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BACKGROUND: The efficacy of extracorporeal membrane oxygenation (ECMO) as a bridge to left ventricular assist device (LVAD) remains unclear, and recipients of the more contemporary HeartMate 3 (HM3) LVAD are not well represented in previous studies. We therefore undertook a multicenter, retrospective study of this population. METHODS AND RESULTS: INTERMACS 1 LVAD recipients from five U.S. centers were included. In-hospital and one-year outcomes were recorded. The primary outcome was the overall mortality hazard comparing ECMO versus non-ECMO patients by propensity-weighted survival analysis. Secondary outcomes included survival by LVAD type, as well as postoperative and one-year outcomes. One hundred and twenty-seven patients were included; 24 received ECMO as a bridge to LVAD. Mortality was higher in patients bridged with ECMO in the primary analysis (HR 3.22 [95%CI 1.06-9.77], p = 0.039). Right ventricular assist device was more common in the ECMO group (ECMO: 54.2% vs non-ECMO: 11.7%, p < 0.001). Ischemic stroke was higher at one year in the ECMO group (ECMO: 25.0% vs non-ECMO: 4.9%, p = 0.006). Among the study cohort, one-year mortality was lower in HM3 than in HeartMate II (HMII) or HeartWare HVAD (10.5% vs 46.9% vs 31.6%, respectively; p < 0.001) recipients. Pump thrombosis at one year was lower in HM3 than in HMII or HVAD (1.8% vs 16.1% vs 16.2%, respectively; p = 0.026) recipients. CONCLUSIONS: Higher mortality was observed with ECMO as a bridge to LVAD, likely due to higher acuity illness, yet acceptable one-year survival was seen compared with historical rates. The receipt of the HM3 was associated with improved survival compared with older generation devices.
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Oxigenação por Membrana Extracorpórea , Coração Auxiliar , Choque Cardiogênico , Humanos , Oxigenação por Membrana Extracorpórea/mortalidade , Oxigenação por Membrana Extracorpórea/métodos , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Choque Cardiogênico/terapia , Choque Cardiogênico/mortalidade , Idoso , Resultado do Tratamento , Adulto , Estados Unidos/epidemiologia , Mortalidade HospitalarRESUMO
Wnt signaling regulates gastric stem cell proliferation and differentiation. Although similar Wnt gradients exist within the corpus and antrum of the human stomach, there are striking differences in gland architecture and disease manifestation that suggest Wnt may differentially regulate progenitor cell function in each compartment. In this study, we tested sensitivities to Wnt activation in human gastric corpus and antral organoids to determine whether progenitor cells have region-specific differences in Wnt responsiveness. Human patient-matched corpus and antral organoids were grown in the presence of varying concentrations of the Wnt pathway activator CHIR99021 to assess regional sensitivity to Wnt signaling on growth and proliferation. Corpus organoids were further studied to understand how high Wnt affected cellular differentiation and progenitor cell function. A lower concentration of CHIR99021 stimulated peak growth in corpus organoids compared with patient-matched antral organoids. Supramaximal Wnt signaling levels in corpus organoids suppressed proliferation, altered morphology, reduced surface cell differentiation, and increased differentiation of deep glandular neck and chief cells. Surprisingly, corpus organoids grown in high CHIR99021 had enhanced organoid forming potential, indicating that progenitor cell function was maintained in these nonproliferative, deep glandular cell-enriched organoids. Passaging high-Wnt quiescent organoids into low Wnt rescued normal growth, morphology, and surface cell differentiation. Our findings suggest that human corpus progenitor cells have a lower threshold for optimal Wnt signaling than antral progenitor cells. We demonstrate that Wnt signaling in the corpus regulates a bimodal axis of differentiation, with high Wnt promoting deep glandular cell differentiation and suppressing proliferation while simultaneously promoting progenitor cell function.NEW & NOTEWORTHY This study demonstrates that human gastric corpus organoids have a lower Wnt signaling threshold to drive optimal growth relative to patient-matched antral organoids. Paradoxically, supramaximal Wnt levels suppress corpus organoid proliferation, yet promote differentiation toward deep glandular cell types while simultaneously enhancing progenitor cell function. These findings provide novel insights into how Wnt signaling differentially regulates homeostasis in the human gastric corpus and antrum and contextualizes patterns of Wnt activation diseases.
