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The microscopic origin of high-temperature superconductivity in cuprates remains unknown. It is widely believed that substantial progress could be achieved by better understanding of the pseudogap phase, a normal non-superconducting state of cuprates1,2. In particular, a central issue is whether the pseudogap could originate from strong pairing fluctuations3. Unitary Fermi gases4,5, in which the pseudogap-if it exists-necessarily arises from many-body pairing, offer ideal quantum simulators to address this question. Here we report the observation of a pair-fluctuation-driven pseudogap in homogeneous unitary Fermi gases of lithium-6 atoms, by precisely measuring the fermion spectral function through momentum-resolved microwave spectroscopy and without spurious effects from final-state interactions. The temperature dependence of the pairing gap, inverse pair lifetime and single-particle scattering rate are quantitatively determined by analysing the spectra. We find a large pseudogap above the superfluid transition temperature. The inverse pair lifetime exhibits a thermally activated exponential behaviour, uncovering the microscopic virtual pair breaking and recombination mechanism. The obtained large, temperature-independent single-particle scattering rate is comparable with that set by the Planckian limit6. Our findings quantitatively characterize the pseudogap in strongly interacting Fermi gases and they lend support for the role of preformed pairing as a precursor to superfluidity.
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The hexosamine biosynthetic pathway (HBP) generates uridine diphosphate N-acetylglucosamine (UDP-GlcNAc) for glycan synthesis and O-linked GlcNAc (O-GlcNAc) protein modifications. Despite the established role of the HBP in metabolism and multiple diseases, regulation of the HBP remains largely undefined. Here, we show that spliced X-box binding protein 1 (Xbp1s), the most conserved signal transducer of the unfolded protein response (UPR), is a direct transcriptional activator of the HBP. We demonstrate that the UPR triggers HBP activation via Xbp1s-dependent transcription of genes coding for key, rate-limiting enzymes. We further establish that this previously unrecognized UPR-HBP axis is triggered in a variety of stress conditions. Finally, we demonstrate a physiologic role for the UPR-HBP axis by showing that acute stimulation of Xbp1s in heart by ischemia/reperfusion confers robust cardioprotection in part through induction of the HBP. Collectively, these studies reveal that Xbp1s couples the UPR to the HBP to protect cells under stress.
Assuntos
Vias Biossintéticas , Proteínas de Ligação a DNA/metabolismo , Hexosaminas/metabolismo , Fatores de Transcrição/metabolismo , Resposta a Proteínas não Dobradas , Animais , Glutamina-Frutose-6-Fosfato Transaminase (Isomerizante) , Humanos , Masculino , Camundongos , Camundongos Transgênicos , Isquemia Miocárdica/metabolismo , Traumatismo por Reperfusão Miocárdica/metabolismo , Miócitos Cardíacos/metabolismo , Transferases de Grupos Nitrogenados/genética , Fatores de Transcrição de Fator Regulador X , Proteína 1 de Ligação a X-BoxRESUMO
Senescence and altered differentiation potential of bone marrow stromal cells (BMSCs) lead to age-related bone loss. As an important posttranscriptional regulatory pathway, alternative splicing (AS) regulates the diversity of gene expression and has been linked to induction of cellular senescence. However, the role of splicing factors in BMSCs during aging remains poorly defined. Herein, we found that the expression of the splicing factor Y-box binding protein 1 (YBX1) in BMSCs decreased with aging in mice and humans. YBX1 deficiency resulted in mis-splicing in genes linked to BMSC osteogenic differentiation and senescence, such as Fn1, Nrp2, Sirt2, Sp7, and Spp1, thus contributing to BMSC senescence and differentiation shift during aging. Deletion of Ybx1 in BMSCs accelerated bone loss in mice, while its overexpression stimulated bone formation. Finally, we identified a small compound, sciadopitysin, which attenuated the degradation of YBX1 and bone loss in old mice. Our study demonstrated that YBX1 governs cell fate of BMSCs via fine control of RNA splicing and provides a potential therapeutic target for age-related osteoporosis.
