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Animal movement is controlled by motor neurons (MNs), which project out of the central nervous system to activate muscles1. MN activity is coordinated by complex premotor networks that facilitate the contribution of individual muscles to many different behaviours2-6. Here we use connectomics7 to analyse the wiring logic of premotor circuits controlling the Drosophila leg and wing. We find that both premotor networks cluster into modules that link MNs innervating muscles with related functions. Within most leg motor modules, the synaptic weights of each premotor neuron are proportional to the size of their target MNs, establishing a circuit basis for hierarchical MN recruitment. By contrast, wing premotor networks lack proportional synaptic connectivity, which may enable more flexible recruitment of wing steering muscles. Through comparison of the architecture of distinct motor control systems within the same animal, we identify common principles of premotor network organization and specializations that reflect the unique biomechanical constraints and evolutionary origins of leg and wing motor control.
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Conectoma , Drosophila melanogaster , Extremidades , Neurônios Motores , Vias Neurais , Sinapses , Asas de Animais , Animais , Feminino , Masculino , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/citologia , Drosophila melanogaster/fisiologia , Extremidades/inervação , Extremidades/fisiologia , Neurônios Motores/fisiologia , Movimento/fisiologia , Músculos/inervação , Músculos/fisiologia , Rede Nervosa/anatomia & histologia , Rede Nervosa/citologia , Rede Nervosa/fisiologia , Vias Neurais/anatomia & histologia , Vias Neurais/citologia , Vias Neurais/fisiologia , Sinapses/fisiologia , Asas de Animais/inervação , Asas de Animais/fisiologiaRESUMO
A deep understanding of how the brain controls behaviour requires mapping neural circuits down to the muscles that they control. Here, we apply automated tools to segment neurons and identify synapses in an electron microscopy dataset of an adult female Drosophila melanogaster ventral nerve cord (VNC)1, which functions like the vertebrate spinal cord to sense and control the body. We find that the fly VNC contains roughly 45 million synapses and 14,600 neuronal cell bodies. To interpret the output of the connectome, we mapped the muscle targets of leg and wing motor neurons using genetic driver lines2 and X-ray holographic nanotomography3. With this motor neuron atlas, we identified neural circuits that coordinate leg and wing movements during take-off. We provide the reconstruction of VNC circuits, the motor neuron atlas and tools for programmatic and interactive access as resources to support experimental and theoretical studies of how the nervous system controls behaviour.
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Conectoma , Drosophila melanogaster , Neurônios Motores , Tecido Nervoso , Vias Neurais , Sinapses , Animais , Feminino , Conjuntos de Dados como Assunto , Drosophila melanogaster/anatomia & histologia , Drosophila melanogaster/citologia , Drosophila melanogaster/fisiologia , Drosophila melanogaster/ultraestrutura , Extremidades/fisiologia , Extremidades/inervação , Holografia , Microscopia Eletrônica , Neurônios Motores/citologia , Neurônios Motores/fisiologia , Neurônios Motores/ultraestrutura , Movimento , Músculos/inervação , Músculos/fisiologia , Tecido Nervoso/anatomia & histologia , Tecido Nervoso/citologia , Tecido Nervoso/fisiologia , Tecido Nervoso/ultraestrutura , Vias Neurais/citologia , Vias Neurais/fisiologia , Vias Neurais/ultraestrutura , Sinapses/fisiologia , Sinapses/ultraestrutura , Tomografia por Raios X , Asas de Animais/inervação , Asas de Animais/fisiologiaRESUMO
SF3B is a multi-protein complex essential for branch site (BS) recognition and selection during pre-mRNA splicing. Several splicing modulators with antitumor activity bind SF3B and thereby modulate splicing. Here we report the crystal structure of a human SF3B core in complex with pladienolide B (PB), a macrocyclic splicing modulator and potent inhibitor of tumor cell proliferation. PB stalls SF3B in an open conformation by acting like a wedge within a hinge, modulating SF3B's transition to the closed conformation needed to form the BS adenosine-binding pocket and stably accommodate the BS/U2 duplex. This work explains the structural basis for the splicing modulation activity of PB and related compounds, and reveals key interactions between SF3B and a common pharmacophore, providing a framework for future structure-based drug design.
