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OBJECTIVES: Cognitive impairment, anxiety, depression, fatigue, and dependence in instrumental activities of daily living (ADL) are common after stroke; however, little is known about how these outcomes may differ following treatment with endovascular clot retrieval (ECR), intravenous tissue plasminogen activator (t-PA), or conservative management. METHODS: Patients were recruited after acute treatment and invited to participate in an outcome assessment 90-120 days post-stroke. The assessment included a cognitive test battery and several questionnaires. The COVID-19 pandemic led to significant disruptions in recruitment and data collection, and the t-PA and conservative management groups were combined into a standard medical care (SMC) group. RESULTS: Sixty-two participants were included in the study (ECR = 31, SMC = 31). Mean age was 66.5 (20-86) years, and 35 (56.5%) participants were male. Participants treated with ECR had significantly higher National Institutes of Health Stroke Scale scores at presentation and significantly lower education. After adjusting for stroke severity, premorbid intellectual ability, and age, treatment with ECR was associated with significantly better performances on measures of cognitive screening, visual working memory, and verbal learning and memory. Participants treated with ECR also experienced less fatigue and were more likely to achieve independence in basic and instrumental ADLs. Despite this, cognitive impairment and fatigue were still common among participants treated with ECR and anxiety and depression symptoms were experienced similarly by both groups. CONCLUSIONS: Cognitive impairment and fatigue were less common but still prevalent following treatment with ECR. This has important practical implications for stroke rehabilitation, and routine assessment of cognition, emotion, and fatigue is recommended for all stroke survivors regardless of stroke treatment and functional outcome.
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Alzheimer's disease (AD) is the leading cause of dementia in older adults. Although AD progression is characterized by stereotyped accumulation of proteinopathies, the affected cellular populations remain understudied. Here we use multiomics, spatial genomics and reference atlases from the BRAIN Initiative to study middle temporal gyrus cell types in 84 donors with varying AD pathologies. This cohort includes 33 male donors and 51 female donors, with an average age at time of death of 88 years. We used quantitative neuropathology to place donors along a disease pseudoprogression score. Pseudoprogression analysis revealed two disease phases: an early phase with a slow increase in pathology, presence of inflammatory microglia, reactive astrocytes, loss of somatostatin+ inhibitory neurons, and a remyelination response by oligodendrocyte precursor cells; and a later phase with exponential increase in pathology, loss of excitatory neurons and Pvalb+ and Vip+ inhibitory neuron subtypes. These findings were replicated in other major AD studies.
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ABSTRACT: Gene therapy for severe hemophilia A uses an adeno-associated virus (AAV) vector and liver-specific promoters that depend on healthy hepatocyte function to achieve safe and long-lasting increases in factor VIII (FVIII) activity. Thus, hepatocyte health is an essential aspect of safe and successful gene therapy. Many people living with hemophilia A have current or past chronic hepatitis C virus infection, metabolic dysfunction-associated steatosis or steatohepatitis, or other conditions that may compromise the efficacy and safety of AAV-mediated gene therapy. In addition, gene therapy may induce an immune response to transduced hepatocytes, leading to liver inflammation and reduced FVIII activity. The immune response can be treated with immunosuppression, but close monitoring of liver function tests and factor levels is necessary. The long-term risk of hepatocellular carcinoma associated with gene therapy is unknown. Routine screening by imaging for hepatocellular carcinoma, preferable every 6 months, is essential in patients at high risk and recommended in all recipients of hemophilia A gene therapy. This paper describes our current understanding of the biologic underpinnings of how liver health affects hemophilia A gene therapy, and provides practical clinical guidance for assessing, monitoring, and managing liver health both before and after gene therapy.
