RESUMO
AIMS: Proliferation of vascular smooth muscle cells (VSMCs) is a hallmark of pulmonary hypertension (PH). Proliferative cells utilize purine bases from the de novo purine synthesis (DNPS) pathways for nucleotide synthesis; however, it is unclear whether DNPS plays a critical role in VSMC proliferation during development of PH. The last two steps of DNPS are catalysed by the enzyme 5-aminoimidazole-4-carboxamide ribonucleotide formyltransferase/inosine monophosphate cyclohydrolase (ATIC). This study investigated whether ATIC-driven DNPS affects the proliferation of pulmonary artery smooth muscle cells (PASMCs) and the development of PH. METHODS AND RESULTS: Metabolites of DNPS in proliferative PASMCs were measured by liquid chromatography-tandem mass spectrometry. ATIC expression was assessed in platelet-derived growth factor-treated PASMCs and in the lungs of PH rodents and patients with pulmonary arterial hypertension. Mice with global and VSMC-specific knockout of Atic were utilized to investigate the role of ATIC in both hypoxia- and lung interleukin-6/hypoxia-induced murine PH. ATIC-mediated DNPS at the mRNA, protein, and enzymatic activity levels were increased in platelet-derived growth factor-treated PASMCs or PASMCs from PH rodents and patients with pulmonary arterial hypertension. In cultured PASMCs, ATIC knockdown decreased DNPS and nucleic acid DNA/RNA synthesis, and reduced cell proliferation. Global or VSMC-specific knockout of Atic attenuated vascular remodelling and inhibited the development and progression of both hypoxia- and lung IL-6/hypoxia-induced PH in mice. CONCLUSION: Targeting ATIC-mediated DNPS compromises the availability of purine nucleotides for incorporation into DNA/RNA, reducing PASMC proliferation and pulmonary vascular remodelling and ameliorating the development and progression of PH.
Assuntos
Hipertensão Pulmonar , Hipertensão Arterial Pulmonar , Camundongos , Animais , Roedores/metabolismo , Remodelação Vascular/fisiologia , Artéria Pulmonar , Purinas/metabolismo , Células Cultivadas , Hipóxia/metabolismo , RNA Mensageiro/metabolismo , Fator de Crescimento Derivado de Plaquetas/metabolismo , Proliferação de Células , Miócitos de Músculo Liso/metabolismoRESUMO
BACKGROUND: To explore the application effect of plan, do, check and action circulation management mode in improving the compliance of sepsis bundle treatment. METHODS: 113 patients with sepsis admitted from January 1 to December 31, 2018 were selected as the control group, and the bundle treatment measures of sepsis were routinely implemented. The above treatment measures were completed within 6 h. 113 patients with sepsis admitted from January 1 to December 31, 2019 were selected as the study group. All clinical staff took the same measures as the control group, supplemented by PDCA cycle management. Objective to compare the changes of compliance of clinical staff to sepsis bundle treatment before and after the implementation of PDCA cycle management. RESULTS: Compared with the control group, the study group achieved the completion rate of sepsis bundle treatment in 1 h from 66.4 to 81.4%, the completion rate in 3 h from 77.0 to 89.4%, and the completion rate in 6 h from 82.3 to 95.6%. The difference was statistically significant (P < 0.05 for all). CONCLUSIONS: The implementation of PDCA cycle management mode can effectively improve the compliance of clinical staff to the bundle treatment of sepsis, improve the treatment efficiency of sepsis, and improve the quality of medical care.
Assuntos
Cuidados Críticos/métodos , Fidelidade a Diretrizes , Sepse/terapia , Idoso , Feminino , Humanos , Masculino , Guias de Prática Clínica como Assunto , Saponinas , EsteroidesRESUMO
In the inner ear sensory epithelia, stereociliary hair bundles atop sensory hair cells are mechanosensory apparatus with planar polarized structure and orientation. This is established during development by the concerted action of tissue-level, intercellular planar cell polarity (PCP) signaling and a hair cell-intrinsic, microtubule-mediated machinery. However, how various polarity signals are integrated during hair bundle morphogenesis is poorly understood. Here, we show that the conserved cell polarity protein Par3 is essential for planar polarization of hair cells. Par3 deletion in the inner ear disrupted cochlear outgrowth, hair bundle orientation, kinocilium positioning, and basal body planar polarity, accompanied by defects in the organization and cortical attachment of hair cell microtubules. Genetic mosaic analysis revealed that Par3 functions both cell-autonomously and cell-nonautonomously to regulate kinocilium positioning and hair bundle orientation. At the tissue level, intercellular PCP signaling regulates the asymmetric localization of Par3, which in turn maintains the asymmetric localization of the core PCP protein Vangl2. Mechanistically, Par3 interacts with and regulates the localization of Tiam1 and Trio, which are guanine nucleotide exchange factors (GEFs) for Rac, thereby stimulating Rac-Pak signaling. Finally, constitutively active Rac1 rescued the PCP defects in Par3-deficient cochleae. Thus, a Par3-GEF-Rac axis mediates both tissue-level and hair cell-intrinsic PCP signaling.