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Células-Tronco Mesenquimais , Osteoporose , Humanos , Camundongos , Animais , Osteogênese/genética , Envelhecimento/metabolismo , Senescência Celular , Diferenciação Celular/genética , Osteoporose/metabolismo , Células da Medula Óssea , Proteína 1 de Ligação a Y-Box/metabolismoRESUMO
BACKGROUND: Recent interest in understanding cardiomyocyte cell cycle has been driven by potential therapeutic applications in cardiomyopathy. However, despite recent advances, cardiomyocyte mitosis remains a poorly understood process. For example, it is unclear how sarcomeres are disassembled during mitosis to allow the abscission of daughter cardiomyocytes. METHODS: Here, we use a proteomics screen to identify adducin, an actin capping protein previously not studied in cardiomyocytes, as a regulator of sarcomere disassembly. We generated many adeno-associated viruses and cardiomyocyte-specific genetic gain-of-function models to examine the role of adducin in neonatal and adult cardiomyocytes in vitro and in vivo. RESULTS: We identify adducin as a regulator of sarcomere disassembly during mammalian cardiomyocyte mitosis. α/γ-adducins are selectively expressed in neonatal mitotic cardiomyocytes, and their levels decline precipitously thereafter. Cardiomyocyte-specific overexpression of various splice isoforms and phospho-isoforms of α-adducin in vitro and in vivo identified Thr445/Thr480 phosphorylation of a short isoform of α-adducin as a potent inducer of neonatal cardiomyocyte sarcomere disassembly. Concomitant overexpression of this α-adducin variant along with γ-adducin resulted in stabilization of the adducin complex and persistent sarcomere disassembly in adult mice, which is mediated by interaction with α-actinin. CONCLUSIONS: These results highlight an important mechanism for coordinating cytoskeletal morphological changes during cardiomyocyte mitosis.
Assuntos
Proteínas de Ligação a Calmodulina , Mitose , Miócitos Cardíacos , Sarcômeros , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/citologia , Animais , Sarcômeros/metabolismo , Proteínas de Ligação a Calmodulina/metabolismo , Proteínas de Ligação a Calmodulina/genética , Camundongos , Fosforilação , Animais Recém-Nascidos , Células Cultivadas , Ratos , HumanosRESUMO
BACKGROUND: Cardiomyocyte growth is coupled with active protein synthesis, which is one of the basic biological processes in living cells. However, it is unclear whether the unfolded protein response transducers and effectors directly take part in the control of protein synthesis. The connection between critical functions of the unfolded protein response in cellular physiology and requirements of multiple processes for cell growth prompted us to investigate the role of the unfolded protein response in cell growth and underlying molecular mechanisms. METHODS: Cardiomyocyte-specific inositol-requiring enzyme 1α (IRE1α) knockout and overexpression mouse models were generated to explore its function in vivo. Neonatal rat ventricular myocytes were isolated and cultured to evaluate the role of IRE1α in cardiomyocyte growth in vitro. Mass spectrometry was conducted to identify novel interacting proteins of IRE1α. Ribosome sequencing and polysome profiling were performed to determine the molecular basis for the function of IRE1α in translational control. RESULTS: We show that IRE1α is required for cell growth in neonatal rat ventricular myocytes under prohypertrophy treatment and in HEK293 cells in response to serum stimulation. At the molecular level, IRE1α directly interacts with eIF4G and eIF3, 2 critical components of the translation initiation complex. We demonstrate that IRE1α facilitates the formation of the translation initiation complex around the endoplasmic reticulum and preferentially initiates the translation of transcripts with 5' terminal oligopyrimidine motifs. We then reveal that IRE1α plays an important role in determining the selectivity and translation of these transcripts. We next show that IRE1α stimulates the translation of epidermal growth factor receptor through an unannotated terminal oligopyrimidine motif in its 5' untranslated region. We further demonstrate a physiological role of IRE1α-governed protein translation by showing that IRE1α is essential for cardiomyocyte growth and cardiac functional maintenance under hemodynamic stress in vivo. CONCLUSIONS: These studies suggest a noncanonical, essential role of IRE1α in orchestrating protein synthesis, which may have important implications in cardiac hypertrophy in response to pressure overload and general cell growth under other physiological and pathological conditions.