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Terapia Genética , Hemofilia A , Fígado , Hemofilia A/terapia , Hemofilia A/genética , Humanos , Terapia Genética/métodos , Fígado/metabolismo , Fígado/patologia , Dependovirus/genética , Vetores Genéticos , Fator VIII/genéticaRESUMO
BACKGROUND AND OBJECTIVE: Autoimmune encephalitis (AE) is often associated with clinically significant memory impairment. This study aimed to evaluate memory in a cross-sectional prospective AE cohort using multiple memory paradigms. METHODS: 52 patients (50% seropositive) meeting Graus criteria for possible AE were prospectively recruited between October 2019 and August 202. A comprehensive examination of memory was performed, including tests of supraspan verbal memory (list learning), logicosemantic memory (story learning), figural memory (learning of geometric designs), and verbal associative learning (verbal paired associates). Memory scores were compared to demographically adjusted normative data. Pattern analysis was conducted to assist in the identification of patterns in memory performances. RESULTS: Mean memory scores were not significantly below the normative mean. At an individual patient level, over 20% of the cohort exhibited impaired delayed figural memory, supraspan verbal memory learning and recall. Observed performances were significantly below expected performance for story learning (p = 0.017) and recall (p = 0.003), figural recall (p < 0.0001), initial acquisition (p < 0.001) and final acquisition of a list (p < 0.001) and all delayed recall measures of the list (p < 0.00001). 54.76% of patients exhibited intact psychometrics, and 16 distinct patterns of impairment emerged, indicating variability in memory outcomes. DISCUSSION: While statistical evidence for memory impairment did not emerge at an aggregate level, a proportion of patients present with evidence of abnormal memory performance on psychometrics. Variability in impaired memory measures argues for an individualised patient-focused approach to clinical assessment in AE. Future research should validate these findings with a larger sample size and explore the relationships between memory profiles and other cognitive functions.
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Encefalite , Transtornos da Memória , Humanos , Estudos Transversais , Feminino , Masculino , Pessoa de Meia-Idade , Adulto , Estudos Prospectivos , Encefalite/fisiopatologia , Encefalite/imunologia , Encefalite/complicações , Transtornos da Memória/etiologia , Transtornos da Memória/fisiopatologia , Idoso , Testes Neuropsicológicos , Doença de Hashimoto/fisiopatologia , Doença de Hashimoto/complicações , Memória/fisiologia , Adulto JovemRESUMO
Gene transfer therapies utilizing adeno-associated virus (AAV) vectors involve a complex drug design with multiple components that may impact immunogenicity. Valoctocogene roxaparvovec is an AAV serotype 5 (AAV5)-vectored gene therapy for the treatment of hemophilia A that encodes a B-domain-deleted human factor VIII (FVIII) protein controlled by a hepatocyte-selective promoter. Following previous results from the first-in-human phase 1/2 clinical trial, we assessed AAV5-capsid- and transgene-derived FVIII-specific immune responses with 2 years of follow-up data from GENEr8-1, a phase 3, single-arm, open-label study in 134 adult men with severe hemophilia A. No FVIII inhibitors were detected following administration of valoctocogene roxaparvovec. Immune responses were predominantly directed toward the AAV5 capsid, with all participants developing durable anti-AAV5 antibodies. Cellular immune responses specific for the AAV5 capsid were detected in most participants by interferon-γ enzyme-linked immunosorbent spot assay 2 weeks following dose administration and declined or reverted to negative over the first 52 weeks. These responses were weakly correlated with alanine aminotransferase elevations and showed no association with changes in FVIII activity. FVIII-specific cellular immune responses were less frequent and more sporadic compared with those specific for AAV5 and showed no association with safety or efficacy parameters.
