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1.
Cell ; 175(6): 1591-1606.e19, 2018 11 29.
Artigo em Inglês | MEDLINE | ID: mdl-30500538

RESUMO

The mammalian liver possesses a remarkable regenerative ability. Two modes of damage response have been described: (1) The "oval cell" response emanates from the biliary tree when all hepatocytes are affected by chronic liver disease. (2) A massive, proliferative response of mature hepatocytes occurs upon acute liver damage such as partial hepatectomy (PHx). While the oval cell response has been captured in vitro by growing organoids from cholangiocytes, the hepatocyte proliferative response has not been recapitulated in culture. Here, we describe the establishment of a long-term 3D organoid culture system for mouse and human primary hepatocytes. Organoids can be established from single hepatocytes and grown for multiple months, while retaining key morphological, functional and gene expression features. Transcriptional profiles of the organoids resemble those of proliferating hepatocytes after PHx. Human hepatocyte organoids proliferate extensively after engraftment into mice and thus recapitulate the proliferative damage-response of hepatocytes.


Assuntos
Proliferação de Células , Hepatócitos/metabolismo , Organoides/metabolismo , Animais , Técnicas de Cultura de Células , Células Cultivadas , Hepatócitos/citologia , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Organoides/citologia , Células-Tronco/citologia , Células-Tronco/metabolismo , Fatores de Tempo
2.
Circ Res ; 135(7): 708-721, 2024 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-39176657

RESUMO

BACKGROUND: Despite endothelial dysfunction being an initial step in the development of hypertension and associated cardiovascular/renal injuries, effective therapeutic strategies to prevent endothelial dysfunction are still lacking. GPR183 (G protein-coupled receptor 183), a recently identified G protein-coupled receptor for oxysterols and hydroxylated metabolites of cholesterol, has pleiotropic roles in lipid metabolism and immune responses. However, the role of GPR183 in the regulation of endothelial function remains unknown. METHODS: Endothelial-specific GPR183 knockout mice were generated and used to examine the role of GPR183 in endothelial senescence by establishing 2 independent hypertension models: desoxycorticosterone acetate/salt-induced and Ang II (angiotensin II)-induced hypertensive mice. Echocardiography, transmission electron microscopy, blood pressure measurement, vasorelaxation response experiments, flow cytometry analysis, and chromatin immunoprecipitation analysis were performed in this study. RESULTS: Endothelial GPR183 was significantly induced in hypertensive mice, which was further confirmed in renal biopsies from subjects with hypertensive nephropathy. Endothelial-specific deficiency of GPR183 markedly alleviated cardiovascular and renal injuries in hypertensive mice. Moreover, we found that GPR183 regulated endothelial senescence in both hypertensive mice and aged mice. Mechanistically, GPR183 disrupted circadian signaling by inhibiting PER1 (period circadian regulator 1) expression, thereby facilitating endothelial senescence and dysfunction through the cAMP (cyclic adenosine monophosphate)/PKA (protein kinase A)/CREB (cAMP-response element binding protein) signaling pathway. Importantly, pharmacological inhibition of the oxysterol-GPR183 axis by NIBR189 or clotrimazole ameliorated endothelial senescence and cardiovascular/renal injuries in hypertensive mice. CONCLUSIONS: This study discovers a previously unrecognized role of GPR183 in promoting endothelial senescence. Pharmacological targeting of GPR183 may be an innovative therapeutic strategy for hypertension and its associated complications.


Assuntos
Senescência Celular , Hipertensão , Oxisteróis , Receptores Acoplados a Proteínas G , Animais , Humanos , Masculino , Camundongos , Células Cultivadas , Proteína de Ligação ao Elemento de Resposta ao AMP Cíclico/metabolismo , Acetato de Desoxicorticosterona , Células Endoteliais/metabolismo , Hipertensão/metabolismo , Hipertensão/fisiopatologia , Camundongos Endogâmicos C57BL , Camundongos Knockout , Oxisteróis/metabolismo , Receptores Acoplados a Proteínas G/metabolismo , Receptores Acoplados a Proteínas G/genética , Transdução de Sinais
3.
Eur J Clin Microbiol Infect Dis ; 43(8): 1517-1531, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38842766

RESUMO

BACKGROUND: Group A streptococcal(GAS) meningitis is a severe disease with a high case fatality rate. In the era of increasing GAS meningitis, our understanding about this disease is limited. PURPOSE: To gain a better understanding about GAS meningitis. METHODS: Five new cases with GAS meningitis were reported. GAS meningitis related literatures were searched for systematic review in PUBMED and EMBASE. Case reports and case series on paediatric cases were included. Information on demographics, risk factors, symptoms, treatments, outcomes, and emm types of GAS was summarized. RESULTS: Totally 263 cases were included. Among 100 individuals, 9.9% (8/81) had prior varicella, 11.1% (9/81) had anatomical factors, and 53.2% (42/79) had extracranial infections. Soft tissue infections were common among infants (10/29, 34.5%), while ear/sinus infections were more prevalent in children ≥ 3 years (21/42, 50.0%). The overall case fatality rate (CFR) was 16.2% (12/74). High risk of death was found in patients with shock or systemic complications, young children(< 3 years) and cases related to hematogenic spread. The predominate cause of death was shock(6/8). Among the 163 patients included in case series studies, ear/sinus infections ranged from 21.4 to 62.5%, while STSS/shock ranged from 12.5 to 35.7%, and the CFR ranged from 5.9 to 42.9%. CONCLUSIONS: A history of varicella, soft tissue infections, parameningeal infections and CSF leaks are important clinical clues to GAS in children with meningitis. Young children and hematogenic spread related cases need to be closely monitored for shock due to the high risk of death.


