inflammatory exudation in ILD.


Assuntos
Células Endoteliais , Armadilhas Extracelulares , Inflamassomos , Pulmão , Proteína 3 que Contém Domínio de Pirina da Família NLR , Piroptose , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo , Armadilhas Extracelulares/metabolismo , Armadilhas Extracelulares/imunologia , Animais , Células Endoteliais/metabolismo , Camundongos , Inflamassomos/metabolismo , Humanos , Pulmão/imunologia , Pulmão/patologia , Interleucina-1beta/metabolismo , Neutrófilos/imunologia , Neutrófilos/metabolismo , Células Cultivadas , Camundongos Endogâmicos C57BL , Microvasos/patologia , Microvasos/imunologia
3.
Immunol Invest ; : 1-14, 2024 Jun 14.
Artigo em Inglês | MEDLINE | ID: mdl-38874911

RESUMO

INTRODUCTION: Mycoplasma pneumoniae (MP) is the most common pathogen of community-acquired pneumonia in children. However, the role of neutrophil extracellular traps (NETs) in the pathogenesis of MP is unclear. METHODS: Both the level of NETs were detected between the 60 MP pneumonia patients and 20 healthy controls, whose the clinical characteristics were compared. Additionally, NETs formation induced by community-acquired respiratory distress syndrome (CARDS) toxin was also analyzed through transcriptome sequencing. RESULTS: The levels of cell-free DNA, Cit-H3, and MPO-DNA complexes were significantly increased in the patients with MP pneumonia. Importantly, both cell-free DNA and LDH were higher in hospitalized patients with severity than those without severity. In addition, CARDS toxin induced the NETs formation in vitro and in vivo. Transcriptomics GO and KEGG pathway analysis indicate that NOD like receptor signaling pathway and Toll-like receptor signaling pathway are significantly enriched. Finally, we found that DNase I significantly attenuated the higher levels of Cit-H3, and up-regulation of interleukin-1ß (IL-1ß) and interleukin-18 (IL-18) by down-regulating the expression of NLRP3 and Caspase1(p20) in the lung tissues. DISCUSSION: These results indicate that inhibiting excessive activation of NLRP3 inflammasomes, and NETs formation may alleviate MP pneumonia.

4.
J Neuropsychiatry Clin Neurosci ; 36(1): 36-44, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-37667629

RESUMO

OBJECTIVE: A significant number of patients develop anxiety after stroke. The objective of this study was to identify risk factors for anxiety after hemorrhagic stroke that may facilitate diagnosis and treatment. METHODS: Patients admitted between January 2015 and February 2021 with nontraumatic hemorrhagic stroke (intracerebral [ICH] or subarachnoid [SAH] hemorrhage) were assessed telephonically 3 and 12 months after stroke with the Quality of Life in Neurological Disorders Anxiety Short Form to evaluate the relationships between poststroke anxiety (T score >50) and preclinical social and neuropsychiatric history, systemic and neurological illness severity, and in-hospital complications. RESULTS: Of 71 patients who completed the 3-month assessment, 28 (39%) had anxiety. There was a difference in Glasgow Coma Scale (GCS) scores on admission between patients with anxiety (median=14, interquartile range [IQR]=12-15) and those without anxiety (median=15, IQR=14-15) (p=0.034), and the incidence of anxiety was higher among patients with ICH (50%) than among those with SAH (20%) (p=0.021). Among patients with ICH, anxiety was associated with larger median ICH volume (25 cc [IQR=8-46] versus 8 cc [IQR=3-13], p=0.021) and higher median ICH score (2 [IQR=1-3] versus 1 [IQR=0-1], p=0.037). On multivariable analysis with GCS score, hemorrhage type, and neuropsychiatric history, only hemorrhage type remained significant (odds ratio=3.77, 95% CI=1.19-12.05, p=0.024). Of the 39 patients who completed the 12-month assessment, 12 (31%) had anxiety, and there was a difference in mean National Institutes of Health Stroke Scale scores between patients with (5 [IQR=3-12]) and without (2 [IQR=0-4]) anxiety (p=0.045). There was fair agreement (κ=0.38) between the presence of anxiety at 3 and 12 months. CONCLUSIONS: Hemorrhage characteristics and factors assessed with neurological examination on admission are associated with the development of poststroke anxiety.


