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Spermatozoa have a streamlined shape to swim through the oviduct to fertilize oocytes. To become svelte spermatozoa, spermatid cytoplasm must be eliminated in several steps including sperm release, which is part of spermiation. Although this process has been well observed, the molecular mechanisms that underlie it remain unclear. In male germ cells, there are membraneless organelles called nuage, which are observed by electron microscopy in various forms of dense material. Reticulated body (RB) and chromatoid body remnant (CR) are two types of nuage in spermatids, but the functions of both are unknown. Using CRISPR/Cas9 technology, we deleted the entire coding sequence of testis-specific serine kinase substrate (TSKS) in mice and demonstrate that TSKS is essential for male fertility through the formation of both RB and CR, prominent sites of TSKS localization. Due to the lack of TSKS-derived nuage (TDN), the cytoplasmic contents cannot be eliminated from spermatid cytoplasm in Tsks knockout mice, resulting in excess residual cytoplasm with an abundance of cytoplasmic materials and inducing an apoptotic response. In addition, ectopic expression of TSKS in cells results in formation of amorphous nuage-like structures; dephosphorylation of TSKS helps to induce nuage, while phosphorylation of TSKS blocks the formation. Our results indicate that TSKS and TDN are essential for spermiation and male fertility by eliminating cytoplasmic contents from the spermatid cytoplasm.
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Proteínas do Citoesqueleto , Grânulos de Ribonucleoproteínas de Células Germinativas , Fosfoproteínas , Espermátides , Animais , Masculino , Camundongos , Citoplasma , Citosol , Camundongos Knockout , Sêmen , Proteínas do Citoesqueleto/genética , Fosfoproteínas/genéticaRESUMO
Sirtuin3 (Sirt3) is a nicotinamide adenine dinucleotide enzyme that contributes to aging, cancer, and neurodegenerative diseases. Recent studies have reported that Sirt3 exerts anti-inflammatory effects in several neuropathophysiological disorders. As epilepsy is a common neurological disease, in the present study, we investigated the role of Sirt3 in astrocyte activation and inflammatory processes after epileptic seizures. We found the elevated expression of Sirt3 within reactive astrocytes as well as in the surrounding cells in the hippocampus of patients with temporal lobe epilepsy and a mouse model of pilocarpine-induced status epilepticus (SE). The upregulation of Sirt3 by treatment with adjudin, a potential Sirt3 activator, alleviated SE-induced astrocyte activation; whereas, Sirt3 deficiency exacerbated astrocyte activation in the hippocampus after SE. In addition, our results showed that Sirt3 upregulation attenuated the activation of Notch1 signaling, nuclear factor kappa B (NF-κB) activity, and the production of interleukin-1ß (IL1ß) in the hippocampus after SE. By contrast, Sirt3 deficiency enhanced the activity of Notch1/NF-κB signaling and the production of IL1ß. These findings suggest that Sirt3 regulates astrocyte activation by affecting the Notch1/NF-κB signaling pathway, which contributes to the inflammatory response after SE. Therefore, therapies targeting Sirt3 may be a worthy direction for limiting inflammatory responses following epileptic brain injury.
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Epilepsia , Sirtuína 3 , Estado Epiléptico , Animais , Humanos , Camundongos , Astrócitos/metabolismo , Epilepsia/metabolismo , Hipocampo/metabolismo , NF-kappa B/metabolismo , Transdução de Sinais , Sirtuína 3/metabolismo , Estado Epiléptico/induzido quimicamente , Estado Epiléptico/metabolismoRESUMO
To estimate the size of an indoor space, we must analyze the visual boundaries that limit the spatial extent and acoustic cues from reflected interior surfaces. We used fMRI to examine how the brain processes the geometric size of indoor scenes when various types of sensory cues are presented individually or together. Specifically, we asked whether the size of space is represented in a modality-specific way or in an integrative way that combines multimodal cues. In a block-design study, images or sounds that depict small- and large-sized indoor spaces were presented. Visual stimuli were real-world pictures of empty spaces that were small or large. Auditory stimuli were sounds convolved with different reverberations. By using a multivoxel pattern classifier, we asked whether the two sizes of space can be classified in visual, auditory, and visual-auditory combined conditions. We identified both sensory-specific and multimodal representations of the size of space. To further investigate the nature of the multimodal region, we specifically examined whether it contained multimodal information in a coexistent or integrated form. We found that angular gyrus and the right medial frontal gyrus had modality-integrated representation, displaying sensitivity to the match in the spatial size information conveyed through image and sound. Background functional connectivity analysis further demonstrated that the connection between sensory-specific regions and modality-integrated regions increases in the multimodal condition compared with single modality conditions. Our results suggest that spatial size perception relies on both sensory-specific and multimodal representations, as well as their interplay during multimodal perception.