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Dependovirus , Fator VIII , Terapia Genética , Vetores Genéticos , Hemofilia A , Humanos , Hemofilia A/terapia , Hemofilia A/imunologia , Hemofilia A/genética , Dependovirus/genética , Dependovirus/imunologia , Terapia Genética/métodos , Vetores Genéticos/genética , Vetores Genéticos/administração & dosagem , Fator VIII/genética , Fator VIII/imunologia , Masculino , Adulto , Resultado do Tratamento , Transgenes , Adulto Jovem , Anticorpos Antivirais/imunologia , Anticorpos Antivirais/sangue , Pessoa de Meia-IdadeRESUMO
Many tumor types harbor alterations in the Hippo pathway, including mesothelioma, where a high percentage of cases are considered YAP1/TEAD dependent. Identification of autopalmitoylation sites in the hydrophobic palmitate pocket of TEADs, which may be necessary for YAP1 protein interactions, has enabled modern drug discovery platforms to generate compounds that allosterically inhibit YAP1/TEAD complex formation and transcriptional activity. We report the discovery and characterization of a novel YAP1/TEAD inhibitor MRK-A from an aryl ether chemical series demonstrating potent and specific inhibition of YAP1/TEAD activity. In vivo, MRK-A showed a favorable tolerability profile in mice and demonstrated pharmacokinetics suitable for twice daily oral dosing in preclinical efficacy studies. Importantly, monotherapeutic targeting of YAP1/TEAD in preclinical models generated regressions in a mesothelioma CDX model; however, rapid resistance to therapy was observed. RNA-sequencing of resistant tumors revealed mRNA expression changes correlated with the resistance state and a marked increase of hepatocyte growth factor (HGF) expression. In vitro, exogenous HGF was able to fully rescue cytostasis induced by MRK-A in mesothelioma cell lines. In addition, co-administration of small molecule inhibitors of the MET receptor tyrosine kinase suppressed the resistance generating effect of HGF on MRK-A induced growth inhibition. In this work, we report the structure and characterization of MRK-A, demonstrating potent and specific inhibition of YAP1/TAZ-TEAD-mediated transcriptional responses, with potential implications for treating malignancies driven by altered Hippo signaling, including factors resulting in acquired drug resistance.
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Proteínas Adaptadoras de Transdução de Sinal , Resistencia a Medicamentos Antineoplásicos , Fator de Crescimento de Hepatócito , Proteínas Proto-Oncogênicas c-met , Transdução de Sinais , Fatores de Transcrição , Proteínas de Sinalização YAP , Humanos , Fator de Crescimento de Hepatócito/metabolismo , Animais , Fatores de Transcrição/metabolismo , Fatores de Transcrição/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/antagonistas & inibidores , Proteínas Proto-Oncogênicas c-met/metabolismo , Camundongos , Transdução de Sinais/efeitos dos fármacos , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/antagonistas & inibidores , Resistencia a Medicamentos Antineoplásicos/efeitos dos fármacos , Linhagem Celular Tumoral , Ensaios Antitumorais Modelo de Xenoenxerto , Bibliotecas de Moléculas Pequenas/farmacologia , Fatores de Transcrição de Domínio TEA , Proliferação de Células/efeitos dos fármacosRESUMO
Background Little is known regarding cognitive outcomes following treatment with endovascular clot retrieval (ECR) and intravenous tissue plasminogen activator (t-PA). We aimed to determine if there were any differences on a measure of cognitive screening between patients treated with ECR, t-PA, and those who were managed conservatively. Methods The medical records of ischaemic stroke patients admitted to Monash Medical Centre between January 2019 and December 2019 were retrospectively reviewed. Information extracted from medical records included age, sex, National Institutes of Health Stroke Scale at presentation, location of occlusion, treatment type, medical history, and cognitive screening performance measured by the Montreal Cognitive Assessment (MoCA). Results Eighty-two patients met the inclusion criteria (mean age = 66.5 ± 13.9; 49 male, 33 female). Patients treated with ECR performed significantly better on the MoCA (n = 36, 24.1 ± 4.3) compared to those who were managed conservatively (n = 26, 20.7 ± 5.5). Performance for patients treated with t-PA (n = 20, 23.9 ± 3.5) fell between the ECR and conservative management groups, but they did not significantly differ from either. Conclusion Our retrospective chart review found that ischaemic stroke patients treated with ECR appear to perform better on cognitive screening compared to patients who are managed conservatively. We also found that patients treated with ECR and t-PA appear to have similar cognitive screening performances in the acute stages following ischaemic stroke, although this finding is likely to have been impacted by group differences in stroke characteristics and may reflect the possibility that the ECR group performed better than expected based on their stroke severity.