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Antineoplásicos/farmacologia , Compostos de Epóxi/farmacologia , Macrolídeos/farmacologia , Fosfoproteínas/metabolismo , Fatores de Processamento de RNA/metabolismo , Splicing de RNA/efeitos dos fármacos , Adenosina/metabolismo , Animais , Antineoplásicos/química , Antineoplásicos/metabolismo , Sítios de Ligação , Proteínas de Transporte/metabolismo , Proliferação de Células/efeitos dos fármacos , Desenho de Fármacos , Compostos de Epóxi/química , Compostos de Epóxi/metabolismo , Células HCT116 , Células HeLa , Humanos , Macrolídeos/química , Macrolídeos/metabolismo , Modelos Moleculares , Complexos Multiproteicos , Fosfoproteínas/química , Fosfoproteínas/genética , Ligação Proteica , Conformação Proteica , Precursores de RNA/genética , Precursores de RNA/metabolismo , Fatores de Processamento de RNA/química , Fatores de Processamento de RNA/genética , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA , Células Sf9 , Relação Estrutura-Atividade , TransativadoresRESUMO
Somatic mutations in spliceosome proteins lead to dysregulated RNA splicing and are observed in a variety of cancers. These genetic aberrations may offer a potential intervention point for targeted therapeutics. SF3B1, part of the U2 small nuclear RNP (snRNP), is targeted by splicing modulators, including E7107, the first to enter clinical trials, and, more recently, H3B-8800. Modulating splicing represents a first-in-class opportunity in drug discovery, and elucidating the structural basis for the mode of action opens up new possibilities for structure-based drug design. Here, we present the cryogenic electron microscopy (cryo-EM) structure of the SF3b subcomplex (SF3B1, SF3B3, PHF5A, and SF3B5) bound to E7107 at 3.95 Å. This structure shows that E7107 binds in the branch point adenosine-binding pocket, forming close contacts with key residues that confer resistance upon mutation: SF3B1R1074H and PHF5AY36C The structure suggests a model in which splicing modulators interfere with branch point adenosine recognition and supports a substrate competitive mechanism of action (MOA). Using several related chemical probes, we validate the pose of the compound and support their substrate competitive MOA by comparing their activity against both strong and weak pre-mRNA substrates. Finally, we present functional data and structure-activity relationship (SAR) on the PHF5AR38C mutation that sensitizes cells to some chemical probes but not others. Developing small molecule splicing modulators represents a promising therapeutic approach for a variety of diseases, and this work provides a significant step in enabling structure-based drug design for these elaborate natural products. Importantly, this work also demonstrates that the utilization of cryo-EM in drug discovery is coming of age.
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Compostos de Epóxi/química , Macrolídeos/química , Fosfoproteínas/química , Fatores de Processamento de RNA/química , Splicing de RNA/efeitos dos fármacos , Spliceossomos/efeitos dos fármacos , Proteínas de Transporte/química , Proteínas de Transporte/genética , Proteínas de Transporte/isolamento & purificação , Microscopia Crioeletrônica , Modelos Moleculares , Mutação , Fosfoproteínas/isolamento & purificação , Precursores de RNA/metabolismo , Fatores de Processamento de RNA/isolamento & purificação , RNA Mensageiro/metabolismo , Proteínas de Ligação a RNA , TransativadoresRESUMO
OBJECTIVE: To develop and update evidence-based and consensus-based guidelines on laparoscopic and robotic pancreatic surgery. SUMMARY BACKGROUND DATA: Minimally invasive pancreatic surgery (MIPS), including laparoscopic and robotic surgery, is complex and technically demanding. Minimizing the risk for patients requires stringent, evidence-based guidelines. Since the International Miami Guidelines on MIPS in 2019, new developments and key publications have been reported, necessitating an update. METHODS: Evidence-based guidelines on 22 topics in 8 domains were proposed: terminology, indications, patients, procedures, surgical techniques and instrumentation, assessment tools, implementation and training, and artificial intelligence. The Brescia Internationally Validated European Guidelines on Minimally Invasive Pancreatic Surgery (EGUMIPS, September 2022) used the Scottish Intercollegiate Guidelines Network (SIGN) methodology to assess the evidence and develop guideline recommendations, the Delphi method to establish consensus on the recommendations among the Expert Committee, and the AGREE II-GRS tool for guideline quality assessment and external validation by a Validation Committee. RESULTS: Overall, 27 European experts, 6 international experts, 22 international Validation Committee members, 11 Jury Committee members, 18 Research Committee members, and 121 registered attendees of the 2-day meeting were involved in the development and validation of the guidelines. In total, 98 recommendations were developed, including 33 on laparoscopic, 34 on robotic, and 31 on general MIPS, covering 22 topics in 8 domains. Out of 98 recommendations, 97 reached at least 80% consensus among the experts and congress attendees, and all recommendations were externally validated by the Validation Committee. CONCLUSIONS: The EGUMIPS evidence-based guidelines on laparoscopic and robotic MIPS can be applied in current clinical practice to provide guidance to patients, surgeons, policy-makers, and medical societies.