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Mapeamento Encefálico , Encéfalo , Humanos , Mapeamento Encefálico/métodos , Encéfalo/diagnóstico por imagem , Percepção Espacial , Lobo Parietal , Córtex Pré-Frontal , Estimulação Acústica/métodos , Percepção Auditiva , Imageamento por Ressonância Magnética/métodosRESUMO
Modern strides in energy storage underscore the significance of all-solid-state batteries (ASSBs) predicated on solid electrolytes and lithium (Li) metal anodes in response to the demand for safer batteries. Nonetheless, ASSBs are often beleaguered by non-uniform Li deposition during cycling, leading to compromised cell performance from internal short circuits and hindered charge transfer. In this study, the concept of "bottom deposition" is introduced to stabilize metal deposition based on the lithiophilic current collector and a protective layer composed of a polymeric binder and carbon black. The bottom deposition, wherein Li plating ensues between the protective layer and the current collector, circumvents internal short circuits and facilitates uniform volumetric changes of Li. The prepared functional binder for the protective layer presents outstanding mechanical robustness and adhesive properties, which can withstand the volume expansion caused by metal growth. Furthermore, its excellent ion transfer properties promote uniform Li bottom deposition even under a current density of 6 mA·cm-2. Also, scanning electron microscopy analysis reveals a consistent plating/stripping morphology of Li after cycling. Consequently, the proposed system exhibits enhanced electrochemical performance when assessed within the ASSB framework, operating under a configuration marked by a high Li utilization rate reliant on an ultrathin Li.
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The current high-capacity lithium-ion batteries (LIBs), reliant on flammable liquid electrolytes (LEs) and nickel-rich cathodes, are plagued by safety hazards, especially the risk of hazardous gas release stemming from internal side reactions. To address these safety concerns, an electron beam (E-beam)-induced gel polymer electrolyte (E-Gel) is introduced, employing dipentaerythritol hexaacrylate (DPH) as a bi-functional cross-linkable additive (CIA). The dual roles of DPH are exploited through a strategically designed E-beam irradiation process. Applying E-beam irradiation on the pre-cycled cells allows DPH to function as an additive during the initial cycle, establishing a protective layer on the surface of the anode and cathode and as a cross-linker during the E-beam irradiation step, forming a polymer framework. The prepared E-Gel with CIA has superior interfacial compatibility, facilitating lithium-ion diffusion at the electrode/E-Gel interface. The electrochemical assessment of 1.2 Ah pouch cells demonstrates that E-Gel substantially reduces gas release by 2.5 times compared to commercial LEs during the initial formation stage and ensures superior reversible capacity retention even after prolonged cycling at 55 °C. The research underscores the synergy of bifunctional CIA with E-beam technology, paving the way for large-scale production of safe, high-capacity, and commercially viable LIBs.
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All-solid-state batteries (ASSBs) possess the advantage of ensuring safety while simultaneously maximizing energy density, making them suitable for next-generation battery models. In particular, sulfide solid electrolytes (SSEs) are viewed as promising candidates for ASSB electrolytes due to their excellent ionic conductivity. However, a limitation exists in the form of interfacial side reactions occurring between the SSEs and cathode active materials (CAMs), as well as the generation of sulfide-based gases within the SSE. These issues lead to a reduction in the capacity of CAMs and an increase in internal resistance within the cell. To address these challenges, cathode composite materials incorporating zinc oxide (ZnO) are fabricated, effectively reducing various side reactions occurring in CAMs. Acting as a semiconductor, ZnO helps mitigate the rapid oxidation of the solid electrolyte facilitated by an electronic pathway, thereby minimizing side reactions, while maintaining electron pathways to the active material. Additionally, it absorbs sulfide-based gases, thus protecting the lithium ions within CAMs. In this study, the mass spectrometer is employed to observe gas generation phenomena within the ASSB cell. Furthermore, a clear elucidation of the side reactions occurring at the cathode and the causes of capacity reduction in ASSB are provided through density functional theory calculations.