Assuntos
Moléculas de Adesão Celular/metabolismo , Polaridade Celular , Células Ciliadas Auditivas Internas/citologia , Células Ciliadas Auditivas Internas/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Animais , Proteínas de Ciclo Celular , Feminino , Fatores de Troca do Nucleotídeo Guanina/metabolismo , Masculino , Camundongos , Microtúbulos/metabolismo , Mosaicismo , Órgão Espiral/metabolismo , Fosfoproteínas/metabolismo , Ligação Proteica , Proteína Quinase C/metabolismo , Proteínas Serina-Treonina Quinases/metabolismo , Transdução de Sinais , Proteína 1 Indutora de Invasão e Metástase de Linfoma de Células T/metabolismo , Proteínas rac de Ligação ao GTP/metabolismoRESUMO
BACKGROUND: Early recognition of persistent acute kidney injury (AKI) could optimize management and prevent deterioration of kidney function. The Doppler-based renal resistive index (RI) has shown promising results for predicting persistent AKI in preliminary studies. Here, we aimed to evaluate the performance of renal RI, clinical indicators, and their combinations to predict short-term kidney prognosis in septic shock patients. METHOD: We performed a retrospective study based on data from a prospective study in a single-center general ICU between November 2017 and October 2018. Patients with septic shock were included. Clinical indicators were evaluated immediately at inclusion, and renal RI was measured within the first 12 h of ICU admission after hemodynamic stabilization. Persistent AKI was defined as AKI without recovery within 72 h. A multivariable logistic regression was used to select significant variables associated with persistent AKI. The discriminative power was evaluated by a receiver operating characteristic curve analysis. RESULT: Overall, 102 patients were included, 39 of whom had persistent AKI. Renal RI was higher in the persistent AKI patients than in those without persistent AKI: 0.70 ± 0.05 vs. 0.66 ± 0.05; p = 0.001. The performance of RI to predict persistent AKI was poor, with an area under the receiver operating characteristic curve (AUROC) of 0.699 [95% confidence interval (CI) 0.600-0.786]. A clinical prediction model combining serum creatinine at inclusion and the nonrenal SOFA score showed a better prediction ability for nonrecovery, with an AUROC of 0.877 (95% CI 0.797-0.933, p = 0.0012). The addition of renal RI to this model did not improve the predictive performance. CONCLUSION: The Doppler-based renal resistive index performed poorly in predicting persistent AKI and did not improve the clinical prediction provided by a combination of serum creatinine at inclusion and the nonrenal SOFA score in patients with septic shock.
Assuntos
Injúria Renal Aguda , Choque Séptico , Humanos , Creatinina , Estudos Prospectivos , Estudos Retrospectivos , Modelos Estatísticos , Prognóstico , Injúria Renal Aguda/diagnósticoRESUMO
The circadian rhythm plays a central role in immune function, and its disruption has been closely linked to the etiology of depression. However, the mechanisms underlying the association between depression and circadian rhythm remain unclear. We found that mice deficient of Per2, a central clock component of circadian output, were resilient to neuroinflammation-induced depressive behavior. After repeated central lipopolysaccharide (LPS) injections, MCP-1, MIP-1ß, and RANTES increased in wild type (WT) but not in Per2-deficient mice. In addition, intracerebroventricular injection of RANTES resulted in depression-like behavior, and Met-RANTES, a CCR5 antagonist, could reverse depression-like behavior induced by LPS treatments. These results indicated that the Per2 gene contributes to depression via chemokines, especially RANTES. Furthermore, BMAL1 expression decreased in LPS-treated Per2-deficient mice and BMAL1 could bind to the promoter of Rantes, indicating clock gene can act as a regulator for neuroinflammation. In conclusion, Rantes, a clock-controlled gene (CCG), is involved in clock-immunological mechanisms underlying the effects of Per2 on neuroinflammation-induced depression-like behavior.