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Endorribonucleases , Miócitos Cardíacos , Proteínas Serina-Treonina Quinases , Animais , Miócitos Cardíacos/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Proteínas Serina-Treonina Quinases/genética , Endorribonucleases/metabolismo , Endorribonucleases/genética , Humanos , Ratos , Células HEK293 , Biossíntese de Proteínas , Camundongos , Camundongos Knockout , Cardiomegalia/metabolismo , Cardiomegalia/genética , Cardiomegalia/patologia , Resposta a Proteínas não Dobradas , Células Cultivadas , Animais Recém-Nascidos , Fator de Iniciação Eucariótico 4G/metabolismo , Fator de Iniciação Eucariótico 4G/genética , Ratos Sprague-Dawley , Complexos MultienzimáticosRESUMO
Heart failure with preserved ejection fraction (HFpEF) is a common syndrome with high morbidity and mortality for which there are no evidence-based therapies. Here we report that concomitant metabolic and hypertensive stress in mice-elicited by a combination of high-fat diet and inhibition of constitutive nitric oxide synthase using Nω-nitro-L-arginine methyl ester (L-NAME)-recapitulates the numerous systemic and cardiovascular features of HFpEF in humans. Expression of one of the unfolded protein response effectors, the spliced form of X-box-binding protein 1 (XBP1s), was reduced in the myocardium of our rodent model and in humans with HFpEF. Mechanistically, the decrease in XBP1s resulted from increased activity of inducible nitric oxide synthase (iNOS) and S-nitrosylation of the endonuclease inositol-requiring protein 1α (IRE1α), culminating in defective XBP1 splicing. Pharmacological or genetic suppression of iNOS, or cardiomyocyte-restricted overexpression of XBP1s, each ameliorated the HFpEF phenotype. We report that iNOS-driven dysregulation of the IRE1α-XBP1 pathway is a crucial mechanism of cardiomyocyte dysfunction in HFpEF.
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Insuficiência Cardíaca/metabolismo , Insuficiência Cardíaca/fisiopatologia , Estresse Nitrosativo , Volume Sistólico , Animais , Dieta Hiperlipídica/efeitos adversos , Modelos Animais de Doenças , Endorribonucleases/metabolismo , Insuficiência Cardíaca/prevenção & controle , Humanos , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Miócitos Cardíacos/enzimologia , Miócitos Cardíacos/metabolismo , Miócitos Cardíacos/patologia , NG-Nitroarginina Metil Éster/farmacologia , Óxido Nítrico Sintase Tipo II/antagonistas & inibidores , Óxido Nítrico Sintase Tipo II/deficiência , Óxido Nítrico Sintase Tipo II/genética , Óxido Nítrico Sintase Tipo II/metabolismo , Fenótipo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Proteína 1 de Ligação a X-Box/genética , Proteína 1 de Ligação a X-Box/metabolismoRESUMO
Amino acids are essential for cell growth and metabolism. Amino acid and growth factor signaling pathways coordinately regulate the mechanistic target of rapamycin complex 1 (mTORC1) kinase in cell growth and organ development. While major components of amino acid signaling mechanisms have been identified, their biological functions in organ development are unclear. We aimed to understand the functions of the critically positioned amino acid signaling complex GAP activity towards Rags 2 (GATOR2) in brain development. GATOR2 mediates amino acid signaling to mTORC1 by directly linking the amino acid sensors for arginine and leucine to downstream signaling complexes. Now, we report a role of GATOR2 in oligodendrocyte myelination in postnatal brain development. We show that the disruption of GATOR2 complex by genetic deletion of meiosis regulator for oocyte development (Mios, encoding a component of GATOR2) selectively impairs the formation of myelinating oligodendrocytes, thus brain myelination, without apparent effects on the formation of neurons and astrocytes. The loss of Mios impairs cell cycle progression of oligodendrocyte precursor cells, leading to their reduced proliferation and differentiation. Mios deletion manifests a cell type-dependent effect on mTORC1 in the brain, with oligodendroglial mTORC1 selectively affected. However, the role of Mios/GATOR2 in oligodendrocyte formation and myelination involves mTORC1-independent function. This study suggests that GATOR2 coordinates amino acid and growth factor signaling to regulate oligodendrocyte myelination.