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ConspectusWith the escalating demands of portable electronics, electric vehicles, and grid-scale energy storage systems, the development of next-generation rechargeable batteries, which boasts high energy density, cost effectiveness, and environmental sustainability, becomes imperative. Accelerating these advancements could substantially mitigate detrimental carbon emissions. The pursuit of main objectives has kindled interest in pure silicon as a high-capacity electroactive material, capable of further enhancing the gravimetric and volumetric energy densities compared with traditional graphite counterparts. Despite such promising attributes, pure silicon materials face significant hurdles, primarily due to their drastic volumetric changes during the lithiation/delithiation processes. Volume changes give rise to severe side effects, such as fracturing, pulverization, and delamination, triggering rapid capacity decay. Therefore, mitigating silicon particle fracture remains a primary challenge. Importantly, nanoscale silicon (below 150 nm in size) has shown resilience to stresses induced by repeated volume changes, thereby highlighting its potential as an anode-active material. However, the volume expansion stress not only affects the internal structure of the particle but also disrupts the solid-electrolyte interphase (SEI) layer, formed spontaneously on the outer surface of silicon, causing adverse side reactions. Therefore, despite silicon nanoparticles offering new opportunities, overcoming the associated issues is of paramount importance.Thus, this Account aims to spotlight the significant strides made in the development of pure silicon anodes with particular attention to feature size. From the emergence of nanoscale silicon, the following nanotechnology played a crucial role in growing the particle through nano/microstructuring. Similarly, bulk silicon microparticles gradually surfaced with the post-engineering methods owing to their practical advantages. We briefly discuss the special characteristics of representative examples from bulk silicon engineering and nano/microstructuring, all aimed at overcoming intrinsic challenges, such as limiting large volume changes and stabilizing SEI formation during electrochemical cycling. Subsequently, we outline guidelines for advancing pure silicon anodes to incorporate high mass loading and high energy density. Importantly, these advancements require superior material design and the incorporation of exceptional battery components to ensure compatibility and yield synergistic effects. By broadening the cooperative strategies at the cell and system levels, we anticipate that this Account will provide an insightful analysis of pure silicon anodes and catalyze their practical applications in real battery systems.
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Increased intracranial pressure (ICP) causes disability and mortality in the neurointensive care population. Current methods for monitoring ICP are invasive. We designed a deep learning framework using a domain adversarial neural network to estimate noninvasive ICP, from blood pressure, electrocardiogram, and cerebral blood flow velocity. Our model had a mean of median absolute error of 3.88 ± 3.26 mmHg for the domain adversarial neural network, and 3.94 ± 1.71 mmHg for the domain adversarial transformers. Compared with nonlinear approaches, such as support vector regression, this was 26.7% and 25.7% lower. Our proposed framework provides more accurate noninvasive ICP estimates than currently available. ANN NEUROL 2023;94:196-202.
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Aprendizado Profundo , Hipertensão Intracraniana , Humanos , Pressão Intracraniana/fisiologia , Circulação Cerebrovascular/fisiologia , Pressão Sanguínea/fisiologia , Hipertensão Intracraniana/etiologia , Ultrassonografia Doppler Transcraniana/efeitos adversosRESUMO
In unconscious appearing patients with acute brain injury, wilful brain activation to motor commands without behavioural signs of command following, known as cognitive motor dissociation (CMD), is associated with functional recovery. CMD can be detected by applying machine learning to EEG recorded during motor command presentation in behaviourally unresponsive patients. Identifying patients with CMD carries clinical implications for patient interactions, communication with families, and guidance of therapeutic decisions but underlying mechanisms of CMD remain unknown. By analysing structural lesion patterns and network level dysfunction we tested the hypothesis that, in cases with preserved arousal and command comprehension, a failure to integrate comprehended motor commands with motor outputs underlies CMD. Manual segmentation of T2-fluid attenuated inversion recovery and diffusion weighted imaging sequences quantifying structural injury was performed in consecutive unresponsive patients with acute brain injury (n = 107) who underwent EEG-based CMD assessments and MRI. Lesion pattern analysis was applied to identify lesion patterns common among patients with (n = 21) and without CMD (n = 86). Thalamocortical and cortico-cortical network connectivity were assessed applying ABCD classification of power spectral density plots and weighted pairwise phase consistency (WPPC) to resting EEG, respectively. Two distinct structural lesion patterns were identified on MRI for CMD and three for non-CMD patients. In non-CMD patients, injury to brainstem arousal pathways including the midbrain were seen, while no CMD patients had midbrain lesions. A group of non-CMD patients was identified with injury to the left thalamus, implicating possible language comprehension difficulties. Shared lesion patterns of globus pallidus and putamen were seen for a group of CMD patients, which have been implicated as part of the anterior forebrain mesocircuit in patients with reversible disorders of consciousness. Thalamocortical network dysfunction was less common in CMD patients [ABCD-index 2.3 (interquartile range, IQR 2.1-3.0) versus 1.4 (IQR 1.0-2.0), P < 0.0001; presence of D 36% versus 3%, P = 0.0006], but WPPC was not different. Bilateral cortical lesions were seen in patients with and without CMD. Thalamocortical disruption did not differ for those with CMD, but long-range WPPC was decreased in 1-4 Hz [odds ratio (OR) 0.8; 95% confidence interval (CI) 0.7-0.9] and increased in 14-30 Hz frequency ranges (OR 1.2; 95% CI 1.0-1.5). These structural and functional data implicate a failure of motor command integration at the anterior forebrain mesocircuit level with preserved thalamocortical network function for CMD patients with subcortical lesions. Amongst patients with bilateral cortical lesions preserved cortico-cortical network function is associated with CMD detection. These data may allow screening for CMD based on widely available structural MRI and resting EEG.