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Isquemia Encefálica , AVC Isquêmico , Acidente Vascular Cerebral , Trombose , Humanos , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Ativador de Plasminogênio Tecidual/uso terapêutico , Acidente Vascular Cerebral/tratamento farmacológico , Isquemia Encefálica/tratamento farmacológico , Fibrinolíticos/uso terapêutico , Estudos Retrospectivos , AVC Isquêmico/tratamento farmacológico , Trombose/tratamento farmacológico , Terapia Trombolítica/métodos , CogniçãoRESUMO
Recombinant adeno-associated virus (AAV) vectors are the leading delivery vehicle used for in vivo gene therapies. Anti-AAV antibodies (AAV Abs) can interact with the viral capsid component of an AAV-based gene therapy (GT). Therefore, patients with preexisting AAV Abs (seropositive patients) are often excluded from GT trials to prevent treatment of patients who are unlikely to benefit1 or may have a higher risk for adverse events outweighing treatment benefits. On the contrary, unnecessary exclusion of patients with high unmet medical need should be avoided. Instead, a risk-benefit assessment that weighs the potential risks due to seropositivity vs. severity of disease and available treatment options, should drive the decision if patient selection is required. Assays for patient selection must be validated according to their intended use following national regulations/standards for diagnostic assays in appropriate laboratories. In this review, we summarize the current process of patient selection, including assay cutoff criteria and related assay validation approaches. We further provide considerations on regulatory requirements for the development of in vitro diagnostic tests supporting market authorization of a corresponding GT.
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BACKGROUND AND OBJECTIVE: Autoimmune encephalitis (AE) is a rare neuroinflammatory disease affecting the central nervous system. To examine language functions in patients with different subsets of AE consisting of seropositive and seronegative groups. METHODS: Fifty-two patients were recruited from neurology departments in Melbourne, Australia, who met clinical criteria for possible AE. Language tests include the Naming Test from the Sydney Language Battery (SydBat), the semantic fluency trial from the Controlled Oral Word Association Test (COWAT), and the Vocabulary and Similarities subtests of the Weschler Abbreviated Scale of Intelligence-Second Edition. The results were standardised with normative data. RESULTS: The mean age of our cohort was 52.5 years old, with the average time from hospital admission to recruitment being 38.41 months. At an aggregate level, none of the mean language test z-scores were below normative data. At the patient level, impairment rates were 18.37% for COWAT (animals), 28.57% for SydBat (naming), 4.65% for Similarities, and 4.55% for Vocabulary. Chi-squared goodness of fit tests indicated that observed performances were significantly below expected performances for the SydBat (naming) test (p < 0.0001) and COWAT (animals) (p = 0.004). DISCUSSION: While, on average, language functions were within normal limits in patients with AE, but a subgroup exhibited lower performance in semantic fluency and visual confrontation naming, with impairment rates below expected norms. To advance understanding of language in chronic AE patients, exploring the impact of seizure burden, antiseizure medication use, and the relationship of language functions with other cognitive functions is crucial.
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Encefalite , Transtornos da Linguagem , Humanos , Feminino , Masculino , Pessoa de Meia-Idade , Encefalite/diagnóstico , Encefalite/complicações , Encefalite/sangue , Encefalite/imunologia , Transtornos da Linguagem/etiologia , Transtornos da Linguagem/diagnóstico , Adulto , Idoso , Testes de Linguagem , Doença de Hashimoto/diagnóstico , Doença de Hashimoto/complicações , Doença de Hashimoto/sangue , Estudos de CoortesRESUMO
OBJECTIVE: This study uses the Wechsler intelligence and memory scales to characterize the cognitive function of patients with autoimmune encephalitis (AE) in the chronic stage of the disease. AE is a group of neuroinflammatory disorders, and cognitive impairment is a significant source of chronic morbidity in these patients. METHODS: Fifty patients with an average disease duration of 3.2 years after diagnosis were prospectively recruited from four hospitals. They underwent a comprehensive cognitive examination using the Wechsler Abbreviated Scale of Intelligence (WASI-II), Wechsler Adult Intelligence Scale (WAIS-IV) and Wechsler Memory Scale (WMS-IV). Summary statistics were computed, and single-sample and independent-samples t tests were used to compare the cohort to normative data. RESULTS: The results revealed significantly reduced performances in perceptual reasoning, processing speed, and working memory among AE patients. Seropositive AE patients exhibited below-norm processing speed, while the seronegative group showed reduced working memory and processing speed. Delayed memory performance was significantly below expectations only in seronegative patients. Pattern analysis indicated that intact cognition was the most observed outcome after AE, but significant heterogeneity was observed among the impaired patients. CONCLUSIONS: The study identified deficits in perceptual reasoning, processing speed, and working memory among chronic AE patients. Pattern analysis highlighted positive long-term cognitive outcomes for many but varied outcomes for those with ongoing difficulties. Although severely cognitively impaired patients were not included, the findings apply to AE cohorts who attend outpatient clinical neuropsychology consultations emphasizing the need for thorough cognitive assessment. The results suggest a need for further research targeting other cognitive domains, including executive functions.