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Aminoácidos/metabolismo , Encéfalo/metabolismo , Complexos Multiproteicos/metabolismo , Bainha de Mielina/metabolismo , Transdução de Sinais , Animais , Diferenciação Celular , Linhagem da Célula , Proliferação de Células , Deleção de Genes , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos Knockout , Modelos Biológicos , Células-Tronco Neurais/metabolismo , Oligodendroglia/citologia , Oligodendroglia/metabolismo , TransgenesRESUMO
Walnut (Juglans) species are economically important hardwood trees cultivated worldwide for both edible nuts and high-quality wood. Broad-scale assessments of species diversity, evolutionary history, and domestication are needed to improve walnut breeding. In this study, we sequenced 309 walnut accessions from around the world, including 55 Juglans relatives, 98 wild Persian walnuts (J. regia), 70 J. regia landraces, and 86 J. regia cultivars. The phylogenetic tree indicated that J. regia samples (section Dioscaryon) were monophyletic within Juglans. The core areas of genetic diversity of J. regia germplasm were southwestern China and southern Asia near the Qinghai-Tibet Plateau and the Himalayas, and the uplift of the Himalayas was speculated to be the main factor leading to the current population dynamics of Persian walnut. The pattern of genomic variation in terms of nucleotide diversity, linkage disequilibrium, single nucleotide polymorphisms, and insertions/deletions revealed the domestication and selection footprints in Persian walnut. Selective sweep analysis, GWAS, and expression analysis further identified two transcription factors, JrbHLH and JrMYB6, that influence the thickness of the nut diaphragm as loci under selection during domestication. Our results elucidate the domestication and selection footprints in Persian walnuts and provide a valuable resource for the genomics-assisted breeding of this important crop.
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Juglans , Juglans/genética , Filogenia , Ásia Meridional , China , GenômicaRESUMO
BACKGROUND: Cellular redox control is maintained by generation of reactive oxygen/nitrogen species balanced by activation of antioxidative pathways. Disruption of redox balance leads to oxidative stress, a central causative event in numerous diseases including heart failure. Redox control in the heart exposed to hemodynamic stress, however, remains to be fully elucidated. METHODS: Pressure overload was triggered by transverse aortic constriction in mice. Transcriptomic and metabolomic regulations were evaluated by RNA-sequencing and metabolomics, respectively. Stable isotope tracer labeling experiments were conducted to determine metabolic flux in vitro. Neonatal rat ventricular myocytes and H9c2 cells were used to examine molecular mechanisms. RESULTS: We show that production of cardiomyocyte NADPH, a key factor in redox regulation, is decreased in pressure overload-induced heart failure. As a consequence, the level of reduced glutathione is downregulated, a change associated with fibrosis and cardiomyopathy. We report that the pentose phosphate pathway and mitochondrial serine/glycine/folate metabolic signaling, 2 NADPH-generating pathways in the cytosol and mitochondria, respectively, are induced by transverse aortic constriction. We identify ATF4 (activating transcription factor 4) as an upstream transcription factor controlling the expression of multiple enzymes in these 2 pathways. Consistently, joint pathway analysis of transcriptomic and metabolomic data reveal that ATF4 preferably controls oxidative stress and redox-related pathways. Overexpression of ATF4 in neonatal rat ventricular myocytes increases NADPH-producing enzymes' whereas silencing of ATF4 decreases their expression. Further, stable isotope tracer experiments reveal that ATF4 overexpression augments metabolic flux within these 2 pathways. In vivo, cardiomyocyte-specific deletion of ATF4 exacerbates cardiomyopathy in the setting of transverse aortic constriction and accelerates heart failure development, attributable, at least in part, to an inability to increase the expression of NADPH-generating enzymes. CONCLUSIONS: Our findings reveal that ATF4 plays a critical role in the heart under conditions of hemodynamic stress by governing both cytosolic and mitochondrial production of NADPH.
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Insuficiência Cardíaca , Estresse Oxidativo , Fator 4 Ativador da Transcrição/genética , Fator 4 Ativador da Transcrição/metabolismo , Animais , Insuficiência Cardíaca/metabolismo , Camundongos , Miócitos Cardíacos/metabolismo , NADP/metabolismo , Estresse Oxidativo/fisiologia , Ratos , Espécies Reativas de Oxigênio/metabolismoRESUMO
A straightforward methodology for the assembly of polysubstituted naphthalenes from ortho-alkynyl benzyl alcohols, enabled by using catalytic amounts of Tf2O, has been developed. This transformation not only features transition-metal free and without using other bases and additives but also provides a new synthetic application for ortho-alkynyl benzyl alcohols, i.e., as C6 synthons for the construction of PAHs.