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Lesões Encefálicas , Humanos , Lesões Encefálicas/complicações , Imageamento por Ressonância Magnética , Prosencéfalo , Imagem de Difusão por Ressonância Magnética , Estado de ConsciênciaRESUMO
The mammalian sperm midpiece has a unique double-helical structure called the mitochondrial sheath that wraps tightly around the axoneme. Despite the remarkable organization of the mitochondrial sheath, the molecular mechanisms involved in mitochondrial sheath formation are unclear. In the process of screening testis-enriched genes for functions in mice, we identified armadillo repeat-containing 12 (ARMC12) as an essential protein for mitochondrial sheath formation. Here, we engineered Armc12-null mice, FLAG-tagged Armc12 knock-in mice, and TBC1 domain family member 21 (Tbc1d21)-null mice to define the functions of ARMC12 in mitochondrial sheath formation in vivo. We discovered that absence of ARMC12 causes abnormal mitochondrial coiling along the flagellum, resulting in reduced sperm motility and male sterility. During spermiogenesis, sperm mitochondria in Armc12-null mice cannot elongate properly at the mitochondrial interlocking step which disrupts abnormal mitochondrial coiling. ARMC12 is a mitochondrial peripheral membrane protein and functions as an adherence factor between mitochondria in cultured cells. ARMC12 in testicular germ cells interacts with mitochondrial proteins MIC60, VDAC2, and VDAC3 as well as TBC1D21 and GK2, which are required for mitochondrial sheath formation. We also observed that TBC1D21 is essential for the interaction between ARMC12 and VDAC proteins in vivo. These results indicate that ARMC12 uses integral mitochondrial membrane proteins VDAC2 and VDAC3 as scaffolds to link mitochondria and works cooperatively with TBC1D21. Thus, our studies have revealed that ARMC12 regulates spatiotemporal mitochondrial dynamics to form the mitochondrial sheath through cooperative interactions with several proteins on the sperm mitochondrial surface.
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Proteínas do Domínio Armadillo/genética , Proteínas Ativadoras de GTPase/genética , Infertilidade Masculina/genética , Proteínas dos Microfilamentos/genética , Dinâmica Mitocondrial/genética , Animais , Axonema/genética , Humanos , Infertilidade Masculina/patologia , Masculino , Camundongos , Camundongos Knockout , Proteínas de Transporte da Membrana Mitocondrial/genética , Motilidade dos Espermatozoides/genética , Cauda do Espermatozoide/patologia , Cauda do Espermatozoide/ultraestrutura , Espermátides/metabolismo , Espermatogênese/genética , Espermatozoides/patologia , Espermatozoides/ultraestrutura , Testículo/metabolismo , Canal de Ânion 2 Dependente de Voltagem/genética , Canais de Ânion Dependentes de Voltagem/genéticaRESUMO
BACKGROUND: Viscoelastic hemostatic assays (VHAs) provide more comprehensive assessments of coagulation compared with conventional coagulation assays. Although VHAs have enabled guided hemorrhage control therapies, improving clinical outcomes in life-threatening hemorrhage, the role of VHAs in intracerebral hemorrhage (ICH) is unclear. If VHAs can identify coagulation abnormalities relevant for ICH outcomes, this would support the need to investigate the role of VHAs in ICH treatment paradigms. Thus, we investigated whether VHA assessments of coagulation relate to long-term ICH outcomes. METHODS: Patients with spontaneous ICH enrolled into a single-center cohort study receiving admission Rotational Thromboelastometry (ROTEM) VHA testing between 2013 and 2020 were assessed. Patients with previous anticoagulant use or coagulopathy on conventional coagulation assays were excluded. Primary ROTEM exposure variables were coagulation kinetics and clot strength assessments. Poor long-term outcome was defined as modified Rankin Scale ≥ 4 at 6 months. Logistic regression analyses assessed associations of ROTEM parameters with clinical outcomes after adjusting for ICH severity and hemoglobin concentration. RESULTS: Of 44 patients analyzed, the mean age was 64 years, 57% were female, and the median ICH volume was 23 mL. Poor 6-month outcome was seen in 64% of patients. In our multivariable regression models, slower, prolonged coagulation kinetics (adjusted odds ratio for every second increase in clot formation time 1.04, 95% confidence interval 1.00-1.09, p = 0.04) and weaker clot strength (adjusted odds ratio for every millimeter increase of maximum clot firmness 0.84, 95% confidence interval 0.71-0.99, p = 0.03) were separately associated with poor long-term outcomes. CONCLUSIONS: Slower, prolonged coagulation kinetics and weaker clot strength on admission VHA ROTEM testing, not attributable to anticoagulant use, were associated with poor long-term outcomes after ICH. Further work is needed to clarify the generalizability and the underlying mechanisms of these VHA findings to assess whether VHA-guided treatments should be incorporated into ICH care.