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Laparoscopia , Cirurgiões , Humanos , Inteligência Artificial , Pâncreas/cirurgia , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Laparoscopia/métodosRESUMO
Background Current clinical imaging modalities such as CT and MRI provide resolution adequate to diagnose cardiovascular diseases but cannot depict detailed structural features in the heart across length scales. Hierarchical phase-contrast tomography (HiP-CT) uses fourth-generation synchrotron sources with improved x-ray brilliance and high energies to provide micron-resolution imaging of intact adult organs with unprecedented detail. Purpose To evaluate the capability of HiP-CT to depict the macro- to microanatomy of structurally normal and abnormal adult human hearts ex vivo. Materials and Methods Between February 2021 and September 2023, two adult human donor hearts were obtained, fixed in formalin, and prepared using a mixture of crushed agar in a 70% ethanol solution. One heart was from a 63-year-old White male without known cardiac disease, and the other was from an 87-year-old White female with a history of multiple known cardiovascular pathologies including ischemic heart disease, hypertension, and atrial fibrillation. Nondestructive ex vivo imaging of these hearts without exogenous contrast agent was performed using HiP-CT at the European Synchrotron Radiation Facility. Results HiP-CT demonstrated the capacity for high-spatial-resolution, multiscale cardiac imaging ex vivo, revealing histologic-level detail of the myocardium, valves, coronary arteries, and cardiac conduction system across length scales. Virtual sectioning of the cardiac conduction system provided information on fatty infiltration, vascular supply, and pathways between the cardiac nodes and adjacent structures. HiP-CT achieved resolutions ranging from gross (isotropic voxels of approximately 20 µm) to microscopic (approximately 6.4-µm voxel size) to cellular (approximately 2.3-µm voxel size) in scale. The potential for quantitative assessment of features in health and disease was demonstrated. Conclusion HiP-CT provided high-spatial-resolution, three-dimensional images of structurally normal and diseased ex vivo adult human hearts. Whole-heart image volumes were obtained with isotropic voxels of approximately 20 µm, and local regions of interest were obtained with resolution down to 2.3-6.4 µm without the need for sectioning, destructive techniques, or exogenous contrast agents. Published under a CC BY 4.0 license Supplemental material is available for this article. See also the editorial by Bluemke and Pourmorteza in this issue.
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Coração , Tomografia Computadorizada por Raios X , Humanos , Pessoa de Meia-Idade , Masculino , Feminino , Tomografia Computadorizada por Raios X/métodos , Coração/diagnóstico por imagem , Idoso de 80 Anos ou mais , Cardiopatias/diagnóstico por imagem , SíncrotronsRESUMO
Despite centuries of investigation, certain aspects of left ventricular anatomy remain either controversial or uncertain. We make no claims to have resolved these issues, but our review, based on our current knowledge of development, hopefully identifies the issues requiring further investigation. When first formed, the left ventricle had only inlet and apical components. With the expansion of the atrioventricular canal, the developing ventricle cedes part of its inlet to the right ventricle whilst retaining the larger parts of the cushions dividing the atrioventricular canal. Further remodelling of the interventricular communication provides the ventricle with its outlet, with the aortic root being transferred to the left ventricle along with the newly formed myocardium supporting its leaflets. The definitive ventricle possesses inlet, apical and outlet parts. The inlet component is guarded by the mitral valve, with its leaflets, in the normal heart, supported by papillary muscles located infero-septally and supero-laterally. There is but a solitary zone of apposition between the leaflets, which we suggest are best described as being aortic and mural. The trabeculated component extends beyond the inlet to the apex and is confluent with the outlet part, which supports the aortic root. The leaflets of the aortic valve are supported in semilunar fashion within the root, with the ventricular cavity extending to the sinutubular junction. The myocardial-arterial junction, however, stops well short of the sinutubular junction, with myocardium found only at the bases of the sinuses, giving rise to the coronary arteries. We argue that the relationships between the various components should now be described using attitudinally appropriate terms rather than describing them as if the heart is removed from the body and positioned on its apex.