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Six new sesquiterpene quinone/hydroquinone meroterpenoids, arenarialins A-F (1-6), were isolated from the marine sponge Dysidea arenaria collected from the South China Sea. Their chemical structures and absolute configurations were determined by HRMS and NMR data analyses coupled with DP4+ and ECD calculations. Arenarialin A (1) features an unprecedented tetracyclic 6/6/5/6 carbon skeleton, whereas arenarialins B-D (2-4) possess two rare secomeroterpene scaffolds. Arenarialins A-F showed inhibitory activity on the production of inflammatory cytokines TNF-α and IL-6 in LPS-induced RAW264.7 macrophages with arenarialin D regulating the NF-κB/MAPK signaling pathway.
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Dysidea , Poríferos , Sesquiterpenos , Animais , Dysidea/química , Poríferos/química , Sesquiterpenos/farmacologia , Sesquiterpenos/química , Anti-Inflamatórios/farmacologia , NF-kappa B , Estrutura MolecularRESUMO
BACKGROUND Pyogenic spondylodiscitis is infection of the intervertebral disc or discs and the adjacent vertebrae. This retrospective study aimed to compare the effectiveness of percutaneous endoscopic lumbar debridement (PELD) versus posterior lumbar interbody fusion (PLIF) in 40 patients with pyogenic spondylodiscitis (PSD). MATERIAL AND METHODS Medical records of patients who underwent PELD (n=18) or PLIF (n=22) for PSD between 2018 and 2023 were reviewed. The recorded outcomes encompassed surgical duration, intraoperative blood loss, Oswestry Disability Index (ODI) measurements, Visual Analog Scale (VAS) assessments, C-reactive protein (CRP) levels, duration of hospitalization, erythrocyte sedimentation rate (ESR), American Spinal Injury Association (ASIA) grading, lumbar sagittal parameters, and the incidence of complications. RESULTS The PELD group had shorter surgical duration, less intraoperative blood loss, and shorter length of hospital stay compared to the PLIF group (P<0.01). At the last follow-up, both groups had significant improvement in ESR, CRP levels, and ASIA classification (P<0.001), but there was no significant difference between the 2 groups (P>0.05). The PELD group had lower ODI and VAS ratings at 1 month and 3 months, respectively (P<0.01). The PLIF group had significant improvements in intervertebral space height and lumbar lordosis angle (P<0.01). CONCLUSIONS Both PLIF and PELD surgical approaches demonstrate adequate clinical efficacy in the treatment of monosegmental PSD. PLIF can better ensure more spinal stability than PELD, but PELD offers advantages such as reduced minimal surgical trauma, shorter operative duration, and faster recovery after surgery.
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Desbridamento , Discite , Vértebras Lombares , Procedimentos Cirúrgicos Minimamente Invasivos , Fusão Vertebral , Humanos , Masculino , Feminino , Discite/cirurgia , Pessoa de Meia-Idade , Fusão Vertebral/métodos , Vértebras Lombares/cirurgia , Desbridamento/métodos , Estudos Retrospectivos , Resultado do Tratamento , Procedimentos Cirúrgicos Minimamente Invasivos/métodos , Idoso , Adulto , Endoscopia/métodos , Tempo de Internação , Duração da CirurgiaRESUMO
Relapse is a major challenge in treating opioid addiction, including oxycodone. During abstinence, oxycodone seeking progressively increases, a phenomenon termed incubation of oxycodone craving. We previously demonstrated a causal role of orbitofrontal cortex (OFC) in this incubation. Here, we studied the interaction between glutamatergic projections from OFC and dopamine 1-family receptor (D1R) signaling in dorsal striatum (DS) in this incubation in male rats. We first examined the causal role of D1R signalling in DS in incubated oxycodone seeking. Next, we combined fluorescence-conjugated cholera toxin subunit B (CTb-555, a retrograde tracer) with Fos (a neuronal activity marker) to assess whether the activation of OFCâDS projections was associated with incubated oxycodone seeking. We then used a pharmacological asymmetrical disconnection procedure to examine the role of the interaction between projections from OFC and D1R signalling in DS in incubated oxycodone seeking. We also tested the effect of unilateral pharmacological inactivation of OFC or unilateral D1R blockade of DS on incubated oxycodone seeking. Finally, we assessed whether contralateral disconnection of OFCâDS projections impacted non-incubated oxycodone seeking on abstinence day 1. We found that D1R blockade in DS decreased incubated oxycodone seeking and OFCâDS projections were activated during incubated oxycodone seeking. Moreover, anatomical disconnection of OFCâDS projections, but not unilateral inactivation of OFC or unilateral D1R blockade in DS, decreased incubated oxycodone seeking. Lastly, contralateral disconnection of OFCâDS projections had no effect on oxycodone seeking on abstinence day 1. Together, these results demonstrated a causal role of OFCâDS projections in incubation of oxycodone craving.