Assuntos
Meningites Bacterianas , Infecções Estreptocócicas , Streptococcus pyogenes , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Antibacterianos/uso terapêutico , Meningites Bacterianas/tratamento farmacológico , Meningites Bacterianas/microbiologia , Meningites Bacterianas/mortalidade , Fatores de Risco , Infecções Estreptocócicas/tratamento farmacológico , Infecções Estreptocócicas/microbiologia , Infecções Estreptocócicas/mortalidade
4.
BMC Infect Dis ; 24(1): 745, 2024 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-39075343

RESUMO

BACKGROUND: Data on pyogenic liver abscess (PLA) of children in China have been limited. We aimed to summarize the clinical feather, microbiological characteristics, management, and outcome of PLA in children. METHOD: We retrospectively reviewed PLA cases from January 2008 to June 2023 at Beijing Children's Hospital. Clinical characteristics, pathogens and management were analyzed. RESULTS: We diagnosed 57 PLA patients in our center. The median onset age was 4.5 years and the male-to-female ratio was 1.6:1. The median diagnostic time was nine days and the median length of stay was 22 days. Twenty-eight patients (49.1%) had predisposing factors, around 71.4% of the patients had malignant hematology and primary immunodeficiency disease. Patients with underlying factors were more likely to have extrahepatic organ involvement (p = 0.024), anemia (p < 0.001), single abscess (p = 0.042), unilateral involvement (p = 0.039), and small size of the abscess (p = 0.008). Twenty-four patients (42.1%) had extrahepatic organ involvement. Pathogens were identified in 17 patients (29.8%), the most common pathogens were Klebsiella pneumoniae and Staphylococcus aureus. The positive rate of metagenomic next-generation sequencing (mNGS) was 87.5% (7/8). On multivariable analysis, the extrahepatic organ involved (p = 0.029) and hepatomegaly (p = 0.025) were two independent factors associated with poor outcomes. CONCLUSIONS: PLA is usually seen in children with predisposing factors. Malignant hematology and primary immunodeficiency disease were the most common underlying diseases. Extrahepatic organ involvement and hepatomegaly are associated with poor prognosis. Increased use of mNGS could be beneficial for identifying pathogens.


Assuntos
Abscesso Hepático Piogênico , Humanos , Abscesso Hepático Piogênico/microbiologia , Abscesso Hepático Piogênico/epidemiologia , Masculino , Feminino , Estudos Retrospectivos , Pré-Escolar , Criança , Lactente , Pequim/epidemiologia , Adolescente , Klebsiella pneumoniae/isolamento & purificação , Antibacterianos/uso terapêutico , Fatores de Risco , Staphylococcus aureus/isolamento & purificação
5.
Mol Ther ; 31(10): 3034-3051, 2023 10 04.
Artigo em Inglês | MEDLINE | ID: mdl-37452495

RESUMO

Oxidative stress plays a central role in the pathophysiology of acute kidney injury (AKI). Although RNA is one of the most vulnerable cell components to oxidative damage, it is unclear whether RNA oxidation is involved in the pathogenesis of AKI. In this study, we found that the level of RNA oxidation was significantly enhanced in kidneys of patients with acute tubular necrosis (ATN) and in the renal tubular epithelial cells (TECs) of mice with AKI, and oxidized RNA overload resulted in TEC injury. We further identified interferon-stimulated gene 20 (ISG20) as a novel regulator of RNA oxidation in AKI. Tubule-specific deficiency of ISG20 significantly aggravated renal injury and RNA oxidation in the ischemia/reperfusion-induced AKI mouse model and ISG20 restricted RNA oxidation in an exoribonuclease activity-dependent manner. Importantly, overexpression of ISG20 protected against oxidized RNA overproduction and renal ischemia/reperfusion injury in mice and ameliorated subsequent protein aggresome accumulation, endoplasmic reticulum stress, and unfolded protein response. Thus, our findings provide direct evidence that RNA oxidation contributes to the pathogenesis of AKI and that ISG20 importantly participates in the degradation of oxidized RNA, suggesting that targeting ISG20-handled RNA oxidation may be an innovative therapeutic strategy for AKI.