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Ventrículos do Coração , Humanos , Ventrículos do Coração/anatomia & histologia , AnimaisRESUMO
OBJECTIVE: Treatment of juxtarenal and complex neck abdominal aortic aneurysms (AAAs) is now commonly by endovascular rather than open surgical repair (OSR). Published comparisons show poor validity and scientific precision. UK-COMPASS is a comparative cohort study of endovascular treatments vs. OSR for patients with an AAA unsuitable for standard on label endovascular aneurysm repair (EVAR). METHODS: All procedures for AAA in England (November 2017 to October 2019) were identified, AAA anatomy assessed in a Corelab, peri-operative risk scores determined, and propensity scoring used to identify patients suitable for either endovascular treatment or OSR. Patients were stratified by aneurysm neck length (0 - 4 mm, 5 - 9 mm, or ≥ 10 mm) and operative risk; the highest quartile was considered high risk and the remainder standard risk. Death was the primary outcome measure. Endovascular treatments included fenestrated EVAR (FEVAR) and off label standard EVAR (± adjuncts). RESULTS: Among 8 994 patients, 2 757 had AAAs that were juxtarenal, short neck, or complex neck in morphology. Propensity score stratification and adjustment method comparisons included 1 916 patients. Widespread off label use of standard EVAR devices was noted (35.6% of patients). The adjusted peri-operative mortality rate was 2.9%, lower for EVAR (1.2%; p = .001) and FEVAR (2.2%; p = .001) than OSR (4.5%). In standard risk patients with a 0 - 4 mm neck, the mortality rate was 7.4% following OSR and 2.3% following FEVAR. Differences were smaller for patients with a neck length ≥ 5 mm: 2.1% OSR vs. 1.0% FEVAR. At 3.5 years of follow up, the overall mortality rate was 20.7% in the whole study population, higher following FEVAR (27.6%) and EVAR (25.2%) than after OSR (14.2%). However, in the 0 - 4 mm neck subgroup, overall survival remained equivalent. The aneurysm related mortality rate was equivalent between treatments, but re-intervention was more common after EVAR and FEVAR than OSR. CONCLUSION: FEVAR proves notably safer than OSR in the peri-operative period for juxtarenal aneurysms (0 - 4 mm neck length), with comparable midterm survival. For patients with short neck (5 - 9 mm) and complex neck (≥ 10 mm) AAAs, overall survival was worse in endovascularly treated patients compared with OSR despite relative peri-operative safety. This warrants further research and a re-appraisal of the current clinical application of endovascular strategies, particularly in patients with poor general survival outlook owing to comorbidity and age.
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Despite the availability of transuranic elements increasing in recent years, our understanding of their most basic and inherent radiation chemistry is limited and yet essential for the accurate interpretation of their physical and chemical properties. Here, we explore the transient interactions between trivalent californium ions (Cf3+) and select inorganic radicals arising from the radiolytic decomposition of common anions and functional group constituents, specifically the dichlorine (Cl2â¢-) and sulfate (SO4â¢-) radical anions. Chemical kinetics, as measured using integrated electron pulse radiolysis and transient absorption spectroscopy techniques, are presented for the reactions of these two oxidizing radicals with Cf3+ ions. The derived and ionic strength-corrected second-order rate coefficients (k) for these radiation-induced processes are k(Cf3+ + Cl2â¢-) = (8.28 ± 0.61) × 105 M-1 s-1 and k(Cf3+ + SO4â¢-) = (9.50 ± 0.43) × 108 M-1 s-1 under ambient temperature conditions (22 ± 1 °C).