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BACKGROUND: Brain activation to motor commands is seen in 15% of clinically unresponsive patients with acute brain injury. This state called cognitive motor dissociation (CMD) is detectable by electroencephalogram (EEG) or functional magnetic resonance imaging, predicts long-term recovery, and is recommended by recent guidelines to support prognostication. However, false negative CMD results are a particular concern, and occult aphasia in clinically unresponsive patients may be a major factor. This study aimed to quantify the impact of aphasia on CMD testing. METHODS: We prospectively studied 61 intensive care unit patients admitted with acute primary intracerebral hemorrhage (ICH) who had behavioral evidence of command following or were able to mimic motor commands. All patients underwent an EEG-based motor command paradigm used to detect CMD and comprehensive aphasia assessments. Logistic regression was used to identify predictors of brain activation, including aphasia types and associations with recovery of independence (Glasgow Outcome Scale-Extended score ≥ 4). RESULTS: Of 61 patients, 50 completed aphasia and the EEG-based motor command paradigm. A total of 72% (n = 36) were diagnosed with aphasia. Patients with impaired comprehension (i.e., receptive or global aphasia) were less likely to show brain activation than those with intact comprehension (odds ratio [OR] 0.23 [95% confidence interval 0.05-0.89], p = 0.04). Brain activation was independently associated with Glasgow Outcome Scale-Extended ≥ 4 by 12 months (OR 2.4 [95% confidence interval 1.2-5.0], p = 0.01) accounting for the Functional Outcome in Patients with Primary ICH score (OR1.3 [95% confidence interval 1.0-1.8], p = 0.01). CONCLUSIONS: Brain activation to motor commands is four times less likely for patients with primary ICH with impaired comprehension. False negative results due to occult receptive aphasia need to be considered when interpreting CMD testing. Early detection of brain activation may help predict long-term recovery in conscious patients with ICH.
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BACKGROUND: Numerous trials have addressed intracranial pressure (ICP) management in neurocritical care. However, identifying its harmful thresholds and controlling ICP remain challenging in terms of improving outcomes. Evidence suggests that an individualized approach is necessary for establishing tolerance limits for ICP, incorporating factors such as ICP waveform (ICPW) or pulse morphology along with additional data provided by other invasive (e.g., brain oximetry) and noninvasive monitoring (NIM) methods (e.g., transcranial Doppler, optic nerve sheath diameter ultrasound, and pupillometry). This study aims to assess current ICP monitoring practices among experienced clinicians and explore whether guidelines should incorporate ancillary parameters from NIM and ICPW in future updates. METHODS: We conducted a survey among experienced professionals involved in researching and managing patients with severe injury across low-middle-income countries (LMICs) and high-income countries (HICs). We sought their insights on ICP monitoring, particularly focusing on the impact of NIM and ICPW in various clinical scenarios. RESULTS: From October to December 2023, 109 professionals from the Americas and Europe participated in the survey, evenly distributed between LMIC and HIC. When ICP ranged from 22 to 25 mm Hg, 62.3% of respondents were open to considering additional information, such as ICPW and other monitoring techniques, before adjusting therapy intensity levels. Moreover, 77% of respondents were inclined to reassess patients with ICP in the 18-22 mm Hg range, potentially escalating therapy intensity levels with the support of ICPW and NIM. Differences emerged between LMIC and HIC participants, with more LMIC respondents preferring arterial blood pressure transducer leveling at the heart and endorsing the use of NIM techniques and ICPW as ancillary information. CONCLUSIONS: Experienced clinicians tend to personalize ICP management, emphasizing the importance of considering various monitoring techniques. ICPW and noninvasive techniques, particularly in LMIC settings, warrant further exploration and could potentially enhance individualized patient care. The study suggests updating guidelines to include these additional components for a more personalized approach to ICP management.