Assuntos
Injúria Renal Aguda , Traumatismo por Reperfusão , Animais , Humanos , Camundongos , Injúria Renal Aguda/genética , Injúria Renal Aguda/terapia , Apoptose , Exorribonucleases/genética , Exorribonucleases/metabolismo , Interferons/metabolismo , Isquemia/metabolismo , Rim/metabolismo , Traumatismo por Reperfusão/genética , Traumatismo por Reperfusão/complicações , Traumatismo por Reperfusão/metabolismo , RNA/metabolismo
6.
Hepatology ; 76(5): 1466-1481, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35102596

RESUMO

BACKGROUND AND AIMS: NASH is associated with high levels of cholesterol and triglyceride (TG) in the liver; however, there is still no approved pharmacological therapy. Synthesis of cholesterol and TG is controlled by sterol regulatory element-binding protein (SREBP), which is found to be abnormally activated in NASH patients. We aim to discover small molecules for treating NASH by inhibiting the SREBP pathway. APPROACH AND RESULTS: Here, we identify a potent SREBP inhibitor, 25-hydroxylanosterol (25-HL). 25-HL binds to insulin-induced gene (INSIG) proteins, stimulates the interaction between INSIG and SCAP, and retains them in the endoplasmic reticulum, thereby suppressing SREBP activation and inhibiting lipogenesis. In NASH mouse models, 25-HL lowers levels of cholesterol and TG in serum and the liver, enhances energy expenditure to prevent obesity, and improves insulin sensitivity. 25-HL dramatically ameliorates hepatic steatosis, inflammation, ballooning, and fibrosis through down-regulating the expression of lipogenic genes. Furthermore, 25-HL exhibits both prophylactic and therapeutic efficacies of alleviating NASH and atherosclerosis in amylin liver NASH model diet-treated Ldlr-/- mice, and reduces the formation of cholesterol crystals and associated crown-like structures of Kupffer cells. Notably, 25-HL lowers lipid contents in serum and the liver to a greater extent than lovastatin or obeticholic acid. 25-HL shows a good safety and pharmacokinetics profile. CONCLUSIONS: This study provides the proof of concept that inhibiting SREBP activation by targeting INSIG to lower lipids could be a promising strategy for treating NASH. It suggests the translational potential of 25-HL in human NASH and demonstrates the critical role of SREBP-controlled lipogenesis in the progression of NASH by pharmacological inhibition.


Assuntos
Insulinas , Hepatopatia Gordurosa não Alcoólica , Humanos , Camundongos , Animais , Hepatopatia Gordurosa não Alcoólica/tratamento farmacológico , Hepatopatia Gordurosa não Alcoólica/metabolismo , Lipogênese/fisiologia , Proteínas de Ligação a Elemento Regulador de Esterol , Proteína de Ligação a Elemento Regulador de Esterol 1/metabolismo , Polipeptídeo Amiloide das Ilhotas Pancreáticas/metabolismo , Fígado/metabolismo , Triglicerídeos/metabolismo , Colesterol/metabolismo , Lovastatina/metabolismo , Insulinas/metabolismo , Camundongos Endogâmicos C57BL
7.
Pharmacol Res ; 198: 107009, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37995896

RESUMO

Although hyperhomocysteinemia (hHcys) has been recognized as an important independent risk factor in the progression of end-stage renal disease and the development of cardiovascular complications related to end-stage renal disease, the mechanisms triggering pathogenic actions of hHcys are not fully understood. The present study was mainly designed to investigate the role of HDACs in renal injury induced by hHcys. Firstly, we identified the expression patterns of HDACs and found that, among zinc-dependent HDACs, HDAC9 was preferentially upregulated in the kidney from mice with hHcys. Deficiency or pharmacological inhibition of HDAC9 ameliorated renal injury in mice with hHcys. Moreover, podocyte-specific deletion of HDAC9 significantly attenuated podocyte injury and proteinuria. In vitro, gene silencing of HDAC9 attenuated podocyte injury by inhibiting apoptosis, reducing oxidative stress and maintaining the expressions of podocyte slit diaphragm proteins. Mechanically, we proved for the first time that HDAC9 reduced the acetylation level of H3K9 in the promoter of Klotho, then inhibited gene transcription of Klotho, finally aggravating podocyte injury in hHcys. In conclusion, our results indicated that targeting of HDAC9 might be an attractive therapeutic strategy for the treatment of renal injury induced by hHcys.


Assuntos
Hiper-Homocisteinemia , Falência Renal Crônica , Podócitos , Animais , Camundongos , Repressão Epigenética , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Hiper-Homocisteinemia/genética , Hiper-Homocisteinemia/complicações , Hiper-Homocisteinemia/metabolismo , Falência Renal Crônica/complicações , Falência Renal Crônica/genética , Falência Renal Crônica/metabolismo , Podócitos/patologia
8.
Acta Pharmacol Sin ; 44(6): 1206-1216, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36635422

RESUMO

Hypertensive nephropathy (HTN) ranks as the second-leading cause of end-stage renal disease (ESRD). Accumulating evidence suggests that persistent hypertension injures tubular cells, leading to tubulointerstitial fibrosis (TIF), which is involved in the pathogenesis of HTN. G protein-coupled receptors (GPCRs) are implicated in many important pathological and physiological processes and act as important drug targets. In this study, we explored the intrarenal mechanisms underlying hypertension-associated TIF, and particularly, the potential role of GPR97, a member of the adhesion GPCR subfamily, in TIF. A deoxycorticosterone acetate (DOCA)/salt-induced hypertensive mouse model was used. We revealed a significantly upregulated expression of GPR97 in the kidneys, especially in renal tubules, of the hypertensive mice and 10 patients with biopsy-proven hypertensive kidney injury. GPR97-/- mice showed markedly elevated blood pressure, which was comparable to that of wild-type mice following DOCA/salt treatment, but dramatically ameliorated renal injury and TIF. In NRK-52E cells, we demonstrated that knockdown of GPR97 suppressed the activation of TGF-ß signaling by disturbing small GTPase RhoA-mediated cytoskeletal reorganization, thus inhibiting clathrin-mediated endocytosis of TGF-ß receptors and subsequent Smad activation. Collectively, this study demonstrates that GPR97 contributes to hypertension-associated TIF at least in part by facilitating TGF-ß signaling, suggesting that GPR97 is a pivotal intrarenal factor for TIF progression under hypertensive conditions, and therapeutic strategies targeting GPR97 may improve the outcomes of patients with HTN.