Assuntos
Proteínas CLOCK/metabolismo , Quimiocinas/metabolismo , Depressão/metabolismo , Inflamação/imunologia , Fatores de Transcrição ARNTL/metabolismo , Animais , Ritmo Circadiano/fisiologia , Lipopolissacarídeos/metabolismo , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteínas Circadianas Period/metabolismoRESUMO
CONTEXT: Global morbidity from chronic obstructive pulmonary disease (COPD) is high worldwide. Diaphragm pacing (DP) can maintain the natural, negative pressure breathing of COPD patients with diaphragmatic muscle dysfunction. The YiqiDitanTongfu (YDTF) decoction has been used clinically with COPD patients to help them to wean from mechanical ventilation, with their ventilation functions being improved and the success rate of weaning being largely increased. OBJECTIVE: The study intended to investigate the combined therapeutic effects of external DP and the YDTF decoction for COPD patients who have had difficulty weaning from mechanical ventilation. DESIGN: This study was a retrospective cohort study. SETTING: The study occurred at the Hebei General Hospital and Hebei Province Chest Hospital (Hebei Province, Shijiazhuang, China). PARTICIPANTS: Participants were 90 patients with COPD + type 1 respiratory failure, 101 patients with COPD + Type 2 respiratory failure, and 96 patients with COPD at the compensated stage. INTERVENTION: The participants were randomly divided into 3 groups: (1) traditional treatment (control group), (2) traditional treatment plus treatment with a diaphragm pacemaker (DP group), and (3) traditional treatment plus treatment with a DP and a YDTF decoction (DP + YDTF group). All treatments occurred for 12 d. OUTCOME MEASURES: Relevant outcomes were measured and compared at baseline and postintervention, including the rapid shallow breathing index, tidal volume, maximum inspiratory pressure, degree of diaphragmatic muscle activity, maximum expiratory pressure, the successful rates of weaning from mechanical ventilation, the potential of hydrogen, the partial pressure of oxygen, partial pressure of carbon dioxide, and oxygen saturation. RESULTS: The patients treated with the DP plus the YDTF decoction were more successful in weaning from mechanical ventilation than those treated with DP. Of the patients with COPD + type 1 respiratory failure, 86.67% succeeded vs 70.00% of the DP patients. Of patients with COPD + type 2 respiratory failure, 87.88% succeeded vs 79.41% of the DP patients. CONCLUSION: The DP plus the YDTF concoction acted as a successful treatment for heart failure caused by CPOD in comparison with the DP or YDTF alone, providing evidence that the DP + YDTF concoction can serve as a competitive method for helping COPD patients to wean from mechanical ventilation.
Assuntos
Medicina Herbária , Medicina Tradicional Chinesa , Marca-Passo Artificial , Doença Pulmonar Obstrutiva Crônica/terapia , Desmame do Respirador/métodos , China , Diafragma , Humanos , Respiração Artificial , Estudos RetrospectivosRESUMO
Asymmetric cell division requires the establishment of cortical cell polarity and the orientation of the mitotic spindle along the axis of cell polarity. Evidence from invertebrates demonstrates that the Par3/Par6/aPKC and NuMA/LGN/Gαi complexes, which are thought to be physically linked by the adaptor protein mInscuteable (mInsc), play indispensable roles in this process. However, the molecular basis for the binding of LGN to NuMA and mInsc is poorly understood. The high-resolution structures of the LGN/NuMA and LGN/mInsc complexes presented here provide mechanistic insights into the distinct and highly specific interactions of the LGN TPRs with mInsc and NuMA. Structural comparisons, together with biochemical and cell biology studies, demonstrate that the interactions of NuMA and mInsc with LGN are mutually exclusive, with mInsc binding preferentially. Our results suggest that the Par3/mInsc/LGN and NuMA/LGN/Gαi complexes play sequential and partially overlapping roles in asymmetric cell division.
Assuntos
Antígenos Nucleares/química , Proteínas de Transporte/química , Proteínas de Ciclo Celular/química , Divisão Celular/fisiologia , Proteínas Associadas à Matriz Nuclear/química , Proteínas Adaptadoras de Transdução de Sinal , Animais , Antígenos Nucleares/genética , Antígenos Nucleares/fisiologia , Proteínas de Transporte/genética , Proteínas de Transporte/fisiologia , Moléculas de Adesão Celular/química , Moléculas de Adesão Celular/metabolismo , Moléculas de Adesão Celular/fisiologia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/fisiologia , Polaridade Celular , Cristalografia por Raios X , Escherichia coli/genética , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/química , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/metabolismo , Subunidade alfa Gi2 de Proteína de Ligação ao GTP/fisiologia , Humanos , Camundongos , Modelos Moleculares , Mutagênese , Proteínas Associadas à Matriz Nuclear/genética , Proteínas Associadas à Matriz Nuclear/fisiologia , Estrutura Terciária de Proteína , Transporte Proteico , Fuso Acromático/metabolismoRESUMO
Background: Drug-induced alterations in gene expression play an important role in the development of addictive behavior. Numerous transcription factors have been implicated in mediating the gene expression changes that occur in drug addiction. Nuclear factor kappa B is an inducible transcription factor complex that is rapidly activated by diverse stimuli. Methods: We performed next-generation high-throughput sequencing of the prefrontal cortex in a mouse model of repeated cocaine administration combined with pharmacological nuclear factor kappa B inhibition to identify nuclear factor kappa B target genes that participate in the cocaine addiction process. Results: We found that the nuclear factor kappa B antagonist sodium diethyldithiocarbamate trihydrate significantly reversed the cocaine-induced expression changes of the amphetamine addiction pathway. Genes that demonstrated differential expression in response to cocaine treatment that was also reversed by sodium diethyldithiocarbamate trihydrate were enriched for the axon guidance pathway. Furthermore, the nuclear factor kappa B homo-dimer motif could be mapped to 86 of these sodium diethyldithiocarbamate trihydrate-reversed genes, which were also enriched for axon guidance. Conclusions: We suggest that nuclear factor kappa B directly modifies the expression of axon guidance pathway members, leading to cocaine sensitization. Our findings reveal the role of prefrontal cortex nuclear factor kappa B activity in addiction and uncover the molecular mechanisms by which nuclear factor kappa B drives changes in the addicted brain.