Assuntos
Acidente Vascular Cerebral Hemorrágico , Acidente Vascular Cerebral , Hemorragia Subaracnóidea , Humanos , Hemorragia Cerebral/complicações , Hemorragia Cerebral/epidemiologia , Acidente Vascular Cerebral Hemorrágico/complicações , Qualidade de Vida , Hemorragia Subaracnóidea/complicações , Hemorragia Subaracnóidea/epidemiologia , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/epidemiologia , Ansiedade/epidemiologia , Ansiedade/etiologia , Fatores de Risco
5.
J Neuropsychiatry Clin Neurosci ; : appineuropsych20230114, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38650464

RESUMO

OBJECTIVE: Emotional and behavioral dyscontrol (EBD), a neuropsychiatric complication of stroke, leads to patient and caregiver distress and challenges to rehabilitation. Studies of neuropsychiatric sequelae in stroke are heavily weighted toward ischemic stroke. This study was designed to compare risk of EBD following intracerebral hemorrhage (ICH) and subarachnoid hemorrhage (SAH) and to identify risk factors for EBD following hemorrhagic stroke. METHODS: The authors conducted a prospective cohort study of patients hospitalized for nontraumatic hemorrhagic stroke between 2015 and 2021. Patients or legally authorized representatives completed the Quality of Life in Neurological Disorders (Neuro-QOL) EBD short-form inventory 3 months after hospitalization. Univariable and multivariable analyses identified risk factors for EBD after hemorrhagic stroke. RESULTS: The incidence of EBD was 21% (N=15 of 72 patients) at 3 months after hemorrhagic stroke. Patients with ICH were more likely to develop EBD; 93% of patients with EBD (N=14 of 15) had ICH compared with 56% of patients without EBD (N=32 of 57). The median Glasgow Coma Scale (GCS) score at hospital admission was lower among patients who developed EBD (13 vs. 15 among those without EBD). Similarly, admission scores on the National Institutes of Health Stroke Scale (NIHSS) and the Acute Physiology and Chronic Health Evaluation II (APACHE II) were higher among patients with EBD (median NIHSS score: 7 vs. 2; median APACHE II score: 17 vs. 11). Multivariable analyses identified hemorrhage type (ICH) and poor admission GCS score as predictors of EBD 3 months after hemorrhagic stroke. CONCLUSIONS: Patients with ICH and a low GCS score at admission are at increased risk of developing EBD 3 months after hemorrhagic stroke and may benefit from early intervention.

6.
Mem Cognit ; 52(2): 312-333, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37782444

RESUMO

Elucidating the interaction between lexical processing and word learning is essential for a complete understanding of the underlying mechanisms of each of them. Long-term priming for words reflects an interplay between lexical processing and word learning. Although robust long-term priming effects have been found between two occurrences of the same word and between semantically similar words, it remains unclear whether long-term priming between orthographically similar words (i.e., long-term form priming) is a reliable effect. Following the theoretical analysis based on the connectionist framework, we articulated the possibility that long-term form priming might be modulated by the phonological congruency between the prime and target words, and that if this modulator was under control, reliable effects of long-term form priming would emerge. However, this hypothesis has not been adequately tested empirically. The present study tested this hypothesis by using Chinese phonograms and the phonetic radicals embedded in them as the prime and target items. In three experiments that varied in the types of stimuli and testing tasks, we consistently found that when the prime and target had the same phonology, naming the prime facilitated later processing of the target, while when they had different phonologies, the priming effect was inhibitory. These observations were consistent with the connectionist account of long-term priming for words. Our findings help confirm the reliability, generalizability, and robustness of long-term form priming and elucidate its underlying mechanisms, and suggesting promising future directions on the interactions between lexical processing and word learning.