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BACKGROUND AND PURPOSE: Non-O blood types are known to be associated with thromboembolic complications (TECs) in population-based studies. TECs are known drivers of morbidity and mortality in intracerebral hemorrhage (ICH) patients, yet the relationships of blood type on TECs in this patient population are unknown. We sought to explore the relationships between ABO blood type and TECs in ICH patients. METHODS: Consecutive adult ICH patients enrolled into a prospective observational cohort study with available ABO blood type data were analyzed. Patients with cancer history, prior thromboembolism, and baseline laboratory evidence of coagulopathy were excluded. The primary exposure variable was blood type (non-O versus O). The primary outcome was composite TEC, defined as pulmonary embolism, deep venous thrombosis, ischemic stroke or myocardial infarction, during the hospital stay. Relationships between blood type, TECs and clinical outcomes were separately assessed using logistic regression models after adjusting for sex, ethnicity and ICH score. RESULTS: Of 301 ICH patients included for analysis, 44% were non-O blood type. Non-O blood type was associated with higher admission GCS and lower ICH score on baseline comparisons. We identified TECs in 11.6% of our overall patient cohort. . Although TECs were identified in 9.9% of non-O blood type patients compared to 13.0% in O blood type patients, we did not identify a significant relationship of non-O blood type with TECs (adjusted OR=0.776, 95%CI: 0.348-1.733, p=0.537). The prevalence of specific TECs were also comparable in unadjusted and adjusted analyses between the two cohorts. In additional analyses, we identified that TECs were associated with poor 90-day mRS (adjusted OR=3.452, 95% CI: 1.001-11.903, p=0.050). We did not identify relationships between ABO blood type and poor 90-day mRS (adjusted OR=0.994, 95% CI:0.465-2.128, p=0.988). CONCLUSIONS: We identified that TECs were associated with worse ICH outcomes. However, we did not identify relationships in ABO blood type and TECs. Further work is required to assess best diagnostic and prophylactic and treatment strategies for TECs to improve ICH outcomes.
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Embolia Pulmonar , Tromboembolia , Adulto , Humanos , Estudos Prospectivos , Hemorragia Cerebral/diagnóstico , Tromboembolia/diagnóstico , Tromboembolia/epidemiologia , Tromboembolia/etiologia , Modelos Logísticos , Embolia Pulmonar/complicaçõesRESUMO
BACKGROUND: Targeting a cerebral perfusion pressure optimal for cerebral autoregulation (CPPopt) has been gaining more attention to prevent secondary damage after acute neurological injury. Brain tissue oxygenation (PbtO2) can identify insufficient cerebral blood flow and secondary brain injury. Defining the relationship between CPPopt and PbtO2 after aneurysmal subarachnoid hemorrhage may result in (1) mechanistic insights into whether and how CPPopt-based strategies might be beneficial and (2) establishing support for the use of PbtO2 as an adjunctive monitor for adequate or optimal local perfusion. METHODS: We performed a retrospective analysis of a prospectively collected 2-center dataset of patients with aneurysmal subarachnoid hemorrhage with or without later diagnosis of delayed cerebral ischemia (DCI). CPPopt was calculated as the cerebral perfusion pressure (CPP) value corresponding to the lowest pressure reactivity index (moving correlation coefficient of mean arterial and intracranial pressure). The relationship of (hourly) deltaCPP (CPP-CPPopt) and PbtO2 was investigated using natural spline regression analysis. Data after DCI diagnosis were excluded. Brain tissue hypoxia was defined as PbtO2 <20 mmHg. RESULTS: One hundred thirty-one patients were included with a median of 44.0 (interquartile range, 20.8-78.3) hourly CPPopt/PbtO2 datapoints. The regression plot revealed a nonlinear relationship between PbtO2 and deltaCPP (P<0.001) with PbtO2 decrease with deltaCPP <0 mmHg and stable PbtO2 with deltaCPP ≥0mmHg, although there was substantial individual variation. Brain tissue hypoxia (34.6% of all measurements) was more frequent with deltaCPP <0 mmHg. These dynamics were similar in patients with or without DCI. CONCLUSIONS: We found a nonlinear relationship between PbtO2 and deviation of patients' CPP from CPPopt in aneurysmal subarachnoid hemorrhage patients in the pre-DCI period. CPP values below calculated CPPopt were associated with lower PbtO2. Nevertheless, the nature of PbtO2 measurements is complex, and the variability is high. Combined multimodality monitoring with CPP/CPPopt and PbtO2 should be recommended to redefine individual pressure targets (CPP/CPPopt) and retain the option to detect local perfusion deficits during DCI (PbtO2), which cannot be fulfilled by both measurements interchangeably.