Assuntos
Transtornos Relacionados ao Uso de Cocaína/genética , Cocaína/farmacologia , Inibidores da Captação de Dopamina/farmacologia , Sequenciamento do Exoma/métodos , Sequenciamento de Nucleotídeos em Larga Escala/métodos , NF-kappa B/genética , Córtex Pré-Frontal/metabolismo , Animais , Comportamento Animal , Modelos Animais de Doenças , Ditiocarb/farmacologia , Camundongos , NF-kappa B/antagonistas & inibidores , Sequestrantes/farmacologiaRESUMO
The large nuclear mitotic apparatus (NuMA) protein is an essential player in mitotic spindle assembly and maintenance. We report here the identification of Astrin, a spindle- and kinetochore-associated protein, as a novel interactor of NuMA. We show that the C-terminal tail of NuMA can directly bind to the C terminus of Astrin and that this interaction helps to recruit Astrin to microtubules. Knockdown of NuMA by RNA interference dramatically impaired Astrin recruitment to the mitotic spindle. Overexpression of the N terminus of mammalian homologue of Drosophila Pins (LGN), which blocks the microtubule binding of NuMA and competes with Astrin for NuMA binding, also led to similar results. Furthermore, we found that cytoplasmic dynein is required for the spindle pole accumulation of Astrin, and dynein-mediated transport is important for balanced distribution of Astrin between spindle poles and kinetochores. On the other hand, if Astrin levels are reduced, then NuMA could not efficiently concentrate at the spindle poles. Our findings reveal a direct physical link between two important regulators of mitotic progression and demonstrate the critical role of the NuMA-Astrin interaction for accurate cell division.
Assuntos
Antígenos Nucleares/metabolismo , Proteínas de Ciclo Celular/metabolismo , Mitose/fisiologia , Proteínas Associadas à Matriz Nuclear/metabolismo , Fuso Acromático/metabolismo , Animais , Antígenos Nucleares/genética , Células COS , Proteínas de Ciclo Celular/genética , Chlorocebus aethiops , Drosophila melanogaster , Dineínas/genética , Dineínas/metabolismo , Técnicas de Silenciamento de Genes , Células HeLa , Humanos , Proteínas Associadas à Matriz Nuclear/genética , Domínios Proteicos , Homologia de Sequência de Aminoácidos , Fuso Acromático/genéticaRESUMO
The Crumbs (Crb) complex, formed by Crb, PALS1, and PATJ, is evolutionarily conserved in metazoans and acts as a master cell-growth and -polarity regulator at the apical membranes in polarized epithelia. Crb intracellular functions, including its direct binding to PALS1, are mediated by Crb's highly conserved 37-residue cytoplasmic tail. However, the mechanistic basis governing the highly specific Crb-PALS1 complex formation is unclear, as reported interaction between the Crb tail (Crb-CT) and PALS1 PSD-95/DLG/ZO-1 (PDZ) domain is weak and promiscuous. Here we have discovered that the PDZ-Src homolgy 3 (SH3)-Guanylate kinase (GK) tandem of PALS1 binds to Crb-CT with a dissociation constant of 70 nM, which is â¼ 100-fold stronger than the PALS1 PDZ-Crb-CT interaction. The crystal structure of the PALS1 PDZ-SH3-GK-Crb-CT complex reveals that PDZ-SH3-GK forms a structural supramodule with all three domains contributing to the tight binding to Crb. Mutations disrupting the tertiary interactions of the PDZ-SH3-GK supramodule weaken the PALS1-Crb interaction and compromise PALS1-mediated polarity establishment in Madin-Darby canine kidney (MDCK) cysts. We further show that specific target binding of other members of membrane-associated guanylate kinases (MAGUKs) (e.g., CASK binding to neurexin) also requires the presence of their PDZ-SH3-GK tandems.