Assuntos
Fonética , Aprendizagem Verbal , Humanos , Reprodutibilidade dos Testes
7.
Genes Dev ; 30(17): 1956-70, 2016 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-27664236

RESUMO

Increased lipid synthesis is a key characteristic of many cancers that is critical for cancer progression. ATP-citrate lyase (ACLY), a key enzyme for lipid synthesis, is frequently overexpressed or activated in cancer to promote lipid synthesis and tumor progression. Cullin3 (CUL3), a core protein for the CUL3-RING ubiquitin ligase complex, has been reported to be a tumor suppressor and frequently down-regulated in lung cancer. Here, we found that CUL3 interacts with ACLY through its adaptor protein, KLHL25 (Kelch-like family member 25), to ubiquitinate and degrade ACLY in cells. Through negative regulation of ACLY, CUL3 inhibits lipid synthesis, cell proliferation, and xenograft tumor growth of lung cancer cells. Furthermore, ACLY inhibitor SB-204990 greatly abolishes the promoting effect of CUL3 down-regulation on lipid synthesis, cell proliferation, and tumor growth. Importantly, low CUL3 expression is associated with high ACLY expression and poor prognosis in human lung cancer. In summary, our results identify CUL3-KLHL25 ubiquitin ligase as a novel negative regulator for ACLY and lipid synthesis and demonstrate that decreased CUL3 expression is an important mechanism for increased ACLY expression and lipid synthesis in lung cancer. These results also reveal that negative regulation of ACLY and lipid synthesis is a novel and critical mechanism for CUL3 in tumor suppression.


Assuntos
ATP Citrato (pro-S)-Liase/metabolismo , Proteínas de Transporte/metabolismo , Proteínas Culina/metabolismo , Regulação Neoplásica da Expressão Gênica , Neoplasias Pulmonares/fisiopatologia , Células A549 , Animais , Proteínas de Transporte/genética , Linhagem Celular Tumoral , Proliferação de Células/genética , Proteínas Culina/genética , Progressão da Doença , Humanos , Metabolismo dos Lipídeos/genética , Lipídeos/biossíntese , Neoplasias Pulmonares/enzimologia , Neoplasias Pulmonares/genética , Masculino , Camundongos Endogâmicos BALB C , Proteólise
8.
J Stroke Cerebrovasc Dis ; : 107830, 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38909872

RESUMO

OBJECTIVES: The objective of this study was to determine factors associated with negative disease-related stigma after hemorrhagic stroke. MATERIALS AND METHODS: Patients with non-traumatic hemorrhage (ICH or SAH) admitted between January 2015 and February 2021 were assessed by telephone 3-months after discharge using the Quality of Life in Neurological Disorders (Neuro-QoL) Negative Disease-Related Stigma Short Form inventory. We evaluated the relationship between disease-related stigma (T-score>50) and pre-stroke demographics, admission data, and poor functional outcome (3-month mRS score 3-5 and Barthel Index <100). RESULTS: We included 89 patients (56 ICH and 33 SAH). The median age was 63 (IQR 50-69), 43% were female, and 67% graduated college. Admission median GCS score was 15 (IQR 13-15) and APACHE II score was 12 (IQR 9-17). 31% had disease-related stigma. On univariate analysis, disease-related stigma was associated with female sex, non-completion of college, GCS score, APACHE II score, and 3-month mRS score (all p<0.05). On multivariate analysis, disease-related stigma was associated with female sex (OR = 3.72, 95% CI = 1.23-11.25, p = 0.02) and 3-month Barthel Index<100 (OR = 3.46, 95% CI = 1.13-10.64, p = 0.03) on one model, and female sex (OR = 3.75, 95% CI = 1.21-11.58, p = 0.02) and 3-month mRS score 3-5 (OR = 4.23, 95% CI = 1.21-14.75, p = 0.02) on a second model. CONCLUSION: Functional outcome and female sex are associated with disease-related stigma 3-months after hemorrhagic stroke. Because stigma may negatively affect recovery, there is a need to understand the relationship between these factors to mitigate stroke-related stigma.