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Estômago , Via de Sinalização Wnt , Humanos , Células-Tronco , Diferenciação Celular/fisiologia , Organoides/metabolismoRESUMO
Infectious diseases can cause steep declines in wildlife populations, leading to changes in genetic diversity that may affect the susceptibility of individuals to infection and the overall resilience of populations to pathogen outbreaks. Here, we examine evidence for a genetic bottleneck in a population of American crows (Corvus brachyrhynchos) before and after the emergence of West Nile virus (WNV). More than 50% of marked birds in this population were lost over the 2-year period of the epizootic, representing a 10-fold increase in adult mortality. Using analyses of single-nucleotide polymorphisms (SNPs) and microsatellite markers, we tested for evidence of a genetic bottleneck and compared levels of inbreeding and immigration in the pre- and post-WNV populations. Counter to expectations, genetic diversity (allelic diversity and the number of new alleles) increased after WNV emergence. This was likely due to increases in immigration, as the estimated membership coefficients were lower in the post-WNV population. Simultaneously, however, the frequency of inbreeding appeared to increase: Mean inbreeding coefficients were higher among SNP markers, and heterozygosity-heterozygosity correlations were stronger among microsatellite markers, in the post-WNV population. These results indicate that loss of genetic diversity at the population level is not an inevitable consequence of a population decline, particularly in the presence of gene flow. The changes observed in post-WNV crows could have very different implications for their response to future pathogen risks, potentially making the population as a whole more resilient to a changing pathogen community, while increasing the frequency of inbred individuals with elevated susceptibility to disease.
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Doenças das Aves , Corvos , Febre do Nilo Ocidental , Vírus do Nilo Ocidental , Animais , Corvos/genética , Emigração e Imigração , Variação Genética , Febre do Nilo Ocidental/genética , Febre do Nilo Ocidental/veterinária , Febre do Nilo Ocidental/epidemiologia , Vírus do Nilo Ocidental/genéticaRESUMO
OBJECTIVE: The prevalence of multi-drug resistant organism (MDRO) colonization in nursing home residents has been well documented, but little is known about the impact of MDRO bloodstream infections (BSIs). The aim of this study was to assess the prevalence, cost, and outcomes of MDRO-BSI vs. non-MDRO-BSI among nursing home residents. DESIGN: Retrospective cohort study. SETTING: 960 bed tertiary academic medical center. PATIENTS: Persons ≥18 years old admitted to an acute care tertiary hospital from Skilled Nursing Facilities with a diagnosis of sepsis between 2015 and 2018. INTERVENTIONS: Retrospective analysis of prevalence and outcomes. MEASUREMENTS AND MAIN RESULTS: Among patients admitted to the study hospital with a diagnosis of sepsis during the study period, 7% were from nursing homes. The prevalence of MDRO-BSI was 47%. We identified 54 (50%) gram positive BSIs, 48 (45%) gram negative BSI and 5 (5%) fungal BSI. Thirty-one (57%) of the gram-positive infections and 14 (30%) of the gram-negative infections were with MDROs. The prevalence of BSI organisms were Staphylococcus aureus in 24%, Escherichia coli in 14%, Proteus mirabilis in 13%, Staphylococcus epidermidis in 8%, Enterococcus faecalis in 7%, and Klebsiella pneumoniae in 6%. We found that intensive care unit length of stay (7 days vs 5 days, P = .009), direct cost ($13,639 vs $9,922, P = .027), and total cost ($23,752 vs $17,900 P = .032) were significantly higher in patients with MDRO-BSI vs. non-MDRO-BSI. Patients with MDRO-BSI were twice as likely to receive inappropriate empiric antiinfective therapy (31% vs 16%, P = .006) and were more likely to die (49.1% vs 29.6%, P = .049). CONCLUSION: Nursing home residents have a high prevalence of MDRO-BSI, which is associated with higher risk of receiving inappropriate initial anti-infective therapy, higher cost, higher ICU LOS, and higher mortality. Our research adds new information about the prevalence of fungemia in this population.