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Doenças Autoimunes do Sistema Nervoso , Cognição , Adulto , Humanos , Estudos Prospectivos , Testes Neuropsicológicos , Austrália , Memória de Curto PrazoRESUMO
Adeno-associated virus gene therapy has been the subject of intensive investigation for monogenic disease gene addition therapy for more than 25 years, yet few therapies have been approved by regulatory agencies. Most have not progressed beyond phase 1/2 due to toxicity, lack of efficacy, or both. The liver is a natural target for adeno-associated virus since most serotypes have a high degree of tropism for hepatocytes due to cell surface receptors for the virus and the unique liver sinusoidal geometry facilitating high volumes of blood contact with hepatocyte cell surfaces. Recessive monogenic diseases such as hemophilia represent promising targets since the defective proteins are often synthesized in the liver and secreted into the circulation, making them easy to measure, and many do not require precise regulation. Yet, despite initiation of many disease-specific clinical trials, therapeutic windows are often nonexistent, resulting in excess toxicity and insufficient efficacy. Iterative progress built on these attempts is best illustrated by hemophilia, with the first regulatory approvals for factor IX and factor VIII gene therapies eventually achieved 25 years after the first gene therapy studies in humans. Although successful gene transfer may result in the production of sufficient transgenic protein to modify the disease, many emerging questions on durability, predictability, reliability, and variability of response have not been answered. The underlying biology accounting for these heterogeneous responses and the interplay between host and virus is the subject of intense investigation and the subject of this review.
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Dependovirus , Terapia Genética , Vetores Genéticos , Hemofilia A , Fígado , Humanos , Dependovirus/genética , Hemofilia A/terapia , Hemofilia A/genética , Terapia Genética/métodos , Fígado/metabolismo , Fígado/virologia , Animais , Fator VIII/genética , Fator VIII/metabolismo , Técnicas de Transferência de GenesRESUMO
Replication-incompetent adeno-associated virus (AAV)-based vectors are nonpathogenic viral particles used to deliver therapeutic genes to treat multiple monogenic disorders. AAVs can elicit immune responses; thus, one challenge in AAV-based gene therapy is the presence of neutralizing antibodies against vector capsids that may prevent transduction of target cells or elicit adverse findings. We present safety findings from two 12-week studies in nonhuman primates (NHPs) with pre-existing or treatment-emergent antibodies. In the first study, NHPs with varying levels of naturally acquired anti-AAV5 antibodies were dosed with an AAV5-based vector encoding human factor VIII (hFVIII). In the second study, NHPs with no pre-existing anti-AAV antibodies were dosed with an AAV5-based vector carrying the beta subunit of choriogonadotropic hormone (bCG); this led to the induction of high-titer antibodies against the AAV5 capsid. Four weeks later, the same NHPs received an equivalent dose of an AAV5-based vector carrying human factor IX (hFIX). In both of these studies, the administration of vectors carrying hFVIII, bCG, and hFIX was well-tolerated in NHPs with no adverse clinical pathology or microscopic findings. These two studies demonstrate the safety of AAV-based vector administration in NHPs with either low-titer pre-existing anti-AAV5 antibodies or re-administration, even in the presence of high-titer antibodies.