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Lesões Encefálicas Traumáticas , Isquemia Encefálica , Hemorragia Subaracnóidea , Humanos , Estudos Retrospectivos , Oxigênio , Encéfalo/diagnóstico por imagem , Infarto Cerebral , Pressão Intracraniana , Circulação Cerebrovascular/fisiologia , Hipóxia , Lesões Encefálicas Traumáticas/diagnósticoRESUMO
Subarachnoid haemorrhage (SAH) is the third most common subtype of stroke. Incidence has decreased over past decades, possibly in part related to lifestyle changes such as smoking cessation and management of hypertension. Approximately a quarter of patients with SAH die before hospital admission; overall outcomes are improved in those admitted to hospital, but with elevated risk of long-term neuropsychiatric sequelae such as depression. The disease continues to have a major public health impact as the mean age of onset is in the mid-fifties, leading to many years of reduced quality of life. The clinical presentation varies, but severe, sudden onset of headache is the most common symptom, variably associated with meningismus, transient or prolonged unconsciousness, and focal neurological deficits including cranial nerve palsies and paresis. Diagnosis is made by CT scan of the head possibly followed by lumbar puncture. Aneurysms are commonly the underlying vascular cause of spontaneous SAH and are diagnosed by angiography. Emergent therapeutic interventions are focused on decreasing the risk of rebleeding (ie, preventing hypertension and correcting coagulopathies) and, most crucially, early aneurysm treatment using coil embolisation or clipping. Management of the disease is best delivered in specialised intensive care units and high-volume centres by a multidisciplinary team. Increasingly, early brain injury presenting as global cerebral oedema is recognised as a potential treatment target but, currently, disease management is largely focused on addressing secondary complications such as hydrocephalus, delayed cerebral ischaemia related to microvascular dysfunction and large vessel vasospasm, and medical complications such as stunned myocardium and hospital acquired infections.
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Isquemia Encefálica , Hipertensão , Aneurisma Intracraniano , Hemorragia Subaracnóidea , Isquemia Encefálica/complicações , Humanos , Hipertensão/complicações , Aneurisma Intracraniano/complicações , Qualidade de Vida , Hemorragia Subaracnóidea/diagnóstico , Hemorragia Subaracnóidea/etiologia , Hemorragia Subaracnóidea/terapiaRESUMO
Previously, we found that dysfunctional natural killer (NK) cells with low interferon gamma (IFN-γ) were restored in acute myeloid leukemia (AML) by the FLT4 antagonist MAZ51. Here, we developed 12 peptides targeting FLT4 for clinical application and examined whether they restored the frequency of lymphocytes, especially T cells and NK cells, and high IFN-γ expression, as MAZ51 treatment did in our previous study. Although clinical data from using peptides are currently available, peptides targeting FLT4 to modulate immune cells have not been fully elucidated. In this study, we focus on novel peptide 4 (P4) from the intracellular domain of FLT4 because it had dominant negative activity. Similar to MAZ51, high IFN-γ levels were expressed in AML-mononuclear cells exposed to P4. Additionally, T and NK cell levels were restored, as were high IFN-γ levels, in a leukemic environment when P4 was treated. Interestingly, the regulatory T cells were significantly decreased by P4, implying the role of peptide in tumor niche. Overall, we demonstrated the therapeutic value of functionally modulating lymphocytes using a peptide targeting FLT4 and proposed the development of advanced therapeutic approaches against AML by using immune cells.