Assuntos
Polaridade Celular , Proteínas de Membrana/química , Sequência de Aminoácidos , Animais , Cristalografia por Raios X , Citoplasma/metabolismo , Cães , Células Epiteliais/metabolismo , Escherichia coli/metabolismo , Guanilato Quinases/química , Células Madin Darby de Rim Canino , Modelos Moleculares , Dados de Sequência Molecular , Mutação , Domínios PDZ , Ligação Proteica , Multimerização Proteica , Estrutura Terciária de Proteína , Homologia de Sequência de Aminoácidos , Domínios de Homologia de srcRESUMO
We summarized proposals submitted and funded in the discipline of microbiology of the Department of Life Sciences of National Natural Science Foundation of China in 2016. The traits and concerns in different sub-disciplines as well as distinctive funding programs were addressed, and the prior funding fields were prospected. The information may provide references for researchers who apply funding at the discipline of microbiology.
Assuntos
Microbiologia/economia , Disciplinas das Ciências Naturais/economia , China , Fundações/economia , Microbiologia/organização & administração , Disciplinas das Ciências Naturais/organização & administração , Projetos de PesquisaRESUMO
The development and maintenance of polarized epithelial tissue requires a tightly controlled orientation of mitotic cell division relative to the apical polarity axis. Hepatocytes display a unique polarized architecture. We demonstrate that mitotic hepatocytes asymmetrically segregate their apical plasma membrane domain to the nascent daughter cells. The non-polarized nascent daughter cell can form a de novo apical domain with its new neighbor. This asymmetric segregation of apical domains is facilitated by a geometrically distinct "apicolateral" subdomain of the lateral surface present in hepatocytes. The polarity protein partitioning-defective 1/microtubule-affinity regulating kinase 2 (Par1b/MARK2) translates this positional landmark to cortical polarity by promoting the apicolateral accumulation of Leu-Gly-Asn repeat-enriched protein (LGN) and the capture of nuclear mitotic apparatus protein (NuMA)-positive astral microtubules to orientate the mitotic spindle. Proliferating hepatocytes thus display an asymmetric inheritance of their apical domains via a mechanism that involves Par1b and LGN, which we postulate serves the unique tissue architecture of the developing liver parenchyma.
Assuntos
Membrana Celular/fisiologia , Polaridade Celular/fisiologia , Hepatócitos/fisiologia , Peptídeos e Proteínas de Sinalização Intracelular/fisiologia , Metaloproteases/fisiologia , Proteínas Mitocondriais/fisiologia , Fuso Acromático/fisiologia , Proliferação de Células , Células Hep G2/fisiologia , HumanosRESUMO
Based on a wrap-up of the research proposals received and awards made during 2011 through 2015 in the discipline of microbiology of the Department of Life Sciences, National Natural Science Foundation of China, this article presents a statistic analysis of award recipient institutions and main research trends, and attempts a prospective prioritization of the funding areas from the points of encouraging interdisciplinary research, optimizing funding instruments and strengthening talent training, with a view to providing reference for scientists and researchers in the field of microbiology.
Assuntos
Organização do Financiamento/organização & administração , Microbiologia/economia , Projetos de Pesquisa , China , Organização do Financiamento/estatística & dados numéricos , Organização do Financiamento/tendências , Humanos , Microbiologia/organização & administração , Microbiologia/tendências , Projetos de Pesquisa/estatística & dados numéricos , Projetos de Pesquisa/tendências , Recursos HumanosRESUMO
Myosin X (Myo X), also known as MYO10, is an unconventional actin-based motor protein that plays an important role in filopodium formation. Its intra-filopodia movement, an event tightly associated with the function of Myo X, has been extensively studied. However, how the motor activity of Myo X and the direction of its movements are regulated remains largely unknown. In our previous study, we demonstrated that DCC (for 'deleted in colorectal carcinoma') and neogenin (neogenin 1, NEO1 or NGN), a family of immunoglobin-domain-containing transmembrane receptors for netrins, interact with Myo X and that DCC is a cargo of Myo X to be delivered to the neurites of cultured neurons. Here, we provide evidence for DCC and neogenin as regulators of Myo X. DCC promotes movement of Myo X along basal actin filaments and enhances Myo-X-mediated basal filopodium elongation. By contrast, neogenin appears to suppress Myo X movement on the basal side, but increases its movement towards the apical and dorsal side of a cell, promoting dorsal filopodium formation and growth. Further studies have demonstrated that DCC, but not neogenin, enhances integrin-mediated tyrosine phosphorylation of focal adhesion kinase and basal F-actin reorganization, providing a cellular mechanism underlying their distinct effects on Myo X. These results thus demonstrate differential regulatory roles on Myo X activity by its cargo proteins, DCC and neogenin, revealing different cellular functions of DCC and neogenin.