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Infecção Hospitalar , Sepse , Adolescente , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana Múltipla , Hospitais , Humanos , Casas de Saúde , Prevalência , Estudos RetrospectivosRESUMO
This letter describes a focused, multi-dimensional optimization campaign around BL-1249, a fenamate class non-steroidal anti-inflammatory and a known activator of the K2P potassium channels TREK-1 (K2P2.1) and TREK-2 (K2P10.1). While BL-1249 has been widely profiled in vitro as a dual TREK-1/2 activator, poor physicochemical and DMPK properties have precluded a deeper understanding of the therapeutic potential of these key K2P channels across a broad spectrum of peripheral and central human disease. Here, we report multi-dimensional SAR that led to a novel TREK-1/2 dual activator chemotype, exemplified by ONO-2960632/VU6011992, with improved DMPK properties, representing a new lead for further optimization towards robust in vivo tool compounds.
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Canais de Potássio de Domínios Poros em Tandem/metabolismo , Tetra-Hidronaftalenos/uso terapêutico , Tetrazóis/uso terapêutico , Humanos , Tetra-Hidronaftalenos/farmacologia , Tetrazóis/farmacologiaRESUMO
To investigate the cellular distribution of tumor-promoting vs. non-tumor-promoting bryostatin analogues, we synthesized fluorescently labeled variants of two bryostatin derivatives that have previously shown either phorbol ester-like or bryostatin-like biological activity in U937 leukemia cells. These new fluorescent analogues both displayed high affinity for protein kinaseâ C (PKC) binding and retained the basic properties of the parent unlabeled compounds in U937 assays. The fluorescent compounds showed similar patterns of intracellular distribution in cells, however; this argues against an existing hypothesis that various patterns of intracellular distribution are responsible for differences in biological activity. Upon further characterization, the fluorescent compounds revealed a slow rate of cellular uptake; correspondingly, they showed reduced activity for cellular responses that were only transient upon treatment with phorbol ester or bryostatinâ 1.
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Briostatinas/química , Corantes Fluorescentes/química , Humanos , Ésteres de Forbol/química , Ligação Proteica , Proteína Quinase C/metabolismo , Células U937RESUMO
Cocaine use disorder (CUD) remains a debilitating health problem in the United States for which there are no Food and Drug Administration-approved treatment options. Accumulating anatomical and electrophysiological evidence indicates that the muscarinic acetylcholine receptor (mAChR) subtype 5 (M5 ) plays a critical role in the regulation of the mesolimbic dopaminergic reward circuitry, a major site of action for cocaine and other psychostimulants. In addition, M5 knockout mice exhibit reduced cocaine self-administration behaviors with no differences in sugar pellet-maintained responding relative to wild-type mice. These findings suggest that selective inhibition of M5 mAChR may provide a novel pharmacological approach for targeting CUD. Recently, we reported the synthesis and characterization of ML375, a selective negative allosteric modulator (NAM) for the rat and human M5 mAChR with optimized pharmacokinetic properties for systemic dosing in rodents. In the present study, male Sprague-Dawley rats were trained to self-administer intravenous cocaine (0.1-0.75 mg/kg/infusion) under a 10-response fixed ratio or a progressive ratio schedule of reinforcement. Under both schedules of reinforcement, ML375 produced dose-related reductions in cocaine self-administration. ML375 also modestly reduced sugar pellet-maintained responding on the 10-response, fixed ratio schedule but had no effect under a progressive ratio schedule of reinforcement. Further, ML375 did not affect general motor output as assessed by a rotarod test. Collectively, these results provide the first demonstration that selective inhibition of M5 using the M5 NAM ML375 can attenuate both the reinforcing effects and the relative strength of cocaine and suggest that M5 NAMs may represent a promising, novel treatment approach for CUD.