9.
Angew Chem Int Ed Engl ; 63(15): e202400590, 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38318728

RESUMO

Polymer solar cells (PSCs) rely on a blend of small molecular acceptors (SMAs) with polymer donors, where thermodynamic relaxation of SMAs poses critical concerns on operational stability. To tackle this issue, tethered SMAs, wherein multiple SMA-subunits are connected to the aromatic-core via flexible chains, are proposed. This design aims to an elevated glass transition temperature (Tg) for a dynamical control. However, attaining an elevated Tg value with additional SMA subunits introduces complexity to the molecular packing, posing a significant challenge in realizing both high stability and power conversion efficiency (PCE). In this study, we initiate isomer engineering on the benzene-carboxylate core and find that meta-positioned dimeric BDY-ß exhibits more favorable molecular packing compared to its para-positioned counterpart, BDY-α. With this encouraging result, we expand our approach by introducing an additional SMA unit onto the aromatic core of BDY-ß, maintaining a meta-position relative to each SMA unit location in the tethered acceptor. This systematic aromatic-core engineering results in a star-shaped C3h-positioned molecular geometry. The supramolecular interactions of SMA units in the trimer contribute to enhancements in Tg value, crystallinity, and a red-shifted absorption compared to dimers. These characteristics result in a noteworthy increase in PCE to 18.24 %, coupled with a remarkable short-circuit current density of 27.06 mA cm-2. More significantly, the trimer-based devices delivered an excellent thermal stability with over 95 % of their initial efficiency after 1200 h thermal degradation. Our findings underscore the promise and feasibility of tethered trimeric structures in achieving highly ordered aggregation behavior and increased Tg value in PSCs, simultaneously improving in device efficiency and thermal stability.

10.
Int J Mol Sci ; 24(17)2023 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-37686142

RESUMO

As a novel form of regulated cell death, ferroptosis is characterized by intracellular iron and lipid peroxide accumulation, which is different from other regulated cell death forms morphologically, biochemically, and immunologically. Ferroptosis is regulated by iron metabolism, lipid metabolism, and antioxidant defense systems as well as various transcription factors and related signal pathways. Emerging evidence has highlighted that ferroptosis is associated with many physiological and pathological processes, including cancer, neurodegeneration diseases, cardiovascular diseases, and ischemia/reperfusion injury. Noncoding RNAs are a group of functional RNA molecules that are not translated into proteins, which can regulate gene expression in various manners. An increasing number of studies have shown that noncoding RNAs, especially miRNAs, lncRNAs, and circRNAs, can interfere with the progression of ferroptosis by modulating ferroptosis-related genes or proteins directly or indirectly. In this review, we summarize the basic mechanisms and regulations of ferroptosis and focus on the recent studies on the mechanism for different types of ncRNAs to regulate ferroptosis in different physiological and pathological conditions, which will deepen our understanding of ferroptosis regulation by noncoding RNAs and provide new insights into employing noncoding RNAs in ferroptosis-associated therapeutic strategies.


Assuntos
Ferroptose , RNA Longo não Codificante , Morte Celular Regulada , Ferroptose/genética , RNA não Traduzido/genética , RNA Longo não Codificante/genética , Ferro
11.
Phys Rev Lett ; 129(1): 011805, 2022 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-35841564

RESUMO

The diphoton channel at lepton colliders, e^{+}e^{-}(µ^{+}µ^{-})→γγ, has a remarkable feature that the leading new physics contribution comes only from dimension-eight operators. This contribution is subject to a set of positivity bounds, derived from the fundamental principles of quantum field theory, such as unitarity, locality, analyticity and Lorentz invariance. These positivity bounds are thus applicable to the most direct observable: the diphoton cross section. This unique feature provides a clear, robust, and unambiguous test of these principles. We estimate the capability of various future lepton colliders in probing the dimension-eight operators and testing the positivity bounds in this channel. We show that positivity bounds can lift certain flat directions among the effective operators and significantly change the perspectives of a global analysis. We also discuss the positivity bounds of the Zγ/ZZ processes which are related to the γγ ones, but are more complicated due to the massive Z boson.