Assuntos
Acetato de Desoxicorticosterona , Hipertensão Renal , Hipertensão , Camundongos , Animais , Acetato de Desoxicorticosterona/efeitos adversos , Rim/patologia , Hipertensão Renal/tratamento farmacológico , Hipertensão Renal/metabolismo , Hipertensão Renal/patologia , Hipertensão/tratamento farmacológico , Fator de Crescimento Transformador beta/metabolismo , Fibrose
9.
Artigo em Inglês | MEDLINE | ID: mdl-38064604

RESUMO

Objective: To investigate the effects of task-oriented biomechanical sensors-balance training on lower limb motor function and gait balance function in stroke patients with hemiplegia. Methods: Researchers divided 106 stroke patients with hemiplegia into observation and control groups. All received essential rehabilitation training treatment. The observation group's rehabilitation consisted of task-oriented biomechanical sensors-balance training. The modified Ashworth Scale score, FuGL-Meyer Motor Function Scale score, and other indicators measured the results of the two groups. Results: The Berg balance scale score and FuGL-Meyer Motor Function Scale score in the observation group were higher than in the control group (P < .05). The modified Ashworth Scale score of the triceps calf muscle in the observation group was significantly lower than that in the control group (P < .05). The observation group's step length, step frequency, maximum angle of hip extension, and knee flexion exceeded those of the control group. In contrast, the maximum angle of knee extension was smaller than those in the control group (P < .05). Conclusion: Basic rehabilitation training combined with task-oriented biomechanical perception-balance training can improve the lower limb motor function of stroke patients with hemiplegia.

10.
Angiogenesis ; 25(4): 455-470, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-35704148

RESUMO

With recent progress in modeling liver organogenesis and regeneration, the lack of vasculature is becoming the bottleneck in progressing our ability to model human hepatic tissues in vitro. Here, we introduce a platform for routine grafting of liver and other tissues on an in vitro grown microvascular bed. The platform consists of 64 microfluidic chips patterned underneath a 384-well microtiter plate. Each chip allows the formation of a microvascular bed between two main lateral vessels by inducing angiogenesis. Chips consist of an open-top microfluidic chamber, which enables addition of a target tissue by manual or robotic pipetting. Upon grafting a liver microtissue, the microvascular bed undergoes anastomosis, resulting in a stable, perfusable vascular network. Interactions with vasculature were found in spheroids and organoids upon 7 days of co-culture with space of Disse-like architecture in between hepatocytes and endothelium. Veno-occlusive disease was induced by azathioprine exposure, leading to impeded perfusion of the vascularized spheroid. The platform holds the potential to replace animals with an in vitro alternative for routine grafting of spheroids, organoids, or (patient-derived) explants.


Assuntos
Microfluídica , Organoides , Animais , Azatioprina , Técnicas de Cocultura , Humanos , Fígado , Microfluídica/métodos
11.
BMC Infect Dis ; 22(1): 945, 2022 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-36526986

RESUMO

BACKGROUND: Central nervous system candidiasis due to Candida albicans (CNSC) in children is easily misdiagnosed and is associated with poor outcomes and a high mortality rate. There is no big data research or systematic review of CNSC. METHODS: Patients diagnosed as CNSC with positive culture results of Candida albicans in Beijing Children's Hospital affiliated to Capital Medical University from March 2010 to March 2019 were included. Patients receiving immunosuppressive therapy or transplantation, or with malignant tumours were excluded. We analysed the clinical characteristics, follow-up results, drug susceptibility tests and whole-exome sequencing (WES) results. RESULTS: Thirty-three definitive patients were enrolled, including 22 males and 11 females. Twenty-five patients suffered from CNSC when they were less than 1 year old, and a total of 29 patients had high-risk factors. The main clinical manifestations were fever, convulsions, and positive neurological signs. Twenty-two patients had CNS infections alone, and 11 patients had CNS infections combined with invasive infections involving multiple sites. Twenty-seven cases had a positive CSF and/or blood culture at our hospital. All strains were susceptible to fluconazole, and 2 strains had intermediate susceptibility to voriconazole. As for amphotericin B, all the strains were wild type (WT). WES of 16 patients revealed 2 cases with CARD9 mutations, who suffered from recurrent onychomycosis or thrush before. CONCLUSION: CNSC mostly existed in children younger than 1 year old, who all had underlying risk factors. CNSC patients with onset at an older age or with recurrent superficial fungal infections might have primary immunodeficiency.