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Transtornos Relacionados ao Uso de Cocaína/prevenção & controle , Cocaína/administração & dosagem , Receptor Muscarínico M5/antagonistas & inibidores , Animais , Comportamento Animal/efeitos dos fármacos , Condicionamento Operante , Modelos Animais de Doenças , Inibidores da Captação de Dopamina/administração & dosagem , Relação Dose-Resposta a Droga , Masculino , Camundongos , Ratos , Ratos Sprague-Dawley , Esquema de Reforço , Recompensa , AutoadministraçãoRESUMO
This letter describes the continued optimization of M5 NAM ML375 (VU0483253). While a valuable in vivo tool compound, ML375has an excessively long elimination half-life in rat (t1/2=80h), which can be problematic in certain rodent addiction paradigms (e.g., reinstatement). Thus, we required an M5 NAM of comparable potency to ML375, but with a rat t1/2 of less than 4h. Steep SAR plagued this chemotype, and here we detail aniline replacements that offered some improvements over ML375, but failed to advance. Ultimately, incorporation of a single methyl group to the 9b-phenyl ring acted as a metabolic shunt, providing (S)-11 (VU6008667), an equipotent M5 NAM, with high CNS penetration, excellent selectivity versus M1-4 and the desired short half-life (t1/2=2.3h) in rat.
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Sistema Nervoso Central/metabolismo , Antagonistas Muscarínicos/farmacologia , Receptor Muscarínico M5/efeitos dos fármacos , Animais , Meia-Vida , Antagonistas Muscarínicos/farmacocinética , RatosRESUMO
Bryostatin 1, a complex macrocyclic lactone, is the subject of multiple clinical trials for cancer chemotherapy. Although bryostatin 1 biochemically functions like the classic mouse skin tumor promoter phorbol 12-myristate 13-acetate (PMA) to bind to and activate protein kinase C, paradoxically, it fails to induce many of the typical phorbol ester responses, including tumor promotion. Intense synthetic efforts are currently underway to develop simplified bryostatin analogs that preserve the critical functional features of bryostatin 1, including its lack of tumor promoting activity. The degree to which bryostatin analogs maintain the unique pattern of biological behavior of bryostatin 1 depends on the specific cellular system and the specific response. Merle 23 is a significantly simplified bryostatin analog that retains bryostatin like activity only to a limited extent. Here, we show that in mouse epidermal cells the activity of Merle 23 was either similar to bryostatin 1 or intermediate between bryostatin 1 and PMA, depending on the specific parameter examined. We then examined the hyperplastic and tumor promoting activity of Merle 23 on mouse skin. Merle 23 showed substantially reduced hyperplasia and was not tumor promoting at a dose comparable to that for PMA. These results suggest that there may be substantial flexibility in the design of bryostatin analogs that retain its lack of tumor promoting activity. © 2016 Wiley Periodicals, Inc.
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Antineoplásicos/farmacologia , Briostatinas/farmacologia , Queratinócitos/efeitos dos fármacos , Neoplasias Cutâneas/induzido quimicamente , Neoplasias Cutâneas/tratamento farmacológico , Animais , Desenho de Fármacos , Epiderme/efeitos dos fármacos , Epiderme/metabolismo , Epiderme/patologia , Feminino , Queratinócitos/metabolismo , Queratinócitos/patologia , Camundongos Endogâmicos BALB C , Camundongos Endogâmicos SENCAR , Ésteres de Forbol/farmacologia , Proteína Quinase C/metabolismo , Neoplasias Cutâneas/metabolismo , Neoplasias Cutâneas/patologiaRESUMO
As an initial step in designing a simplified bryostatin hybrid molecule, three bryostatin analogues bearing a diacylglycerol lactone-based C-ring, which possessed the requisite pharmacophores for binding to protein kinase C (PKC) together with a modified bryostatin-like A- and B-ring region, were synthesized and evaluated. Merle 46 and Merle 47 exhibited binding affinity to PKC alpha with Ki values of 7000 ± 990 and 4940 ± 470 nM, respectively. Reinstallation of the trans-olefin and gem-dimethyl group present in bryostatin 1 in Merle 48 resulted in improved binding affinity, 363 ± 42 nM. While Merle 46 and 47 were only marginally active biologically, Merle 48 showed sufficient activity on the U937 cells to confirm that it was PMA-like for growth and attachment, as predicted by the substitution pattern of its A- and B-rings.