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Capsídeo , Dependovirus , Animais , Humanos , Dependovirus/genética , Anticorpos Neutralizantes/genética , Terapia GenéticaRESUMO
The cognitive abilities of humans are distinctive among primates, but their molecular and cellular substrates are poorly understood. We used comparative single-nucleus transcriptomics to analyze samples of the middle temporal gyrus (MTG) from adult humans, chimpanzees, gorillas, rhesus macaques, and common marmosets to understand human-specific features of the neocortex. Human, chimpanzee, and gorilla MTG showed highly similar cell-type composition and laminar organization as well as a large shift in proportions of deep-layer intratelencephalic-projecting neurons compared with macaque and marmoset MTG. Microglia, astrocytes, and oligodendrocytes had more-divergent expression across species compared with neurons or oligodendrocyte precursor cells, and neuronal expression diverged more rapidly on the human lineage. Only a few hundred genes showed human-specific patterning, suggesting that relatively few cellular and molecular changes distinctively define adult human cortical structure.
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Cognição , Hominidae , Neocórtex , Lobo Temporal , Animais , Humanos , Perfilação da Expressão Gênica , Gorilla gorilla/genética , Hominidae/genética , Hominidae/fisiologia , Macaca mulatta/genética , Pan troglodytes/genética , Filogenia , Transcriptoma , Neocórtex/fisiologia , Especificidade da Espécie , Lobo Temporal/fisiologiaRESUMO
Variation in cytoarchitecture is the basis for the histological definition of cortical areas. We used single cell transcriptomics and performed cellular characterization of the human cortex to better understand cortical areal specialization. Single-nucleus RNA-sequencing of 8 areas spanning cortical structural variation showed a highly consistent cellular makeup for 24 cell subclasses. However, proportions of excitatory neuron subclasses varied substantially, likely reflecting differences in connectivity across primary sensorimotor and association cortices. Laminar organization of astrocytes and oligodendrocytes also differed across areas. Primary visual cortex showed characteristic organization with major changes in the excitatory to inhibitory neuron ratio, expansion of layer 4 excitatory neurons, and specialized inhibitory neurons. These results lay the groundwork for a refined cellular and molecular characterization of human cortical cytoarchitecture and areal specialization.
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Neocórtex , Humanos , Neocórtex/metabolismo , Neocórtex/ultraestrutura , Neurônios/classificação , Neurônios/metabolismo , Transcriptoma , Análise da Expressão Gênica de Célula Única , FilogeniaRESUMO
Neocortical layer 1 (L1) is a site of convergence between pyramidal-neuron dendrites and feedback axons where local inhibitory signaling can profoundly shape cortical processing. Evolutionary expansion of human neocortex is marked by distinctive pyramidal neurons with extensive L1 branching, but whether L1 interneurons are similarly diverse is underexplored. Using Patch-seq recordings from human neurosurgical tissue, we identified four transcriptomic subclasses with mouse L1 homologs, along with distinct subtypes and types unmatched in mouse L1. Subclass and subtype comparisons showed stronger transcriptomic differences in human L1 and were correlated with strong morphoelectric variability along dimensions distinct from mouse L1 variability. Accompanied by greater layer thickness and other cytoarchitecture changes, these findings suggest that L1 has diverged in evolution, reflecting the demands of regulating the expanded human neocortical circuit.
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Neocórtex , Animais , Humanos , Camundongos , Axônios/metabolismo , Interneurônios/metabolismo , Neocórtex/citologia , Neocórtex/metabolismo , Células Piramidais/metabolismo , TranscriptomaRESUMO
Human cortex transcriptomic studies have revealed a hierarchical organization of γ-aminobutyric acid-producing (GABAergic) neurons from subclasses to a high diversity of more granular types. Rapid GABAergic neuron viral genetic labeling plus Patch-seq (patch-clamp electrophysiology plus single-cell RNA sequencing) sampling in human brain slices was used to reliably target and analyze GABAergic neuron subclasses and individual transcriptomic types. This characterization elucidated transitions between PVALB and SST subclasses, revealed morphological heterogeneity within an abundant transcriptomic type, identified multiple spatially distinct types of the primate-specialized double bouquet cells (DBCs), and shed light on cellular differences between homologous mouse and human neocortical GABAergic neuron types. These results highlight the importance of multimodal phenotypic characterization for refinement of emerging transcriptomic cell type taxonomies and for understanding conserved and specialized cellular properties of human brain cell types.