12.
Neurocrit Care ; 36(3): 955-963, 2022 06.
Artigo em Inglês | MEDLINE | ID: mdl-34918215

RESUMO

BACKGROUND: The association between race and ethnicity and microvascular disease in patients with intracerebral hemorrhage (ICH) is unclear. We hypothesized that social determinants of health (SDOHs) mediate the relationship between race and ethnicity and severity of white matter hyperintensities (WMHs) and microbleeds in patients with ICH. METHODS: We performed a retrospective observational cohort study of patients with ICH at two tertiary care hospitals between 2013 and 2020 who underwent magnetic resonance imaging of the brain. Magnetic resonance imaging scans were evaluated for the presence of microbleeds and WMH severity (defined by the Fazekas scale; moderate to severe WMH defined as Fazekas scores 3-6). We assessed for associations between sex, race and ethnicity, employment status, median household income, education level, insurance status, and imaging biomarkers of microvascular disease. A mediation analysis was used to investigate the influence of SDOHs on the associations between race and imaging features. We assessed the relationship of all variables with discharge outcomes. RESULTS: We identified 233 patients (mean age 62 [SD 16]; 48% female) with ICH. Of these, 19% were Black non-Hispanic, 32% had a high school education or less, 21% required an interpreter, 11% were unemployed, and 6% were uninsured. Moderate to severe WMH, identified in 114 (50%) patients, was associated with age, Black non-Hispanic race and ethnicity, highest level of education, insurance status, and history of hypertension, hyperlipidemia, or diabetes (p < 0.05). In the mediation analysis, the proportion of the association between Black non-Hispanic race and ethnicity and the Fazekas score that was mediated by highest level of education was 65%. Microbleeds, present in 130 (57%) patients, was associated with age, highest level of education, and history of diabetes or hypertension (p < 0.05). Age, highest level of education, insurance status, and employment status were associated with discharge modified Rankin Scale scores of 3-6, but race and ethnicity was not. CONCLUSIONS: The association between Black non-Hispanic race and ethnicity and moderate to severe WMH lost significance after we adjusted for highest level of education, suggesting that SDOHs may mediate the association between race and ethnicity and microvascular disease.


Assuntos
Hipertensão , Leucoaraiose , Substância Branca , Hemorragia Cerebral/complicações , Hemorragia Cerebral/diagnóstico por imagem , Etnicidade , Feminino , Humanos , Hipertensão/complicações , Hipertensão/epidemiologia , Leucoaraiose/complicações , Imageamento por Ressonância Magnética , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Determinantes Sociais da Saúde
13.
J Stroke Cerebrovasc Dis ; 31(8): 106492, 2022 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-35594604

RESUMO

BACKGROUND: To identify opportunities to improve morbidity after hemorrhagic stroke, it is imperative to understand factors that are related to psychological outcome. DESIGN/METHODS: We prospectively identified patients with non-traumatic hemorrhagic stroke (intracerebral or subarachnoid hemorrhage) between January 2015 and February 2021 who were alive 3-months after discharge and telephonically assessed 1) psychological outcome using the Quality of Life in Neurological Disorders anxiety, depression, emotional and behavioral dyscontrol, fatigue and sleep disturbance inventories and 2) functional outcome using the modified Rankin Scale (mRS) and Barthel Index. We also identified discharge destination for all patients. We then evaluated the relationship between abnormal psychological outcomes (T-score >50) and discharge destination other than home, poor 3-month mRS score defined as 3-5 and poor 3-month Barthel Index defined as <100. RESULTS: 73 patients were included; 41 (56%) had an abnormal psychological outcome on at least one inventory. There were 41 (56%) patients discharged to a destination other than home, 44 (63%) with poor mRS score and 28 (39%) with poor Barthel Index. Anxiety, depression, emotional and behavioral dyscontrol and sleep disturbance were all associated with a destination other than home, poor mRS score, and poor Barthel Index (all p<0.05). Fatigue was related to poor mRS score and poor Barthel Index (p=0.005 and p=0.006, respectively). CONCLUSION: Multiple psychological outcomes 3-months after hemorrhagic stroke are related to functional status. Interventions to improve psychological outcome and reduce morbidity in patients with poor functional status should be explored by the interdisciplinary team.