Assuntos
Candidíase , Infecções Fúngicas do Sistema Nervoso Central , Masculino , Feminino , Humanos , Criança , Lactente , Candida albicans/genética , Antifúngicos/uso terapêutico , Antifúngicos/farmacologia , Candidíase/microbiologia , Fluconazol/uso terapêutico , Infecções Fúngicas do Sistema Nervoso Central/diagnóstico , Infecções Fúngicas do Sistema Nervoso Central/tratamento farmacológico , Sistema Nervoso Central , Testes de Sensibilidade Microbiana , Farmacorresistência Fúngica
12.
Virol J ; 17(1): 166, 2020 10 29.
Artigo em Inglês | MEDLINE | ID: mdl-33121509

RESUMO

BACKGROUND: Chronic active Epstein-Barr virus (CAEBV) infection is a type of lymphoproliferative disorder characterized by chronic or recurrent infectious mononucleosis (IM)-like symptoms, which can have less-frequent clinical presentations. The prognosis of CAEBV is poor, and hematopoietic stem cell transplantation (HSCT) has been shown to be the only potentially effective treatment. In this article, we present a special CAEBV case of a patient who had no typical IM-like symptoms at the early stage, but manifested with severe and progressive coronary artery aneurysm (CAA), abdominal aortic lesions, and severe uveitis. These manifestations were uncommon features and could only be blocked by HSCT. CASE PRESENTATION: A 4-year-old girl with no special medical history complained of decreased vision for 10 months and cough after physical activities for three months. The blurred vision grew rapidly worse within one month, until only light perception remained. She was diagnosed with uveitis and cataract, and received prednisone and ciclosporin A treatment. However, her vision did not improve. Physical examination showed slight hepatosplenomegaly. Ultrasonic cardiogram showed bilateral CAA (5.0 mm and 5.7 mm for inner diameters), and abdominal CT scan revealed a thickened aortic wall, as well as stenosis and dilation of the segmental abdominal aorta. Other significant findings were increased EBV-DNA (3.29 × 104 copies/mL) from peripheral blood, positive EBV antibodies (EBV-CA-IgG, EBV-EA-IgA, and EBV-NA-IgG), and positive EBV-encoded small RNAs found by bone marrow biopsy. Based on her clinical manifestations and evidence for EBV infection, we diagnosed CAEBV. She received allogeneic HSCT, and the cataract operation was performed after HSCT. EBV-DNA could not be detected in peripheral blood after HSCT. Her CAAs did not progress, and uveitis was well controlled. Her vision recovered gradually over the 3 years after HSCT. CONCLUSIONS: We present a rare CAEBV case of a patient who suffered from uncommon and severe cardiovascular and ocular involvement that was relieved by HSCT. Therefore, early recognition and diagnosis of CAEBV are of vital importance to improve its prognosis. In summary, this atypical CAEBV case could help us recognize similar cases more easily, make the right diagnosis as early as possible, and deliver proper and timely treatment.


Assuntos
Aneurisma Coronário/virologia , Infecções por Vírus Epstein-Barr/diagnóstico , Herpesvirus Humano 4/patogenicidade , Uveíte/virologia , Anticorpos Antivirais/sangue , Pré-Escolar , Doença Crônica , Aneurisma Coronário/diagnóstico por imagem , Infecções por Vírus Epstein-Barr/complicações , Infecções por Vírus Epstein-Barr/virologia , Feminino , Herpesvirus Humano 4/imunologia , Herpesvirus Humano 4/isolamento & purificação , Humanos , Prognóstico , Tomografia Computadorizada por Raios X , Resultado do Tratamento , Visão Ocular
13.
BMC Infect Dis ; 19(1): 495, 2019 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-31164085

RESUMO

BACKGROUND: There is currently no research on the diagnostic value of metagenomic next-generation sequencing (mNGS) for a single pathogens in CSF. The aim of this study was to analyse the value of mNGS for identifying Streptococcus pneumoniae (S. pneumoniae) in paediatric bacterial meningitis. METHODS: Bacterial meningitis (BM) cases from October 23, 2014, to December 31, 2016, and December 1, 2017, to July 31, 2018 at Beijing Children's Hospital were reviewed. Clinical features and pathogens were analysed. RESULTS: We diagnosed 135 patients with BM in this study. A total of 43 S. pneumoniae were identified by combination methods. 26/135 (19.3%) patients had positive results in S. pneumoniae by blood and/or cerebrospinal fluid (CSF) culture. Alere BinaxNow®Streptococcus pneumoniae Antigen test was positive in 35/135(25.9%) cases. 32/135 (23.7%) S. pneumoniae were identified by mNGS. Six CSF samples were identified as S. pneumoniae only by mNGS technology. Taking culture as the gold standard, the sensitivity and specificity of mNGS for diagnosing S. pneumoniae meningitis were 73.1 and 88.1%, respectively. The positive predictive value (PPV) and negative predictive value (NPV) of diagnosing S. pneumoniae meningitis by mNGS were 59.4 and 93.2%, respectively. When comparison between mNGS and combined tests (culture and Alere BinaxNow®Streptococcus pneumoniae Antigen test), the sensitivity and specificity of mNGS for S. pneumoniae identification were 70.3 and 93.9%, the PPV and NPV in the identification of S. pneumoniae by mNGS were 81.4 and 89.3%, respectively. The difference in number of unique reads of S. pneumoniaein from CSF sample (< 14 days onset) and CSF sample (> 14 days from onset) was statistically significant (170.5 VS. 13, P = 0.019). The difference in the collected time of CSF for culture and mNGS was statistically significant (4 days VS. 14 days, P < 0.001). CONCLUSIONS: mNGS has high sensitivity and specificity for S. pneumoniae identification. The pathogen load (number of unique reads) of S. pneumonia is related to the CSF collection time. mNGS was less affected than culture by the use of antibiotics before CSF collection.