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Leucemia Mieloide Aguda , Humanos , Leucemia Mieloide Aguda/tratamento farmacológico , Células Matadoras Naturais , Interferon gama/metabolismo , Receptor 3 de Fatores de Crescimento do Endotélio VascularRESUMO
Flexible lithium-ion batteries (LIBs) have attracted significant attention owing to their ever-increasing use in flexible and wearable electronic devices. However, the practical application of flexible LIBs in devices has been plagued by the challenge of simultaneously achieving high energy density and high flexibility. Herein, a hierarchical 3D electrode (H3DE) is introduced with high mass loading that can construct highly flexible LIBs with ultrahigh energy density. The H3DE features a bicontinuous structure and the active materials along with conductive agents are uniformly distributed on the 3D framework regardless of the active material type. The bicontinuous electrode/electrolyte integration enables a rapid ion/electron transport, thereby improving the redox kinetics and lowering the internal cell resistance. Moreover, the H3DE exhibits exceptional structural integrity and flexibility during repeated mechanical deformations. Benefiting from the remarkable physicochemical properties, pouch-type flexible LIBs using H3DE demonstrate stable cycling under various bending states, achieving a record-high energy density (438.6 Wh kg-1 and 20.4 mWh cm-2 ), and areal capacity (5.6 mAh cm-2 ), outperforming all previously reported flexible LIBs. This study provides a feasible solution for the preparation of high-energy-density flexible LIBs for various energy storage devices.
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OBJECTIVES: To address areas in which there is no consensus for the technologies, effort, and training necessary to integrate and interpret information from multimodality neuromonitoring (MNM). DESIGN: A three-round Delphi consensus process. SETTING: Electronic surveys and virtual meeting. SUBJECTS: Participants with broad MNM expertise from adult and pediatric intensive care backgrounds. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Two rounds of surveys were completed followed by a virtual meeting to resolve areas without consensus and a final survey to conclude the Delphi process. With 35 participants consensus was achieved on 49% statements concerning MNM. Neurologic impairment and the potential for MNM to guide management were important clinical considerations. Experts reached consensus for the use of MNM-both invasive and noninvasive-for patients in coma with traumatic brain injury, aneurysmal subarachnoid hemorrhage, and intracranial hemorrhage. There was consensus that effort to integrate and interpret MNM requires time independent of daily clinical duties, along with specific skills and expertise. Consensus was reached that training and educational platforms are necessary to develop this expertise and to provide clinical correlation. CONCLUSIONS: We provide expert consensus in the clinical considerations, minimum necessary technologies, implementation, and training/education to provide practice standards for the use of MNM to individualize clinical care.
Assuntos
Competência Clínica , Adulto , Criança , Humanos , Consenso , Técnica Delphi , Inquéritos e Questionários , Padrões de ReferênciaRESUMO
OBJECTIVES: Low hemoglobin concentration impairs clinical hemostasis across several diseases. It is unclear whether hemoglobin impacts laboratory functional coagulation assessments. We evaluated the relationship of hemoglobin concentration on viscoelastic hemostatic assays in intracerebral hemorrhage (ICH) and perioperative patients admitted to an ICU. DESIGN: Observational cohort study and separate in vitro laboratory study. SETTING: Multicenter tertiary referral ICUs. PATIENTS: Two acute ICH cohorts receiving distinct testing modalities: rotational thromboelastometry (ROTEM) and thromboelastography (TEG), and a third surgical ICU cohort receiving ROTEM were evaluated to assess the generalizability of findings across disease processes and testing platforms. A separate in vitro ROTEM laboratory study was performed utilizing ICH patient blood samples. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: Relationships between baseline hemoglobin and ROTEM/TEG results were separately assessed across patient cohorts using Spearman correlations and linear regression models. A separate in vitro study assessed ROTEM tracing changes after serial hemoglobin modifications from ICH patient blood samples. In both our ROTEM (n = 34) and TEG (n = 239) ICH cohorts, hemoglobin concentrations directly correlated with coagulation kinetics (ROTEM r: 0.46; p = 0.01; TEG r: 0.49; p < 0.0001) and inversely correlated with clot strength (ROTEM r: -0.52, p = 0.002; TEG r: -0.40, p < 0.0001). Similar relationships were identified in perioperative ICU admitted patients (n = 121). We continued to identify these relationships in linear regression models. When manipulating ICH patient blood samples to achieve lower hemoglobin concentrations in vitro, we similarly identified that lower hemoglobin concentrations resulted in progressively faster coagulation kinetics and greater clot strength on ROTEM tracings. CONCLUSIONS: Lower hemoglobin concentrations have a consistent, measurable impact on ROTEM/TEG testing in ICU admitted patients, which appear to be artifactual. It is possible that patients with low hemoglobin may appear to have normal viscoelastic parameters when, in fact, they have a mild hypocoagulable state. Further work is required to determine if these tests should be corrected for a patient's hemoglobin concentration.