Assuntos
Acidente Vascular Cerebral Hemorrágico , Acidente Vascular Cerebral , Fadiga/diagnóstico , Fadiga/etiologia , Estado Funcional , Acidente Vascular Cerebral Hemorrágico/diagnóstico , Acidente Vascular Cerebral Hemorrágico/terapia , Humanos , Qualidade de Vida , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/terapia , Resultado do Tratamento
14.
J Neurosci ; 40(37): 7065-7079, 2020 09 09.
Artigo em Inglês | MEDLINE | ID: mdl-32817065

RESUMO

The crumbs (crb) apical polarity genes are essential for the development and functions of epithelia. Adult zebrafish retinal neuroepithelium expresses three crb genes (crb1, crb2a, and crb2b); however, it is unknown whether and how Crb1 differs from other Crb proteins in expression, localization, and functions. Here, we show that, unlike zebrafish Crb2a and Crb2b as well as mammalian Crb1 and Crb2, zebrafish Crb1 does not localize to the subapical regions of photoreceptors and Müller glial cells; rather, it localizes to a small region of cone outer segments: the cell membranes surrounding the axonemes. Moreover, zebrafish Crb1 is not required for retinal morphogenesis and photoreceptor patterning. Interestingly, Crb1 promotes rod survival under strong white light irradiation in a previously unreported non--cell-autonomous fashion; in addition, Crb1 delays UV and blue cones' chromatin condensation caused by UV light irradiation. Finally, Crb1 plays a role in cones' responsiveness to light through an arrestin-translocation-independent mechanism. The localization of Crb1 and its functions do not differ between male and female fish. We conclude that zebrafish Crb1 has diverged from other vertebrate Crb proteins, representing a neofunctionalization in Crb biology during evolution.SIGNIFICANCE STATEMENT Apicobasal polarity of epithelia is an important property that underlies the morphogenesis and functions of epithelial tissues. Epithelial apicobasal polarity is controlled by many polarity genes, including the crb genes. In vertebrates, multiple crb genes have been identified, but the differences in their expression patterns and functions are not fully understood. Here, we report a novel subcellular localization of zebrafish Crb1 in retinal cone photoreceptors and evidence for its new functions in photoreceptor maintenance and light responsiveness. This study expands our understanding of the biology of the crb genes in epithelia, including retinal neuroepithelium.


Assuntos
Axonema/metabolismo , Proteínas do Tecido Nervoso/metabolismo , Células Fotorreceptoras Retinianas Cones/metabolismo , Visão Ocular , Proteínas de Peixe-Zebra/metabolismo , Animais , Membrana Celular/metabolismo , Membrana Celular/fisiologia , Cromatina/metabolismo , Feminino , Masculino , Proteínas do Tecido Nervoso/genética , Transporte Proteico , Células Fotorreceptoras Retinianas Cones/fisiologia , Células Fotorreceptoras Retinianas Cones/efeitos da radiação , Raios Ultravioleta/efeitos adversos , Peixe-Zebra , Proteínas de Peixe-Zebra/genética
15.
Stroke ; 52(6): e217-e223, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33902301

RESUMO

Background and Purpose: Antiplatelet therapy is key for preventing thrombotic events after transient ischemic attack or ischemic stroke. Although the role of aspirin is well established, there is emerging evidence for the role of short-term dual antiplatelet therapy (DAPT) in preventing recurrent stroke. Methods: We conducted a systematic review and study-level meta-analyses of randomized controlled trials comparing outcomes of early initiation of short-term DAPT (aspirin+P2Y12 inhibitor for up to 3 months) versus aspirin alone in patients with acute stroke or transient ischemic attack. Primary efficacy outcome was risk of recurrent stroke and primary safety outcome was incidence of major bleeding. Secondary outcomes studied were risk of any ischemic stroke, hemorrhagic stroke, major adverse cardiovascular events, and all-cause death. Pooled risk ratios (RRs) and CIs were calculated using a random-effects model. Results: Four trials with a total of 21 459 patients were included. As compared to aspirin alone, DAPT had a lower risk of recurrent stroke (RR, 0.76 [95% CI, 0.68­0.83]; P<0.001; I2=0%) but a higher risk of major bleeding events (RR, 2.22 [95% CI, 1.14­4.34], P=0.02, I2=46.5%). Patients receiving DAPT had a lower risk of major adverse cardiovascular events (RR, 0.76 [95% CI, 0.69­0.84], P<0.001, I2=0%) and recurrent ischemic events (RR, 0.74 [95% CI, 0.67­0.82], P<0.001, I2=0%). Conclusions: As compared to aspirin alone, short-term DAPT within 24 hours of high-risk transient ischemic attack or mild-moderate ischemic stroke reduces the risk of recurrent stroke at the expense of higher risk of major bleeding.