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Corpo Estriado , Fissura , Comportamento de Procura de Droga , Oxicodona , Córtex Pré-Frontal , Animais , Oxicodona/farmacologia , Córtex Pré-Frontal/efeitos dos fármacos , Córtex Pré-Frontal/metabolismo , Masculino , Ratos , Fissura/efeitos dos fármacos , Fissura/fisiologia , Comportamento de Procura de Droga/efeitos dos fármacos , Corpo Estriado/metabolismo , Corpo Estriado/efeitos dos fármacos , Transtornos Relacionados ao Uso de Opioides/fisiopatologia , Receptores de Dopamina D1/metabolismo , Vias Neurais/efeitos dos fármacos , Ratos Sprague-Dawley , Analgésicos Opioides/farmacologiaRESUMO
BACKGROUND: According to the Chinese Society of Anesthesiology, it is recommended that patients with difficult airways be documented and notified, which will provide healthcare professionals with a direct reference when managing airways. However, compliance with this initiative remains unclear. This study was conducted to investigate the current status and need for difficult airway notification at Plastic Surgery Hospital and to explore the factors contributing to noncompliance. METHODS: Anesthesiologists, surgeons, and patients in Plastic Surgery Hospital were administered separate questionnaires regarding notification of difficult airway management. Participants were surveyed regarding their attitudes and current practices regarding difficult airway notification. In addition, questions were asked regarding the barriers that contribute to noncompliance. RESULTS: A total of 632 valid responses were obtained and analyzed, giving a response rate of 99.21%. 399 patients (89.46%) felt it was very important for anesthesiologists to inform them about their difficult airway, and 91.03% felt it was very important for them to receive a letter of their airway assessment. However, twenty-two anesthesiologists (64.7%) reported verbally informing less than 50% of patients about their difficult airway after surgery, and only four anesthesiologists informed all patients they encountered. Most surgeons (91.22%) and anesthesiologists (91.18%) believe that it is vital to inform patients verbally, while 114 surgeons (77.03%) and 31 anesthesiologists (91.18%) believe that it is essential to complete a difficult airway notification alert. Among the factors causing noncompliance, 17 (34.69%) believed that absence of mandatory rules, 9 (18.37%) believed that increased workload, and 8 (16.33%) believed that notification methods were lacking. CONCLUSIONS: The compliance to difficult airway notification remains low in Plastic Surgery Hospital despite the high incidence of difficult airways. Although anesthesiologists, surgeons, and patients are strongly in favor of it. Among the barriers to compliance were the absence of a well-developed notification system and a means of notification such as an alert form for difficult airways. This may spur the anesthesiology society to publish the notification system.
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Manuseio das Vias Aéreas , Anestesiologistas , Humanos , Manuseio das Vias Aéreas/métodos , China , Masculino , Feminino , Inquéritos e Questionários , Adulto , Pessoa de Meia-Idade , Atitude do Pessoal de Saúde , Comunicação , Documentação , Cirurgiões , Anestesiologia/métodosRESUMO
BACKGROUND: Progressive encephalomyelitis with rigidity and myoclonus (PERM) is a rare and life-threatening autoimmune disease of the central nervous system. So far, only ten cases of PERM have been reported in children worldwide, including the one in this study. CASE PRESENTATION: We report a case of an 11-year-old boy with PERM with an initial presentation of abdominal pain, skin itching, dysuria, urinary retention, truncal and limb rigidity, spasms of the trunk and limbs during sleep, deep and peripheral sensory disturbances, and dysphagia. A tissue-based assay using peripheral blood was positive, demonstrated by fluorescent staining of mouse cerebellar sections. He showed gradual and persistent clinical improvement after immunotherapy with intravenous immunoglobulin, steroids, plasmapheresis and rituximab. CONCLUSIONS: We summarized the diagnosis and treatment of a patient with PERM and performed a literature review of pediatric PERM to raise awareness among pediatric neurologists. A better comprehension of this disease is required to improve its early diagnosis, treatment, and prognosis.