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Opportunistic bacterial infections are common in insect populations but there is little information on how they are acquired or transmitted. We tested the hypothesis that Macrocheles mites can transmit systemic bacterial infections between Drosophila hosts. We found that 24% of mites acquired detectable levels of bacteria after feeding on infected flies and 87% of infected mites passed bacteria to naïve recipient flies. The probability that a mite could pass Serratia from an infected donor fly to a naïve recipient fly was 27.1%. These data demonstrate that Macrocheles mites are capable of serving as vectors of bacterial infection between insects.
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Ácaros , Animais , Ácaros/microbiologia , Ácaros/fisiologia , Drosophila/microbiologia , Drosophila/parasitologia , Serratia/fisiologia , Drosophila melanogaster/microbiologiaRESUMO
X-ray phase contrast imaging (X-PCI) is a powerful technique for high-resolution, three-dimensional imaging of soft tissue samples in a non-destructive manner. In this technical report, we assess the quality of standard histopathological techniques performed on formalin-fixed, paraffin-embedded (FFPE) human tissue samples that have been irradiated with different doses of X-rays in the context of an X-PCI experiment. The data from this study demonstrate that routine histochemical and immunohistochemical staining quality as well as DNA and RNA analyses are not affected by previous X-PCI on human FFPE samples. From these data we conclude it is feasible and acceptable to perform X-PCI on FFPE human biopsies.
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Intervenção Coronária Percutânea , Síncrotrons , Humanos , Raios X , Estudos de Viabilidade , Imageamento Tridimensional , Inclusão em Parafina , Formaldeído , Fixação de TecidosRESUMO
BACKGROUND: Penile prosthesis implantation offers a durable, safe, and effective treatment option for male erectile dysfunction; however, many urologists feel apprehensive and uncomfortable placing penile prostheses due to limited training, low surgical experience, and intra- and postoperative complication management. AIM: To compare a previously validated hydrogel inflatable penile prosthesis (IPP) training model with cadaver simulations across 4 main categories: anatomic replication and realism, procedural replication and realism, educational effectiveness, and efficacy and safety. METHODS: An overall 88 participants (15 attendings, 18 fellows, and 55 residents) performed guided IPP placements on a cadaver and a hydrogel model. Based on a 5-point Likert scale, postsurveys were used to assess the participants' opinions regarding anatomic replication and realism, procedural replication and realism, educational effectiveness, and safety between the hydrogel model and cadavers. OUTCOMES: A direct head-to-head scenario was created, allowing participants to fully utilize the hydrogel model and cadaver, which ensured the most accurate comparison possible. RESULTS: A total of 84% agreed that the hydrogel model replicates the relevant human cadaveric anatomy for the procedure, whereas 69% agreed that the hydrogel tissue resembles the appearance of cadaveric tissue. Regarding the pubic bone, outer skin, corporal bodies, dartos layer, and scrotum, 79%, 74%, 82%, 46%, and 30% respectively agreed that the hydrogel tissue resembled the texture/behavior of cadavers. Furthermore, 66% of participants agreed that the hydrogel model replicates all the procedural steps. Specifically, participants agreed that the model replicates the skin incision/dartos dissection (74%), placement of stay suture and corporotomy (92%), corporal dilation (81%), measurement of prosthetic size (98%), reservoir placement (43%), IPP placement (91%), scrotal pump placement (48%), and skin closure (51%). Finally, 86%, 93%, and 78% agreed that the hydrogel model is useful for improving technical skills, as a teaching/practicing tool, and as an evaluation tool, respectively. To conclude, 81% of participants stated that they would include the hydrogel model platform in their current training. CLINICAL IMPLICATIONS: By replicating the IPP procedure, the hydrogel model offers an additional high-fidelity training opportunity for urologists, allowing them to improve their skills and confidence in placing penile prostheses, with the goal of improving patient surgical outcomes. STRENGTHS AND LIMITATIONS: The hydrogel training model allows users to perform the entire IPP placement procedure with high anatomic realism and educational effectiveness, maintaining many of the high-fidelity benefits seen in cadavers while improving safety and accessibility. CONCLUSION: Ultimately, this high-fidelity nonbiohazardous training model can be used to supplement and bolster current IPP training curriculums.