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Briostatinas/síntese química , Briostatinas/farmacologia , Diglicerídeos/química , Lactonas/química , Briostatinas/metabolismo , Espectroscopia de Ressonância Magnética Nuclear de Carbono-13 , Proteína Quinase C/metabolismo , Espectroscopia de Prótons por Ressonância Magnética , Espectrometria de Massas por Ionização por Electrospray , Especificidade por SubstratoRESUMO
This Letter describes a ligand-based virtual screening campaign utilizing SAR data around the M5 NAMs, ML375 and VU6000181. Both QSAR and shape scores were employed to virtually screen a 98,000-member compound library. Neither approach alone proved productive, but a consensus score of the two models identified a novel scaffold which proved to be a modestly selective, but weak inhibitor (VU0549108) of the M5 mAChR (M5 IC50=6.2µM, M1-4 IC50s>10µM) based on an unusual 8-((1,3,5-trimethyl-1H-pyrazol-4-yl)sulfonyl)-1-oxa-4-thia-8-azaspiro[4,5]decane scaffold. [(3)H]-NMS binding studies showed that VU0549108 interacts with the orthosteric site (Ki of 2.7µM), but it is not clear if this is negative cooperativity or orthosteric binding. Interestingly, analogs synthesized around VU0549108 proved weak, and SAR was very steep. However, this campaign validated the approach and warranted further expansion to identify additional novel chemotypes.
Assuntos
Receptor Muscarínico M5/antagonistas & inibidores , Animais , Células CHO , Cricetulus , Descoberta de Drogas , Humanos , Ligantes , Antagonistas Muscarínicos/química , Antagonistas Muscarínicos/farmacologia , Relação Quantitativa Estrutura-AtividadeRESUMO
Previous research on inter-individual variation in the calls of corvids has largely been restricted to single call types, such as alarm or contact calls, and has rarely considered the effects of age on call structure. This study explores structural variation in a contextually diverse set of "caw" calls of the American crow (Corvus brachyrhynchos), including alarm, foraging recruitment and territorial calls, and searches for structural features that may be associated with behavioural context and caller sex, age, and identity. Automated pitch detection algorithms are used to generate 23 pitch-related and spectral parameters for a collection of caws from 18 wild, marked crows. Using principal component analysis and mixed models, we identify independent axes of acoustic variation associated with behavioural context and with caller sex, respectively. We also have moderate success predicting caller sex and identity from call structure. However, we do not find significant acoustic variation with respect to caller age.
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Listeners' use of social information during speech perception was investigated by measuring transcription accuracy of Chinese-accented speech in noise while listeners were presented with a congruent Chinese face, an incongruent Caucasian face, or an uninformative silhouette. When listeners were presented with a Chinese face they transcribed more accurately than when presented with the Caucasian face. This difference existed both for listeners with a relatively high level of experience and for listeners with a relatively low level of experience with Chinese-accented English. Overall, these results are inconsistent with a model of social speech perception in which listener bias reduces attendance to the acoustic signal. These results are generally consistent with exemplar models of socially indexed speech perception predicting that activation of a social category will raise base activation levels of socially appropriate episodic traces, but the similar performance of more and less experienced listeners suggests the need for a more nuanced view with a role for both detailed experience and listener stereotypes.