Assuntos
Aspirina/administração & dosagem , Terapia Antiplaquetária Dupla/métodos , Ataque Isquêmico Transitório/tratamento farmacológico , Inibidores da Agregação Plaquetária/administração & dosagem , Ensaios Clínicos Controlados Aleatórios como Assunto/métodos , Acidente Vascular Cerebral/tratamento farmacológico , Aspirina/efeitos adversos , Terapia Antiplaquetária Dupla/efeitos adversos , Hemorragia/induzido quimicamente , Hemorragia/diagnóstico , Humanos , Ataque Isquêmico Transitório/diagnóstico , Inibidores da Agregação Plaquetária/efeitos adversos , Acidente Vascular Cerebral/diagnóstico , Tempo para o Tratamento
16.
Phys Rev Lett ; 127(12): 121601, 2021 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-34597073

RESUMO

We discuss the general method for obtaining full positivity bounds on multifield effective field theories (EFTs). While the leading order forward positivity bounds are commonly derived from the elastic scattering of two (superposed) external states, we show that, for a generic EFT containing three or more low-energy modes, this approach only gives incomplete bounds. We then identify the allowed parameter space as the dual to a spectrahedron, constructed from crossing symmetries of the amplitude, and show that finding the optimal bounds for a given number of modes is equivalent to a geometric problem: finding the extremal rays of a spectrahedron. We show how this is done analytically for simple cases and numerically formulated as semidefinite programming (SDP) problems for more complicated cases. We demonstrate this approach with a number of well-motivated examples in particle physics and cosmology, including EFTs of scalars, vectors, fermions, and gravitons. In all these cases, we find that the SDP approach leads to results that either improve the previous ones or are completely new. We also find that the SDP approach is numerically much more efficient.

17.
J Stroke Cerebrovasc Dis ; 30(8): 105870, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-34077823

RESUMO

OBJECTIVES: Systemic inflammatory response syndrome (SIRS) and hematoma expansion are independently associated with worse outcomes after intracerebral hemorrhage (ICH), but the relationship between SIRS and hematoma expansion remains unclear. MATERIALS AND METHODS: We performed a retrospective review of patients admitted to our hospital from 2013 to 2020 with primary spontaneous ICH with at least two head CTs within the first 24 hours. The relationship between SIRS and hematoma expansion, defined as ≥6 mL or ≥33% growth between the first and second scan, was assessed using univariable and multivariable regression analysis. We assessed the relationship of hematoma expansion and SIRS on discharge mRS using mediation analysis. RESULTS: Of 149 patients with ICH, 83 (56%; mean age 67±16; 41% female) met inclusion criteria. Of those, 44 (53%) had SIRS. Admission systolic blood pressure (SBP), temperature, antiplatelet use, platelet count, initial hematoma volume and rates of infection did not differ between groups (all p>0.05). Hematoma expansion occurred in 15/83 (18%) patients, 12 (80%) of whom also had SIRS. SIRS was significantly associated with hematoma expansion (OR 4.5, 95% CI 1.16 - 17.39, p= 0.02) on univariable analysis. The association remained statistically significant after adjusting for admission SBP and initial hematoma volume (OR 5.72, 95% CI 1.40 - 23.41, p= 0.02). There was a significant indirect effect of SIRS on discharge mRS through hematoma expansion. A significantly greater percentage of patients with SIRS had mRS 4-6 at discharge (59 vs 33%, p=0.02). CONCLUSION: SIRS is associated with hematoma expansion of ICH within the first 24 hours, and hematoma expansion mediates the effect of SIRS on poor outcome.


Assuntos
Hemorragia Cerebral/complicações , Hematoma/etiologia , Síndrome de Resposta Inflamatória Sistêmica/complicações , Idoso , Idoso de 80 Anos ou mais , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/terapia , Avaliação da Deficiência , Progressão da Doença , Feminino , Estado Funcional , Hematoma/diagnóstico por imagem , Hematoma/terapia , Humanos , Masculino , Pessoa de Meia-Idade , Admissão do Paciente , Prognóstico , Estudos Retrospectivos , Medição de Risco , Fatores de Risco , Síndrome de Resposta Inflamatória Sistêmica/diagnóstico , Síndrome de Resposta Inflamatória Sistêmica/terapia
18.
J Stroke Cerebrovasc Dis ; 30(4): 105618, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33482571

RESUMO

Recurrent episodes of neurological dysfunction and white matter lesions in a young adult raise suspicion for multiple sclerosis (MS). However, occlusive retinopathy, hearing loss and absence of CSF oligoclonal bands are atypical for MS and should make the clinician consider an alternative diagnosis. We describe a man with hearing loss, visual signs and symptoms, and an accumulating burden of brain lesions, who was treated for a clinical diagnosis of MS for nearly two decades. Genetic testing revealed a unifying diagnosis.