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Neurônios GABAérgicos , Interneurônios , Neocórtex , Animais , Humanos , Camundongos , Fenômenos Eletrofisiológicos , Neurônios GABAérgicos/metabolismo , Ácido gama-Aminobutírico/metabolismo , Interneurônios/metabolismo , Neocórtex/citologia , Neocórtex/metabolismo , Técnicas de Patch-ClampRESUMO
The pursuit of a trivalent plutonium halide phosphine oxide compound, e.g., "PuBr3(OPR)3," instead led to the isolation of the tetravalent trans-PuIVBr4(OPCy3)2, PuBr/Cy, compound by spontaneous oxidation of PuIII. The donating nature of phosphine oxides has allowed the isolation and characterization of PuBr/Cy by crystallographic, multinuclear NMR, solid state, and solution phase UV-vis-NIR spectroscopic techniques. The presence of a putative plutonyl(VI) complex formulated as "trans-PuVIO2Br2(OPCy3)2" was also observed spectroscopically and tentatively by single-crystal X-ray diffraction as a cocrystal of PuBr/Cy. A series of trans-ThX4(OPCy3)2 (X = Cl, ThCl/Cy; Br, ThBr/Cy; I, ThI/Cy) complexes were synthesized for comparison to PuBr/Cy. The triphenylphosphine oxide, OPPh3, complexes, trans-AnI4(OPPh3)2 (An = Th, ThI/Ph; U, UI/Ph), were also synthesized for comparison, completing the series trans-UX4(OPPh3)2 (X = Cl, Br, I), UX/Ph. To enable the synthesis of ThI/Cy and ThI/Ph, a new nonaqueous thorium iodide starting material, ThI4(Et2O)2, was synthesized. The syntheses of organic solvent soluble ThI4L2 (L = Et2O, OPCy3, and OPPh3) are the first examples of crystallographically characterized neutral thorium tetraiodide materials beyond binary ThI4. To show the viability of ThI4(Et2O)2 as a starting material for organothorium chemistry, (C5Me4H)3ThI was synthesized and crystallographically characterized.
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Styrene-maleic acid copolymers (SMAs), and related amphiphilic copolymers, are promising tools for isolating and studying integral membrane proteins in a native-like state. However, they do not exhibit this ability universally, as several reports have found that SMAs and related amphiphilic copolymers show little to no efficiency when extracting specific membrane proteins. Recently, it was discovered that esterified SMAs could enhance the selective extraction of trimeric Photosystem I from the thylakoid membranes of thermophilic cyanobacteria; however, these polymers are susceptible to saponification that can result from harsh preparation or storage conditions. To address this concern, we herein describe the development of α-olefin-maleic acid copolymers (αMAs) that can extract trimeric PSI from cyanobacterial membranes with the highest extraction efficiencies observed when using any amphiphilic copolymers, including diisobutylene-co-maleic acid (DIBMA) and functionalized SMA samples. Furthermore, we will show that αMAs facilitate the formation of photosystem I-containing nanodiscs that retain an annulus of native lipids and a native-like activity. We also highlight how αMAs provide an agile, tailorable synthetic platform that enables fine-tuning hydrophobicity, controllable molar mass, and consistent monomer incorporation while overcoming shortcomings of prior amphiphilic copolymers.
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Complexo de Proteína do Fotossistema I , Estireno , Bicamadas Lipídicas , Poliestirenos , Alcenos , Proteínas de MembranaRESUMO
Few reviews on procedural fidelity-the degree to which procedures are implemented as designed-provide details to gauge the quality of fidelity reporting in behavior-analytic research. This review focused on experiments in the Journal of Applied Behavior Analysis (2006-2021) with "integrity" or "fidelity" in the abstract or body. When fidelity data were collected, the coders characterized measurement details (e.g., description of calculation, report of single or multiple values, frequency of fidelity checks, checklist use). The researchers found increasing trends in describing the calculation(s), reporting multiple values, and stating the frequency of measurement. Few studies described using a checklist. Most studies reported fidelity as a percentage, with high obtained values (M = 97%). When not collecting fidelity data was stated as a limitation, authors were unlikely to provide a rationale for the omission. We discuss recommendations for reporting procedural fidelity to increase the quality of and transparency in behavior-analytic research.