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Ruído , Percepção da Fala , Povo Asiático , China , Humanos , População BrancaRESUMO
INTRODUCTION: Despite the growing use of immune checkpoint inhibitors (ICI) in cancer treatment, data regarding ICI-associated pericardial disease are primarily derived from case reports and case series. ICI related pericardial disease can be difficult to diagnose and is associated with significant morbidity. We conducted a systematic review to further characterize the epidemiology, clinical presentation, and outcomes of this patient population. METHODS: A search of four databases resulted in 31 studies meeting inclusion criteria. Patients > 18 years old who presented with ICI mediated pericardial disease were included. Intervention was medical + surgical therapy and outcomes were development of cardiac tamponade, morbidity, and mortality. RESULTS: Thirty- eight patients across 31 cases were included. Patients were majority male (72%) with a median age of 63. Common symptoms included dyspnea (59%) and chest pain (32%), with 41% presenting with cardiac tamponade. Lung cancer (81%) was the most prevalent, and nivolumab (61%) and pembrolizumab (34%) were the most used ICIs. Pericardiocentesis was performed in 68% of patients, and 92% experienced symptom improvement upon ICI cessation. Overall mortality was 16%. DISCUSSION: This study provides the most comprehensive analysis of ICI-mediated pericardial disease to date. Patients affected were most commonly male with lung cancer treated with either Nivolumab or Pembrolizumab. Diagnosis may be challenging in the setting of occult presentation with normal EKG and physical exam as well as delayed onset from therapy initiation. ICI-associated pericardial disease demonstrates high morbidity and mortality, as evidenced by a majority of patients requiring pericardiocentesis.
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Molecular-glue degraders are small molecules that induce a specific interaction between an E3 ligase and a target protein, resulting in the target proteolysis. The discovery of molecular glue degraders currently relies mostly on screening approaches. Here, we describe screening of a library of cereblon (CRBN) ligands against a panel of patient-derived cancer cell lines, leading to the discovery of SJ7095, a potent degrader of CK1α, IKZF1 and IKZF3 proteins. Through a structure-informed exploration of structure activity relationship (SAR) around this small molecule we develop SJ3149, a selective and potent degrader of CK1α protein in vitro and in vivo. The structure of SJ3149 co-crystalized in complex with CK1α + CRBN + DDB1 provides a rationale for the improved degradation properties of this compound. In a panel of 115 cancer cell lines SJ3149 displays a broad antiproliferative activity profile, which shows statistically significant correlation with MDM2 inhibitor Nutlin-3a. These findings suggest potential utility of selective CK1α degraders for treatment of hematological cancers and solid tumors.
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Antineoplásicos , Neoplasias , Humanos , Antineoplásicos/farmacologia , Antineoplásicos/química , Linhagem Celular , Neoplasias/tratamento farmacológico , Proteólise , Ubiquitina-Proteína Ligases/genética , Ubiquitina-Proteína Ligases/metabolismoRESUMO
The perception of coarticulated speech as it unfolds over time was investigated by monitoring eye movements of participants as they listened to words with oral vowels or with late or early onset of anticipatory vowel nasalization. When listeners heard [CVNC] and had visual choices of images of CVNC (e.g., send) and CVC (said) words, they fixated more quickly and more often on the CVNC image when onset of nasalization began early in the vowel compared to when the coarticulatory information occurred later. Moreover, when a standard eye movement programming delay is factored in, fixations on the CVNC image began to occur before listeners heard the nasal consonant. Listeners' attention to coarticulatory cues for velum lowering was selective in two respects: (a) listeners assigned greater perceptual weight to coarticulatory information in phonetic contexts in which [V] but not N is an especially robust property, and (b) individual listeners differed in their perceptual weights. Overall, the time course of perception of velum lowering in American English indicates that the dynamics of perception parallel the dynamics of the gestural information encoded in the acoustic signal. In real-time processing, listeners closely track unfolding coarticulatory information in ways that speed lexical activation.