Assuntos
Proteínas de Membrana/metabolismo , Miosinas/metabolismo , Receptores de Superfície Celular/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Actinas/metabolismo , Animais , Compartimento Celular , Linhagem Celular , Movimento Celular/fisiologia , Receptor DCC , Proteínas de Fluorescência Verde/genética , Proteínas de Fluorescência Verde/metabolismo , Proteínas de Membrana/genética , Camundongos , Modelos Biológicos , Miosinas/genética , Neurônios/fisiologia , Transporte Proteico , Pseudópodes/fisiologia , Receptores de Superfície Celular/genética , Proteínas Recombinantes de Fusão/genética , Proteínas Recombinantes de Fusão/metabolismo , Proteínas Supressoras de Tumor/genéticaRESUMO
Plant viruses are excellent tools for studying microbial-plant interactions as well as the complexities of host activities. Our study focuses on the role of C2 encoded by Beet severe curly top virus (BSCTV) in the virus-plant interaction. Using BSCTV C2 as bait in a yeast two-hybrid screen, a C2-interacting protein, S-adenosyl-methionine decarboxylase 1 (SAMDC1), was identified from an Arabidopsis thaliana cDNA library. The interaction was confirmed by an in vitro pull-down assay and a firefly luciferase complemention imaging assay in planta. Biochemical analysis further showed that the degradation of the SAMDC1 protein was inhibited by MG132, a 26S proteasome inhibitor, and that C2 could attenuate the degradation of the SAMDC1 protein. Genetic analysis showed that loss of function of SAMDC1 resulted in reduced susceptibility to BSCTV infection and reduced viral DNA accumulation, similar to the effect of BSCTV C2 deficiency. Bisulfite sequencing analysis further showed that C2 deficiency caused enhanced DNA methylation of the viral genome in infected plants. We also showed that C2 can suppress de novo methylation in the FWA transgenic assay in the C2 transgene background. Overexpression of SAMDC1 can mimic the suppressive activity of C2 against green fluorescent protein-directed silencing. These results suggest that C2 interferes with the host defense mechanism of DNA methylation-mediated gene silencing by attenuating the 26S proteasome-mediated degradation of SAMDC1.
Assuntos
Adenosilmetionina Descarboxilase/química , Arabidopsis/virologia , Metilação de DNA , Proteínas de Ligação a DNA/metabolismo , Geminiviridae/genética , Inativação Gênica , Proteínas Virais/metabolismo , Arabidopsis/enzimologia , Proteínas de Ligação a DNA/genética , Geminiviridae/metabolismo , Genoma Viral , Plantas Geneticamente Modificadas/enzimologia , Plantas Geneticamente Modificadas/virologia , Técnicas do Sistema de Duplo-Híbrido , Proteínas Virais/genéticaRESUMO
Netrins regulate axon path-finding during development, but the underlying mechanisms are not well understood. Here, we provide evidence for the involvement of the unconventional myosin X (Myo X) in netrin-1 function. We find that Myo X interacts with the netrin receptor deleted in colorectal cancer (DCC) and neogenin, a DCC-related protein. Expression of Myo X redistributes DCC to the cell periphery or to the tips of neurites, whereas its silencing prevents DCC distribution in neurites. Moreover, expression of DCC, but not neogenin, stimulates Myo X-mediated formation and elongation of filopodia, suggesting that Myo X function may be differentially regulated by DCC and neogenin. The involvement of Myo X in netrin-1 function was further supported by the effects of inhibiting Myo X function in neurons. Cortical explants derived from mouse embryos expressing a motor-less Myo X exhibit reduced neurite outgrowth in response to netrin-1 and chick commissural neurons expressing the motor-less Myo X, or in which Myo X is silenced using microRNA (miRNA), show impaired axon projection in vivo. Taken together, these results identify a novel role for Myo X in regulating netrin-1 function.