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Disfunção Erétil , Implante Peniano , Prótese de Pênis , Masculino , Humanos , Prótese de Pênis/efeitos adversos , Hidrogéis , Implante Peniano/métodos , Disfunção Erétil/cirurgia , Disfunção Erétil/etiologia , CadáverRESUMO
The impact of trivalent lanthanide ion complexation and temperature on the chemical reactivity of N,N,N',N'-tetraoctyl diglycolamide (TODGA) with the n-dodecane radical cation (RHË+) has been measured by electron pulse radiolysis and evaluated by quantum mechanical calculations. Additionally, Arrhenius parameters were determined for the reaction of the non-complexed TODGA ligand with the RHË+ from 10-40 °C, giving the activation energy (Ea = 17.43 ± 1.64 kJ mol-1) and pre-exponential factor (A = (2.36 ± 0.05) × 1013 M-1 s-1). The complexation of Nd(III), Gd(III), and Yb(III) ions by TODGA yielded [LnIII(TODGA)3(NO3)3] complexes that exhibited significantly increased reactivity (up to 9.3× faster) with the RHË+, relative to the non-complexed ligand: k([LnIII(TODGA)3(NO3)3] + RHË+) = (8.99 ± 0.93) × 1010, (2.88 ± 0.40) × 1010, and (1.53 ± 0.34) × 1010 M-1 s-1, for Nd(III), Gd(III), and Yb(III) ions, respectively. The rate coefficient enhancement measured for these complexes exhibited a dependence on atomic number, decreasing as the lanthanide series was traversed. Preliminary reaction free energy calculations-based on a model [LnIII(TOGDA)]3+ complex system-indicate that both electron/hole and proton transfer reactions are energetically unfavorable for complexed TODGA. Furthermore, complementary average local ionization energy calculations showed that the most reactive region of model N,N,N',N'-tetraethyl diglycolamide (TEDGA) complexes, [LnIII(TEGDA)3(NO3)3], toward electrophilic attack is for the coordinated nitrate (NO3-) counter anions. Therefore, it is possible that radical reactions with the complexed NO3- counter anions dominate the differences in rates seen for the [LnIII(TODGA)3(NO3)3] complexes, and are likely responsible for the reported radioprotection in the presence of TODGA complexes.
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The fate of fission-product iodine is critical for the deployment of next generation molten salt reactor technologies, owing to its volatility and biological impacts if it were to be released into the environment. To date, little is known on how ionizing radiation fields influence the redox chemistry, speciation, and transport of iodine in high temperature molten salts. Here we employ picosecond electron pulse irradiation techniques to elucidate for the first time the impact of iodide ions (I-) on the speciation and chemical kinetics of the primary radiation-induced transient radicals generated in molten chloride salt mixtures (eS- and Cl2Ë-) as a function of temperature (400-700 °C). In the presence of I- ions (≥ 1 wt% KI in LiCl-KCl eutectic), we find that the transient spectrum following the electron pulse is composed of at least three overlapping species: the eS- and the Cl2Ë- and IClË- radical anions, for which a deconvoluted spectrum of the latter is reported here for the first time in molten salts. This new transient spectrum was consistent with gas phase density functional theory calculations. The lifetime of the eS- was unaffected by the addition of I- ions. The newly observed interhalogen radical anion, IClË-, exhibited a lifetime on the order of microseconds over the investigated temperature range. The associated chemical kinetics indicate that the predominate mechanism of IClË- decay is via reaction with the Cl2Ë- radical anion. The iodine containing product of this reaction is expected to be ICl2-, which will have implications for the transport of fission-product iodine in MSR technologies.