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Acústica da Fala , Percepção da Fala , Estimulação Acústica , Audiometria da Fala , Sinais (Psicologia) , Movimentos Oculares , Humanos , Modelos Lineares , Estimulação Luminosa , Psicoacústica , Tempo de Reação , Detecção de Sinal Psicológico , Espectrografia do Som , Fatores de Tempo , Percepção VisualRESUMO
Germline adenomatous polyposis coli (APC) mutation in patients with familial adenomatous polyposis (FAP) promotes gastrointestinal polyposis, including the formation of frequent gastric fundic gland polyps (FGPs). In this study, we investigated how dysregulated Wnt signaling promotes FGPs and why they localize to the corpus region of the stomach. We developed a biobank of FGP and surrounding nonpolyp corpus biopsies and organoids from patients with FAP for comparative studies. Polyp biopsies and polyp-derived organoids exhibited enhanced Wnt target gene expression. Polyp-derived organoids with intrinsically upregulated Wnt signaling showed poor tolerance to further induction, suggesting that high Wnt restricts growth. Targeted genomic sequencing revealed that most gastric polyps did not arise via APC loss of heterozygosity. Studies in genetic mouse models demonstrated that heterozygous Apc loss increased epithelial cell proliferation in the corpus but not the antrum, while homozygous Apc loss was not maintained in the corpus yet induced hyperproliferation in the antrum. Our findings suggest that heterozygous APC mutation in patients with FAP may be sufficient to drive polyp formation in the corpus region while subsequent loss of heterozygosity to further enhance Wnt signaling is not tolerated. This finding contextualizes the abundant yet benign nature of gastric polyps in FAP patient corpus compared with the rare, yet adenomatous polyps in the antrum.
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Polipose Adenomatosa do Colo , Pólipos Adenomatosos , Humanos , Animais , Camundongos , Via de Sinalização Wnt , Polipose Adenomatosa do Colo/genética , Polipose Adenomatosa do Colo/patologiaRESUMO
Thalidomide and its analogues are frequently used in PROTAC design. However, they are known to be inherently unstable, undergoing hydrolysis even in commonly utilized cell culture media. We recently reported that phenyl glutarimide (PG)-based PROTACs displayed improved chemical stability and, consequently, improved protein degradation efficacy and cellular potency. Our optimization efforts, aiming to further improve the chemical stability and eliminate the racemization-prone chiral center in PG, led us to the development of phenyl dihydrouracil (PD)-based PROTACs. Here we describe the design and synthesis of LCK-directing PD-PROTACs and compare their physicochemical and pharmacological properties to those of the corresponding IMiD and PG analogues.
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Synthesis, characterization, and catalytic alkyne polymerization results for the first trianionic pincer alkylidyne complex, [(t)BuOCO]W≡CC(CH(3))(3)(THF)(2) (6), are described. Complex 6 is a highly active catalyst for the polymerization of acetylenes and exhibits a high turnover number (4371), activity (1.05 × 10(6) g(PPA) mol(cat)(-1) h(-1)),and yield (87%) for the polymerization of 1-ethynyl-4-fluorobenzene.
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The worldwide coronavirus disease 2019 pandemic has had devastating effects on health, healthcare infrastructure, social structure, and economics. One of the limiting factors in containing the spread of this virus has been the lack of widespread availability of fast, inexpensive, and reliable methods for testing of individuals. Frequent screening for infected and often asymptomatic people is a cornerstone of pandemic management plans. Here, we introduce 2 pH-sensitive "LAMPshade" dyes as novel readouts in an isothermal Reverse Transcriptase Loop-mediated isothermal AMPlification amplification assay for severe acute respiratory syndrome coronavirus 2 RNA. The resulting JaneliaLAMP assay is robust, simple, inexpensive, and has low technical requirements, and we describe its use and performance in direct testing of contrived and clinical samples without RNA extraction.