Assuntos
Sequenciamento de Nucleotídeos em Larga Escala , Meningites Bacterianas/diagnóstico , Metagenômica/métodos , Streptococcus pneumoniae/genética , Streptococcus pneumoniae/isolamento & purificação , Adolescente , Fatores Etários , Antígenos de Bactérias/análise , Antígenos de Bactérias/sangue , Antígenos de Bactérias/líquido cefalorraquidiano , Antígenos de Bactérias/genética , Criança , Pré-Escolar , Testes Diagnósticos de Rotina , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Meningites Bacterianas/sangue , Meningites Bacterianas/líquido cefalorraquidiano , Meningites Bacterianas/microbiologia , Pediatria/métodos , Reação em Cadeia da Polimerase/métodos , Valor Preditivo dos Testes , Sensibilidade e Especificidade
14.
Hum Mol Genet ; 24(3): 853-64, 2015 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-25274780

RESUMO

CUL4A and CUL4B are closely related cullin family members and can each assemble a Cullin-RING E3 ligase complex (CRL) and participate in a variety of biological processes. While the CRLs formed by the two cullin members may have common targets, the two appeared to have very different consequences when mutated or disrupted in mammals. We here investigated the roles of cul4a and cul4b during zebrafish embryogenesis by using the morpholino knockdown approach. We found that cul4a is essential for cardiac development as well as for pectoral fin development. Whereas cul4a morphants appeared to be unperturbed in chamber specification, they failed to undergo heart looping. The failures in heart looping and pectoral fin formation in cul4a morphants were accompanied by greatly reduced proliferation of cardiac cells and pectoral fin-forming cells. We demonstrated that tbx5a, a transcription factor essential for heart and limb development, is transcriptionally upregulated by cul4a and mediates the function of cul4a in cardiac and pectoral fin development. In contrast to the critical importance of cul4a, cul4b appeared to be dispensable for zebrafish development and was incapable of compensating for the loss of cul4a. This work provides the first demonstration of an essential role of cul4a, but not cul4b, in cardiac development and in the regulation of tbx5a in zebrafish. These findings justify exploring the functional role of CUL4A in human cardiac development.


Assuntos
Proteínas Culina/metabolismo , Membro Anterior/crescimento & desenvolvimento , Coração/crescimento & desenvolvimento , Proteínas com Domínio T/metabolismo , Proteínas de Peixe-Zebra/metabolismo , Peixe-Zebra/embriologia , Animais , Proliferação de Células , Regulação da Expressão Gênica no Desenvolvimento , Técnicas de Silenciamento de Genes , Cardiopatias Congênitas/metabolismo , Miócitos Cardíacos/metabolismo , Peixe-Zebra/metabolismo
15.
Hum Mol Genet ; 24(16): 4686-97, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-26025376

RESUMO

Astrocytes are the most abundant cell type in the mammalian brain and are important for the functions of the central nervous system. Glial fibrillary acidic protein (GFAP) is regarded as a hallmark of mature astrocytes, though some GFPA-positive cells may act as neural stem cells. Missense heterozygous mutations in GFAP cause Alexander disease that manifests leukodystrophy and intellectual disability. Here, we show that CUL4B, a scaffold protein that assembles E3 ubiquitin ligase, represses the expression of GFAP in neural progenitor cells (NPCs) during brain development. Lack of Cul4b in NPCs in cultures led to increased generation of astrocytes, marked by GFAP and S100ß. The GFAP+ cells were also found to be more abundant in the brains of nervous system-specific Cul4b knockout mice in vivo. Moreover, we demonstrated that the increased generation of GFAP+ cells from Cul4b-null NPCs was mediated by an upregulation of prostaglandin D2 synthase PTGDS. We showed that the increased GFAP expression can be attenuated by pharmacological inhibition of the PTGDS enzymatic activity or by shRNA-mediated knockdown of Ptgds. Importantly, exogenously added PTGDS could promote the generation of GFAP+ cells from wild-type NPCs. We further observed that Ptgds is targeted and repressed by the CUL4B/PRC2 complex. Together, our results demonstrate CUL4B as a negative regulator of GFAP expression during neural development.