Assuntos
Axônios/fisiologia , Miosinas/metabolismo , Fatores de Crescimento Neural/metabolismo , Receptores de Superfície Celular/metabolismo , Proteínas Supressoras de Tumor/metabolismo , Animais , Células COS , Linhagem Celular , Embrião de Galinha , Chlorocebus aethiops , Humanos , Proteínas de Membrana/metabolismo , Camundongos , MicroRNAs/farmacologia , Dados de Sequência Molecular , Miosinas/efeitos dos fármacos , Fatores de Crescimento Neural/farmacologia , Receptores de Netrina , Netrina-1 , Ratos , Proteínas Supressoras de Tumor/farmacologiaRESUMO
BACKGROUND: Acute lung injury (ALI) is a serious disease with high incidence in ICU, and impaired mitochondria function plays a significant role in ALI. In this study, we examined the possible roles of exogenous hydrogen sulfide (H2S) in lung mitochondria regulation in ALI rats. METHODS: The rat ALI model was induced by an intra-tongue vein Lipopolysaccharide (LPS) injection. We used sodium hydrosulphide (NaHS) as the H2S donor. We randomly divided 40 Sprague-Dawley rats into five groups: control, LPS injury, LPS + low-dose NaHS (0.78 mg ⢠kg(-1)), LPS + middle-dose NaHS (1.56 mg ⢠kg(-1)), and LPS + high-dose NaHS (3.12 mg ⢠kg(-1)). Rats were killed 3 h after NaHS administration. We calculated a semi-quantitative histological index of lung injury assessments and measured the lung wet-to-dry weight ratio. We further analyzed serum for interleukin-1ß levels using enzyme-linked immunosorbent assays. We observed lung mitochondria ultrastructures with an electron microscope. We examined oxidative stress markers in lung mitochondria and the mitochondrial swelling and activity. We analyzed lung mitochondria and cytosol Cyt-c protein expression using Western blotting. RESULTS: Compared to the control group, the quantitative assessment score index, wet-to-dry weight ratios, and interleukin-1ß content in the LPS injury group were significantly increased and the mitochondrial ultrastructure damaged. Furthermore, mitochondrial activity, adenosine triphosphatease, superoxide dismutase, glutathione peroxidase, and mitochondrial Cyt-c protein expression were significantly decreased, and malondialdehyde content, mitochondrial swelling, and cytosol Cyt-c protein expression were significantly increased in the LPS injury group compared to the control group. These effects were lessened by NaHS. CONCLUSION: Exogenous H2S provided a protective effect against ALI by decreasing the mitochondrial lipid peroxidation level and protecting the cell structure in the LPS-induced rat models. Its regulatory effect on lung mitochondria is positively correlated with the dosage.
Assuntos
Lesão Pulmonar Aguda/tratamento farmacológico , Interleucina-1beta/sangue , Mitocôndrias/efeitos dos fármacos , Sulfetos/farmacologia , Lesão Pulmonar Aguda/fisiopatologia , Animais , Citocromos c/metabolismo , Citosol/metabolismo , Modelos Animais de Doenças , Relação Dose-Resposta a Droga , Ensaio de Imunoadsorção Enzimática , Peroxidação de Lipídeos/efeitos dos fármacos , Lipopolissacarídeos/toxicidade , Pulmão/efeitos dos fármacos , Pulmão/fisiopatologia , Masculino , Malondialdeído/metabolismo , Mitocôndrias/metabolismo , Ratos , Ratos Sprague-Dawley , Sulfetos/administração & dosagem , Superóxido Dismutase/metabolismoRESUMO
OBJECTIVE: To evaluate the clinical practice of intensive care unit (ICU) physicians at Hebei General Hospital in identifying patients meeting the diagnostic criteria for acute respiratory distress syndrome (ARDS) and the current status of invasive mechanical ventilation management and adjunctive therapy in these patients, and to analyze the incidence and clinical outcomes of ARDS. METHODS: A retrospective cohort study was conducted. The patients who were hospitalized in the ICU of Hebei General Hospital from April 10, 2017 to June 30, 2022 and met the Berlin definition diagnostic criteria for ARDS were enrolled as study subjects. Artificial intelligence (AI) technology was applied to search the basic information (age, gender, height, body weight, etc.), auxiliary examination, electronic medical record, non-drug doctor's advice, drug doctor's advice, critical report, scoring system, monitoring master table and other data of the above medical records in the electronic medical record system of the hospital. The first set of laboratory indicators sequentially retrieved from the system daily from 05:00 to 10:00 and vital signs and mechanical ventilation-related parameters recorded in the "critical care report" at 06:00 daily were extracted, and outcome indicators of the patients were collected. RESULTS: After screening and analysis, a total of 255 patients who met the ARDS diagnostic criteria were finally enrolled. The overall incidence of ARDS in the ICU accounted for 3.4% (255/7 434) of the total number of ICU patients, of which mild, moderate and severe ARDS accounted for 22.4% (57/255), 49.0% (125/255), and 28.6% (73/255), respectively, while the recognition rates of clinical doctors were 71.9% (41/57), 58.4% (73/125) and 71.2% (52/73), respectively. During the ICU stay, 250 patients (98.0%) received only invasive mechanical ventilation, while 5 patients (2.0%) received both non-invasive and invasive mechanical ventilation. The tidal volume/ideal body weight of ARDS patients was 7.64 (6.49, 9.01) mL/kg, and the positive