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The protein kinase PKN2 is required for embryonic development and PKN2 knockout mice die as a result of failure in the expansion of mesoderm, cardiac development and neural tube closure. In the adult, cardiomyocyte PKN2 and PKN1 (in combination) are required for cardiac adaptation to pressure-overload. The specific role of PKN2 in contractile cardiomyocytes during development and its role in the adult heart remain to be fully established. We used mice with cardiomyocyte-directed knockout of PKN2 or global PKN2 haploinsufficiency to assess cardiac development and function using high resolution episcopic microscopy, MRI, micro-CT and echocardiography. Biochemical and histological changes were also assessed. Cardiomyocyte-directed PKN2 knockout embryos displayed striking abnormalities in the compact myocardium, with frequent myocardial clefts and diverticula, ventricular septal defects and abnormal heart shape. The sub-Mendelian homozygous knockout survivors developed cardiac failure. RNASeq data showed up-regulation of PKN2 in patients with dilated cardiomyopathy, suggesting an involvement in adult heart disease. Given the rarity of homozygous survivors with cardiomyocyte-specific deletion of PKN2, the requirement for PKN2 in adult mice was explored using the constitutive heterozygous PKN2 knockout. Cardiac hypertrophy resulting from hypertension induced by angiotensin II was reduced in these haploinsufficient PKN2 mice relative to wild-type littermates, with suppression of cardiomyocyte hypertrophy and cardiac fibrosis. It is concluded that cardiomyocyte PKN2 is essential for heart development and the formation of compact myocardium and is also required for cardiac hypertrophy in hypertension. Thus, PKN signalling may offer therapeutic options for managing congenital and adult heart diseases.
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Cardiomiopatias , Hipertensão , Proteína Quinase C/metabolismo , Angiotensina II/metabolismo , Angiotensina II/farmacologia , Animais , Cardiomegalia/metabolismo , Cardiomiopatias/metabolismo , Cardiomiopatias/patologia , Feminino , Hipertensão/metabolismo , Hipertensão/patologia , Camundongos , Camundongos Knockout , Miocárdio/metabolismo , Miócitos Cardíacos/metabolismo , GravidezRESUMO
Readers simulate story characters' emotions, memories, and perceptual experiences. The current study consists of three experiments that investigated whether survival threat would amplify the mnemonic experience of a narrative. First, a replication study of Nairne et al. (Journal of Experimental Psychology: Learning, Memory, and Cognition, 33 (2), 263-273, 2007) was conducted with minor methodological alternations and yielded improved recall for participants imagining themselves in a survival scenario over a moving scenario (Experiment 1). In Experiments 2 and 3, participants read stories about a character either stranded in the grasslands or moving to a foreign land. Improved recall for objects included in the story (Experiments 2 and 3) and recognition of story details (Experiment 3) was found when the character was in a survival situation. The largest effects were observed when the reader was asked to imagine themselves as the story character (Experiment 3). Overall, readers remembered survival-relevant details as if they were experiencing the story character's plight. These results extend research showing that survival processing enhances memory for word lists (e.g., Nairne et al., Psychological Science, 19 (2), 176-180, 2008).
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Cognição , Rememoração Mental , Humanos , Memória , Reconhecimento Psicológico , EmoçõesRESUMO
PURPOSE: To identify clinical predictors and build prediction models for 1-year patient-reported outcomes measures (PROMs) after lumbar decompressive surgery for disc herniation or spinal stenosis. METHODS: The study included 1835 cases, with or without additional single-level fusion, from a single centre from 2008 through 2020. General linear models imputed with 37 clinical variables identified 18 significant 1-year PROM predictors for retention in development models. Interaction of surgical indication with each predictor was tested. Temporal validation was conducted at the same centre on cases through 2021. R2 was used to measure goodness-of-fit, and area under curve (AUC) used to measure classification to a satisfactory symptom state (Oswestry Disability Index (ODI) ≤ 22; back or leg pain ≤ 30 out of 100). RESULTS: A total 1228 (67%) had complete data for inclusion in model development. Predictors of ODI were baseline PROMs (ODI, back pain, leg pain), work status, condition duration, previous lumbar operation, multiple-joint osteoarthritis, female, diabetes, current smoker, rheumatic disorder, lower limb arthroplasty, mobility aided, provider status, facet cyst, scoliosis, and age, with BMI significantly associated with stenosis. Temporal validation (n = 188) found the ODI model R2 was 0.29 (95% confidence intervals (CI) 0.18-0.40) and AUC was 0.74 (95% CI 0.67-0.81). Back and leg pain models had lower R2 (0.12-0.14) and AUC (0.68-0.69) values. CONCLUSION: Important PROM predictors are baseline PROMs, specific co-morbidities, work status, condition duration, previous lumbar operation, female, and smoking status. The ODI model predicted the likelihood of achieving a satisfactory state of both disability and pain.