Assuntos
Encéfalo/metabolismo , Proteínas Culina/metabolismo , Oxirredutases Intramoleculares/biossíntese , Lipocalinas/biossíntese , Proteínas do Tecido Nervoso/biossíntese , Células-Tronco Neurais/metabolismo , Animais , Encéfalo/citologia , Proteínas Culina/genética , Técnicas de Silenciamento de Genes , Proteína Glial Fibrilar Ácida , Oxirredutases Intramoleculares/genética , Lipocalinas/genética , Camundongos , Camundongos Transgênicos , Proteínas do Tecido Nervoso/genética , Células-Tronco Neurais/citologia
16.
J Cell Sci ; 127(Pt 21): 4679-91, 2014 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-25189618

RESUMO

CUL4B, a scaffold protein that assembles the CRL4B ubiquitin ligase complex, participates in the regulation of a broad spectrum of biological processes. Here, we demonstrate a crucial role of CUL4B in driving cell cycle progression. We show that loss of CUL4B results in a significant reduction in cell proliferation and causes G1 cell cycle arrest, accompanied by the upregulation of the cyclin-dependent kinase (CDK) inhibitors (CKIs) p21 and p57 (encoded by CDKN1A and CDKN1C, respectively). Strikingly, CUL4B was found to negatively regulate the function of p21 through transcriptional repression, but not through proteolysis. Furthermore, we demonstrate that CRL4B and SIN3A-HDAC complexes interact with each other and co-occupy the CDKN1A and CDKN1C promoters. Lack of CUL4B led to a decreased retention of SIN3A-HDAC components and increased levels of acetylated H3 and H4. Interestingly, the ubiquitylation function of CRL4B is not required for the stable retention of SIN3A-HDAC on the promoters of target genes. Thus, in addition to directly contributing to epigenetic silencing by catalyzing H2AK119 monoubiquitylation, CRL4B also facilitates the deacetylation function of SIN3A-HDAC. Our findings reveal a coordinated action between CRL4B and SIN3A-HDAC complexes in transcriptional repression.


Assuntos
Proteínas Culina/metabolismo , Inibidor de Quinase Dependente de Ciclina p21/metabolismo , Proteínas Repressoras/metabolismo , Animais , Ciclo Celular/genética , Ciclo Celular/fisiologia , Proteínas de Ciclo Celular/genética , Proteínas de Ciclo Celular/metabolismo , Proliferação de Células/genética , Proliferação de Células/fisiologia , Proteínas Culina/genética , Inibidor de Quinase Dependente de Ciclina p21/genética , Feminino , Células HeLa , Histona Desacetilases/genética , Histona Desacetilases/metabolismo , Humanos , Imunoprecipitação , Masculino , Camundongos , Ligação Proteica , Reação em Cadeia da Polimerase em Tempo Real , Proteínas Repressoras/genética , Complexo Correpressor Histona Desacetilase e Sin3
17.
J Pathol ; 235(5): 784-95, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25430888

RESUMO

Activation of Wnt/ß-catenin signalling is frequently observed in many types of cancer including hepatocellular carcinoma (HCC). We recently reported that cullin 4B (CUL4B), a scaffold protein that assembles CRL4B ubiquitin ligase complexes, is overexpressed in many types of solid tumours and contributes to epigenetic silencing of tumour suppressors. In this study, we characterized the function of CUL4B in HCC and investigated whether CUL4B is involved in the regulation of Wnt/ß-catenin signalling. CUL4B and ß-catenin were frequently up-regulated and positively correlated in HCC tissues. CUL4B activated Wnt/ß-catenin signalling by protecting ß-catenin from GSK3-mediated degradation, achieved through CUL4B-mediated epigenetic silencing of Wnt pathway antagonists. Knockdown of CUL4B resulted in the up-regulation of Wnt signal antagonists such as DKK1 and PPP2R2B. Simultaneous knockdown of PPP2R2B partially reversed the down-regulation of ß-catenin signalling caused by CUL4B depletion. Furthermore, CRL4B promoted the recruitment and/or retention of PRC2 at the promoters of Wnt antagonists and CUL4B knockdown decreased the retention of PRC2 components as well as H3K27me3. Knockdown of CUL4B reduced the proliferation, colony formation, and invasiveness of HCC cells in vitro and inhibited tumour growth in vivo, and these effects were attenuated by introduction of exogenous ß-catenin or simultaneous knockdown of PPP2R2B. Conversely, ectopic expression of CUL4B enhanced the proliferation and invasiveness of HCC cells. We conclude that CUL4B can up-regulate Wnt/ß-catenin signalling in human HCC through transcriptionally repressing Wnt antagonists and thus contributes to the malignancy of HCC.


Assuntos
Carcinoma Hepatocelular/enzimologia , Proteínas Culina/metabolismo , Neoplasias Hepáticas/enzimologia , Via de Sinalização Wnt , beta Catenina/metabolismo , Carcinoma Hepatocelular/genética , Carcinoma Hepatocelular/patologia , Movimento Celular , Proliferação de Células , Proteínas Culina/genética , Regulação para Baixo , Regulação Neoplásica da Expressão Gênica , Quinase 3 da Glicogênio Sintase/metabolismo , Células Hep G2 , Humanos , Neoplasias Hepáticas/genética , Neoplasias Hepáticas/patologia , Invasividade Neoplásica , Proteínas do Tecido Nervoso/genética , Proteínas do Tecido Nervoso/metabolismo , Proteína Fosfatase 2/genética , Proteína Fosfatase 2/metabolismo , Proteólise , Fatores de Tempo , Transcrição Gênica , Transfecção , Carga Tumoral , beta Catenina/genética
18.
Zhongguo Dang Dai Er Ke Za Zhi ; 16(8): 834-9, 2014 Aug.
Artigo em Zh | MEDLINE | ID: mdl-25140778