Assuntos
Sequenciamento do Exoma , Perda Auditiva Unilateral/etiologia , Doença da Hemoglobina SC/diagnóstico , Hemoglobinas Anormais/genética , Leucoencefalopatias/etiologia , Esclerose Múltipla/diagnóstico , Transtornos da Visão/etiologia , Erros de Diagnóstico , Predisposição Genética para Doença , Perda Auditiva Unilateral/diagnóstico , Perda Auditiva Unilateral/fisiopatologia , Doença da Hemoglobina SC/complicações , Doença da Hemoglobina SC/genética , Humanos , Leucoencefalopatias/diagnóstico por imagem , Leucoencefalopatias/fisiopatologia , Imageamento por Ressonância Magnética , Masculino , Esclerose Múltipla/complicações , Esclerose Múltipla/tratamento farmacológico , Fenótipo , Valor Preditivo dos Testes , Transtornos da Visão/diagnóstico , Transtornos da Visão/fisiopatologia , Adulto Jovem
19.
Phys Rev Lett ; 125(20): 201601, 2020 Nov 13.
Artigo em Inglês | MEDLINE | ID: mdl-33258659

RESUMO

We present a convex geometry perspective to the effective field theory (EFT) parameter space. We show that the second s derivatives of the forward EFT amplitudes form a convex cone, whose extremal rays are closely connected with states in the UV theory. For tree-level UV completions, these rays are simply theories with all UV particles living in at most one irreducible representation of the symmetries of the theory. In addition, all the extremal rays are determined by the symmetries and can be systematically identified via group theoretical considerations. The implications are twofold. First, geometric information encoded in the EFT space can help reconstruct the UV completion. In particular, we will show that the dim-8 operators are important in reverse engineering the UV physics from the standard model EFT and, thus, deserve more theoretical and experimental investigations. Second, theoretical bounds on the Wilson coefficients can be obtained by identifying the boundaries of the cone and are, in general, stronger than the current positivity bounds. We show explicit examples of these new bounds and demonstrate that they originate from the scattering amplitudes corresponding to entangled states.

20.
J Emerg Med ; 58(3): e133-e136, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31806434

RESUMO

BACKGROUND: Patients who present emergently with focal neurological deficits concerning for acute ischemic stroke can be extremely challenging to diagnose and treat. Unnecessary administration of thrombolytics to potential stroke patients whose symptoms are not caused by an acute ischemic stroke-stroke mimics-may result in patient harm, although the overall risk of hemorrhagic complications among stroke mimics is low. CASE REPORT: We present a case of a stroke mimic patient with underlying psychiatric disease who was treated with intravenous alteplase on four separate occasions in four different emergency departments in the same city. Although he did not suffer hemorrhagic complications, this case highlights the importance of rapid exchange of health information across institutions to improve diagnostic quality and safety. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Increased awareness of stroke mimics by emergency physicians may improve diagnostic safety for a subset of high-risk patients. Establishing rapid cross-institutional communication pathways that are integrated into provider's workflows to convey essential patient health information has potential to improve stroke diagnostic decision-making and thus represents an important topic for health systems research in emergency medicine.


Assuntos
Isquemia Encefálica , Acidente Vascular Cerebral , Terapia Trombolítica , Ativador de Plasminogênio Tecidual/administração & dosagem , Administração Intravenosa , Isquemia Encefálica/tratamento farmacológico , Serviço Hospitalar de Emergência , Fibrinolíticos/administração & dosagem , Humanos , Masculino , Pessoa de Meia-Idade , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/tratamento farmacológico , Resultado do Tratamento
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