end-expiratory pressure (PEEP) was 8.0 (5.0, 10.0) cmH2O (1 cmH2O ≈ 0.098 kPa). In addition, during the diagnosis and detection of ARDS, only 7 patients were recorded the platform pressure and 6 patients were recorded the drive pressure. Regarding adjunctive therapies, 137 patients (53.7%) received deep sedation, 26 patients (10.2%) underwent lung recruitment, 55 patients (21.6%) received prone ventilation, 42 patients (16.5%) were treated with high-dose steroids, 19 patients (7.5%) were treated with neuromuscular blockade, and 8 patients (3.1%) were treated with extracorporeal membrane oxygenation (ECMO). Finally, 70 patients (27.5%) were discharged automatically, while 50 patients (19.6%) died in the ICU, of which the ICU mortality of mild, moderate, and severe ARDS patients were 15.8% (9/57), 22.4% (28/125), and 17.8% (13/73), respectively. After follow-up, it was found that all 70 patients discharged automatically died within 28 days after discharge, and the overall ICU mortality adjusted accordingly was 47.1% (120/255). CONCLUSIONS: The overall incidence of ARDS in ICU patients at Hebei General Hospital is relatively low, with a high recognition rate by clinical physicians. Despite the high level of compliance and implementation of lung protective ventilation strategies and auxiliary treatment measures, it is still necessary to further improve the level of standardization in the implementation of small tidal volume and respiratory mechanics monitoring. For the implementation of auxiliary measures such as prone ventilation, it is necessary to further improve the enthusiasm of medical staff. The mortality in ICU is relatively low in ARDS patients, while the rate of spontaneous discharge is relatively high.
Assuntos
Inteligência Artificial , Unidades de Terapia Intensiva , Respiração Artificial , Síndrome do Desconforto Respiratório , Humanos , Síndrome do Desconforto Respiratório/terapia , Síndrome do Desconforto Respiratório/diagnóstico , Síndrome do Desconforto Respiratório/epidemiologia , Estudos Retrospectivos , Respiração Artificial/métodos , Masculino , Feminino , Pessoa de Meia-IdadeRESUMO
"Boundarics in Biomedicine" is a cutting-edge interdisciplinary discipline, which is of great significance for understanding the origin of life, the interaction between internal and external environments, and the mechanism of disease occurrence and evolution. Here, the definition of Boundarics in Biomedicine is first described, including its connotation, research object, research method, challenges, and future perspectives. "Boundarics in Biomedicine" is a cutting-edge interdisciplinary discipline involving multiple fields (e.g., bioscience, medicine, chemistry, materials science, and information science) dedicated to investigating and solving key scientific questions in the formation, identification, and evolution of living organism boundaries. Specifically, it encompasses 3 levels: (a) the boundary between the living organism and the external environment, (b) internal boundary within living organism, and (c) the boundary related to disease in living organism. The advancement of research in Boundarics in Biomedicine is of great scientific significance for understanding the origin of life, the interaction between internal and external environments, and the mechanism of disease occurrence and evolution, thus providing novel principles, technologies, and methods for early diagnosis and prevention of major diseases, personalized drug development, and prognosis assessment (Fig. 1).
RESUMO
Objective: We conducted a systematic review to assess the advantages and disadvantages of levosimendan in patients with sepsis compared with placebo, milrinone, and dobutamine and to explore the clinical efficacy of different concentrations of levosimendan. Methods: PubMed, Web of Science, Cochrane Library, Embase, CNKI, Wanfang data, VIP, and CBM databases were searched using such keywords as simendan, levosimendan, and sepsis. The search time was from the establishment of the database to July 2023. Two researchers were responsible for literature screening and data collection respectively. After the risk of bias in the included studies was evaluated, network meta-analysis was performed using R software gemtc and rjags package. Results: Thirty-two randomized controlled trials (RCTs) were included in the network meta-analysis. Meta-analysis results showed that while levosimendan significantly improved CI levels at either 0.1 µg/kg/min (mean difference [MD] [95%CrI] = 0.41 [-0.43, 1.4]) or 0.2 µg/kg/min (MD [95%CrI] =0.54 [0.12, 0.99]). Levosimendan, at either 0.075 µg/kg/min (MD [95% CrI] =0.033 [-0.75, 0.82]) or 0.2 µg/kg/min (MD [95% CrI] = -0.014 [-0.26, 0.23]), had no significant advantage in improving Lac levels. Levosimendan, at either 0.1 µg/kg/min (RR [95% CrI] = 0.99 [0.73, 1.3]) or 0.2 µg/kg/min (RR [95% CrI] = 1.0 [0.88, 1.2]), did not have a significant advantage in reducing mortality. Conclusion: The existing evidence suggests that levosimendan can significantly improve CI and lactate levels in patients with sepsis, and levosimendan at 0.1 µg/kg/min might be the optimal dose. Unfortunately, all interventions in this study failed to reduce the 28-day mortality. Systematic Review Registration: https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42023441220.