RESUMO

OBJECTIVE: To study the clinical value of cranial magnetic resonance imaging (MRI) in the diagnosis and treatment of central nervous system candidiasis (CNSC), which has no specific clinical manifestations and has no rapid and specific diagnostic tools. METHODS: A retrospective analysis was performed on the clinical data of 10 children who were diagnosed with CNSC in Beijing Children's Hospital Affiliated to Capital Medical University between 2009 and 2013. RESULTS: Nine of the 10 children underwent cranial MRI within 8 days after admission, and 5 of the 9 children underwent contrast-enhanced MRI at the same time. Eight of the 9 children showed the features of meningoencephalitis, and 6 cases were accompanied by varying degrees of brain atrophy; one case showed hydrocephalus and cerebral abscess, and another case showed leukoencephalopathy. Six cases were found to have the features of cerebral vasculitis after infection in the first MRI after admission, including cerebral infarction (2 cases), venous sinus thrombosis (3 cases), and Moyamoya disease (1 case). Infectious granulomatous lesions were confirmed by contrast-enhanced MRI in 3 cases. Given the clinical manifestations, 8 of the 9 cases were diagnosed as suspected CNSC after MRI, and 7 of these cases received antifungal therapy before the pathogen test results were returned. The lesions on MRI were improved in 6 cases after 3-4 weeks of antifungal treatment. All the 10 children were diagnosed with CNSC by positive cerebrospinal fluid culture results. CONCLUSIONS: Cranial MRI, especially contrast-enhanced MRI, is of great significance for the diagnosis and treatment of CNSC. To confirm the guidance of MRI in the diagnosis and treatment of CNSC, further case-control studies are needed.


Assuntos
Candidíase/diagnóstico , Infecções Fúngicas do Sistema Nervoso Central/diagnóstico , Imageamento por Ressonância Magnética/métodos , Candidíase/patologia , Infecções Fúngicas do Sistema Nervoso Central/patologia , Criança , Pré-Escolar , Feminino , Humanos , Lactente , Masculino , Estudos Retrospectivos
19.
Cancer Lett ; 598: 217122, 2024 Aug 28.
Artigo em Inglês | MEDLINE | ID: mdl-39029781

RESUMO

Tumor organoids have emerged as a crucial preclinical model for multiple cancer research. Their high establishment rates, stability, and ability to replicate key biological features of original tumor cells in vivo render them invaluable for exploring tumor molecular mechanisms, discovering potential anti-tumor drugs, and predicting clinical drug efficacy. Here, we review the establishment of tumor organoid models and provide an extensive overview of organoid culturing strategies. We also emphasize the significance of integrating cellular components of the tumor microenvironment and physicochemical factors in the organoid culturing system, highlighting the importance of artificial intelligence technology in advancing organoid construction. Moreover, we summarize recent advancements in utilizing organoid systems for novel anti-cancer drug screening and discuss promising trends for enhancing advanced organoids in next-generation disease modeling.


Assuntos
Neoplasias , Organoides , Microambiente Tumoral , Organoides/efeitos dos fármacos , Organoides/patologia , Humanos , Neoplasias/patologia , Neoplasias/tratamento farmacológico , Animais , Inteligência Artificial , Ensaios de Seleção de Medicamentos Antitumorais/métodos , Antineoplásicos/farmacologia
20.
Waste Manag ; 187: 207-217, 2024 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-39059157

RESUMO

Seaweed waste, abundant and rich in plant-stimulating properties, has the potential to be transformed into valuable soil amendments through proper composting and utilization management. Given its low carbon-to-nitrogen ratio, co-composting seaweed with carbon-rich cornstarch dregs is an effective strategy. However, the potential application of co-composting largely depends on the efficiency of the composting and the quality of the product. This study explores the effects of adding 10 % corn stalk biochar to a co-composting system of seaweed and cornstarch dregs, alongside varying buffering capacities of phosphates (KH2PO4 and K2HPO4·3H2O-KH2PO4) and MgO, on the degradation efficiency of organic matter, nitrogen transformation, and humification. The results indicate that the addition of biochar and salts enhances the oxygen utilization rate (OUR) and cellulase activity during the thermophilic phase. Additionally, X-ray diffraction (XRD) and parallel factor analysis (PARAFAC) demonstrate more intense solubilization and transformation of proteinaceous substances, along with cellulose degradation. These processes are crucial for enhancing organic matter degradation and humification, significantly boosting degradation (with an increase of 28.6 % to 33.8 %) and humification levels (HA/FA increased by 37.1 % to 49.6 %). Specifically, groups with high buffering capacity significantly promote the formation of NO3--N and NH4+-N, and a higher degree of humification, creating an optimal environment for significantly improving nitrogen retention (increased by 4.80 %). Additionally, this treatment retains and slightly enhances the plant-stimulating properties of seaweed. These findings underscore the potential of integrating biochar with specific ratios of phosphates and MgO to enhance composting efficiency and product quality while preserving the plant-stimulating effects of seaweed.


Assuntos
Carvão Vegetal , Compostagem , Óxido de Magnésio , Nitrogênio , Fosfatos , Alga Marinha , Alga Marinha/química , Carvão Vegetal/química , Óxido de Magnésio/química , Compostagem/métodos , Zea mays , Amido/química , Substâncias Húmicas/análise , Solo/química
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