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Encefalomielite , Rigidez Muscular , Mioclonia , Humanos , Masculino , Criança , Rigidez Muscular/etiologia , Encefalomielite/diagnóstico , Encefalomielite/complicações , Mioclonia/etiologia , Mioclonia/diagnósticoRESUMO
The effect of fine particulate matter (PM2.5) on the development of uveitis remains unclear. Therefore, this study was designed to investigate the role of PM2.5 in experimental autoimmune uveitis (EAU) and its potential mechanism. Our results showed that PM2.5 could exacerbate the activity of EAU, as evidenced by severer clinical and pathological changes, correlated with elevated Th17 cells frequency and IL-17A expression. Proteomic analysis revealed ferroptosis was the most significant pathway. In vivo, the levels of Fe2+, ROS, lipid ROS, and malondialdehyde, as well as the expression of TFRC, HMOX1, FTH1, and FTL1 in CD4+ T cells were increased, while GSH/GSSG ratio and the expression of ACSL1 and GPX4 were decreased after PM2.5 exposure. In vitro, the expression of TFRC and HMOX1 were increased, while the expression FTH1, FTL1, ACSL1, and GPX4 were decreased after PM2.5 exposure. Ferrostatin-1 effectively alleviated PM2.5-induced intraocular inflammation and suppressed the frequency of Th17 cells. These results suggest that PM2.5 could aggravate intraocular inflammation and immune response in EAU mice through ferroptosis. Ferroptosis could be a potential marker for the prevention and treatment of uveitis.
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Ferroptose , Material Particulado , Células Th17 , Uveíte , Ferroptose/efeitos dos fármacos , Animais , Células Th17/efeitos dos fármacos , Células Th17/imunologia , Uveíte/induzido quimicamente , Uveíte/imunologia , Material Particulado/toxicidade , Camundongos , Doenças Autoimunes/induzido quimicamente , Camundongos Endogâmicos C57BL , Modelos Animais de Doenças , FemininoRESUMO
This paper developed a method for preparing ultrasound-responsive microgels based on reversible addition fragmentation chain transfer-hetero Diels-Alder (RAFT-HAD) dynamic covalent bonding. First, a styrene cross-linked network was successfully prepared by a Diels-Alder (DA) reaction between phosphoryl dithioester and furan using double-ended diethoxyphosphoryl dithiocarbonate (BDEPDF) for RAFT reagent-mediated styrene (St) polymerization, with a double-ended dienophile linker and copolymer of furfuryl methacrylate (FMA) and St as the dienophile. Subsequently, the microgel system was constructed by the HDA reaction between phosphoryl disulfide and furan groups using the copolymer of polyethylene glycol monomethyl ether acrylate (OEGMA) and FMA as the dienophore building block and hydrophilic segment and the polystyrene pro-dienophile linker as the cross-linker and hydrophobic segment. The number of furans in the dienophile chain and the length of the dienophile linker were regulated by RAFT polymerization to investigate the effects of the single-molecule chain functional group degree, furan/dithioester ratio, and hydrophobic cross-linker length on the microgel system. The prepared microgels can achieve the reversible transformation of materials under force responsiveness, and their preparation steps are simple and adaptive to various potential applications in biomedical materials and adaptive electrical materials.