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Deslocamento do Disco Intervertebral , Modelos Estatísticos , Humanos , Feminino , Resultado do Tratamento , Prognóstico , Dor nas Costas/cirurgia , Deslocamento do Disco Intervertebral/cirurgia , Vértebras Lombares/cirurgiaRESUMO
We define a family of C1 functions, which we call "nowhere coexpanding functions," that is closed under composition and includes all C3 functions with non-positive Schwarzian derivatives. We establish results on the number and nature of the fixed points of these functions, including a generalization of a classic result of Singer.
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AIMS: To observe, describe, and evaluate management and timing of intervention for patients with untreated thoracic aortic aneurysms. METHODS AND RESULTS: Prospective study of UK National Health Service (NHS) patients aged ≥18 years, with new/existing arch or descending thoracic aortic aneurysms of ≥4 cm diameter, followed up until death, intervention, withdrawal, or July 2019. Outcomes were aneurysm growth, survival, quality of life (using the EQ-5D-5L utility index), and hospital admissions. Between 2014 and 2018, 886 patients were recruited from 30 NHS vascular/cardiothoracic units. Maximum aneurysm diameter was in the descending aorta in 725 (82%) patients, growing at 0.2 cm (0.17-0.24) per year. Aneurysms of ≥4 cm in the arch increased by 0.07 cm (0.02-0.12) per year. Baseline diameter was related to age and comorbidities, and no clinical correlates of growth were found. During follow-up, 129 patients died, 64 from aneurysm-related events. Adjusting for age, sex, and New York Heart Association dyspnoea index, risk of death increased with aneurysm size at baseline [hazard ratio (HR): 1.88 (95% confidence interval: 1.64-2.16) per cm, P < 0.001] and with growth [HR: 2.02 (1.70-2.41) per cm, P < 0.001]. Hospital admissions increased with aneurysm size [relative risk: 1.21 (1.05-1.38) per cm, P = 0.008]. Quality of life decreased annually for each 10-year increase in age [-0.013 (-0.019 to -0.007), P < 0.001] and for current smoking [-0.043 (-0.064 to -0.023), P = 0.004]. Aneurysm size was not associated with change in quality of life. CONCLUSION: International guidelines should consider increasing monitoring intervals to 12 months for small aneurysms and increasing intervention thresholds. Individualized decisions about surveillance/intervention should consider age, sex, size, growth, patient characteristics, and surgical risk.
Assuntos
Aneurisma da Aorta Torácica , Adolescente , Adulto , Aorta Torácica/cirurgia , Aneurisma da Aorta Torácica/cirurgia , Seguimentos , Humanos , Estudos Prospectivos , Qualidade de Vida , Medicina EstatalRESUMO
Over the past 2 decades, several categorizations have been proposed for the abnormalities of the aortic root. These schemes have mostly been devoid of input from specialists of congenital cardiac disease. The aim of this review is to provide a classification, from the perspective of these specialists, based on an understanding of normal and abnormal morphogenesis and anatomy, with emphasis placed on the features of clinical and surgical relevance. We contend that the description of the congenitally malformed aortic root is simplified when approached in a fashion that recognizes the normal root to be made up of 3 leaflets, supported by their own sinuses, with the sinuses themselves separated by the interleaflet triangles. The malformed root, usually found in the setting of 3 sinuses, can also be found with 2 sinuses, and very rarely with 4 sinuses. This permits description of trisinuate, bisinuate, and quadrisinuate variants, respectively. This feature then provides the basis for classification of the anatomical and functional number of leaflets present. By offering standardized terms and definitions, we submit that our classification will be suitable for those working in all cardiac specialties, whether pediatric or adult. It is of equal value in the settings of acquired or congenital cardiac disease. Our recommendations will serve to amend and/or add to the existing International Paediatric and Congenital Cardiac Code, along with the Eleventh iteration of the International Classification of Diseases provided by the World Health Organization.