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PURPOSE: Intertrochanteric fractures undergoing proximal femoral nail antirotation (PFNA) surgery are associated with significant hidden blood loss. This study aimed to explore whether intramedullary administration of tranexamic acid (TXA) can reduce bleeding in PFNA surgery for intertrochanteric fractures in elderly individuals. METHODS: A randomized controlled trial was conducted from January 2019 to December 2022. Patients aged over 60 years with intertrochanteric fractures who underwent intramedullary fixation surgery with PFNA were eligible for inclusion and grouped according to random numbers. A total of 249 patients were initially enrolled, of which 83 were randomly allocated to the TXA group and 82 were allocated to the saline group. The TXA group received intramedullary perfusion of TXA after the bone marrow was reamed. The primary outcomes were total peri-operative blood loss and post-operative transfusion rate. The occurrence of adverse events was also recorded. Continuous data was analyzed by unpaired t-test or Mann-Whitney U test, and categorical data was analyzed by Pearson Chi-square test. RESULTS: The total peri-operative blood loss (mL) in the TXA group was significantly lower than that in the saline group (577.23 ± 358.02 vs. 716.89 ± 420.30, p = 0.031). The post-operative transfusion rate was 30.67 % in the TXA group and 47.95 % in the saline group (p = 0.031). The extent of post-operative deep venous thrombosis and the 3-month mortality rate were similar between the 2 groups. CONCLUSION: We observed that intramedullary administration of TXA in PFNA surgery for intertrochanteric fractures in elderly individuals resulted in less peri-operative blood loss and decreased transfusion rate, without any adverse effects, and is, thus, recommended.
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This study aims to assess the quality of evidence for the treatment of diabetic retinopathy with traditional Chinese medicine based on the systematic reviews/Meta-analyses of relevant studies. CNKI, Wanfang, VIP, SinoMed, PubMed, Web of Science, EMbase, and Cochrane Library were searched for the systematic reviews/Meta-analyses of traditional Chinese medicine interventions in diabetic retinopathy published from the inception to November 2023. A Measurement Tool to Assess Systematic Reviews 2(AMSTAR2) scale was used to assess the methodological quality of the included studies. An evidence map was built to present the information on intervention measures, the number of studies included in the systematic reviews/Meta-analyses, research conclusions, and methodological quality assessment results. A total of 51 studies were included. Traditional Chinese medicine interventions accounted for a large proportion of the intervention measures, followed by Chinese patent medicines. The treatment methods mainly included tonifying deficiency, activating blood, and resolving stasis. According to the AMSTAR2 scale assessment results, the descriptions of funding information for included studies, lists of excluded articles, and preliminary research protocols were particularly lacking. The evidence map showed that 48, 2, and 1 studies concluded with beneficial effects, possible beneficial effects, and unclear effects, respectively. On the whole, traditional Chinese medicine demonstrated definite efficacy in the treatment of diabetic retinopathy, while the evidence pre-sents moderate to low quality. It is suggested that higher-quality studies remain to be carried out to provide more evidence.
Assuntos
Retinopatia Diabética , Medicamentos de Ervas Chinesas , Medicina Tradicional Chinesa , Retinopatia Diabética/tratamento farmacológico , Retinopatia Diabética/terapia , Humanos , Medicamentos de Ervas Chinesas/uso terapêuticoRESUMO
Spinal cord injury (SCI) causes severe functional deficits and neuronal damage, accompanied by intense glial activation. The voltage-gated proton channel Hv1, selectively expressed on microglia, is associated with SCI progression. However, the effect of Hv1 on the phenotypes and functions of reactive astrocytes after SCI remains unclear. Here, we combined Hv1 knockout (Hv1-/- ) mice and T10 spinal cord contusion to investigate the effects of microglial Hv1 on SCI pathophysiology and the phenotypes and functions of reactive astrocytes. After SCI, astrocytes proliferated and activated in the peri-injury area and exhibited an A1-dominant phenotype. Hv1 knockout reduced neurotoxic A1 astrocytes and shifted the dominant phenotype of reactive astrocytes from A1 to A2, enhancing synaptogenesis promotion, phagocytosis, and neurotrophy of astrocytes. Moreover, synaptic and axonal remodeling as well as motor recovery after SCI benefited from the improved astrocytic functions of Hv1 knockout. Furthermore, exogenous and endogenous reactive oxygen species (ROS) in astrocytes after SCI were reduced by Hv1 knockout. Our in vitro results showed that inhibition of ROS reduced the neurotoxic A1 phenotype in primary astrocytes via the STAT3 pathway. Similar to the effect of Hv1 knockout, the application of the ROS scavenger N-acetylcysteine reduced SCI-induced neurotoxic A1 astrocytes in vivo. Based on the in vivo and vitro results, we elucidated that microglial Hv1 knockout promotes synaptic and axonal remodeling in SCI mice by decreasing neurotoxic A1 astrocytes and increasing neuroprotective A2 astrocytes via the ROS/STAT3 pathway. Therefore, the Hv1 proton channel is a promising target for the treatment of SCI.