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1.
Adv Ther ; 2021 Mar 17.
Artigo em Inglês | MEDLINE | ID: mdl-33730351

RESUMO

INTRODUCTION: The present study aimed to investigate the effect of anti-cytomegalovirus (anti-CMV) therapy at different stages on retinal detachment in patients with acquired immunodeficiency syndrome (AIDS) and cytomegalovirus retinitis (CMVR). METHODS: Ninety-seven patients with AIDS and CMVR diagnosed and treated at the Ophthalmology and Infection Center of Beijing You'an Hospital, affiliated with Capital Medical University, from November 2017 to January 2020 were retrospectively analyzed. Of the 138 eyes included, 30 eyes with concomitant retinal detachment were enrolled as the study subjects. The eyes with retinal detachment were divided into a pre-induction group, an intra-induction group, and a post-induction group of anti-CMV therapy. The occurrence and characteristics of retinal detachment at different stages of anti-CMV therapy were observed. RESULTS: Retinal detachment occurred in 30 of the 138 eyes of 97 patients, with an incidence of retinal detachment of 21.74%. Retinal detachment occurred in eight eyes in the pre-induction group, with an incidence of 26.67%, and in four eyes in the intra-induction group, with an incidence of 13.33%. The difference in incidence between the two groups was statistically significant (P = 0.000). Retinal detachment occurred in 18 eyes in the post-induction group, with an incidence of 60%. The difference in incidence between the intra-induction group and the post-induction group was statistically significant (P = 0.001). CONCLUSION: The incidence of retinal detachment at the intra-induction stages of anti-CMV therapy was lower than that at the pre-induction stage, and retinal detachment during the anti-CMV therapy predominantly occurred after the end of the induction stage.

2.
J Med Ultrason (2001) ; 48(1): 53-61, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33439373

RESUMO

PURPOSE: To evaluate tissue stiffness values around breast lesions and stiff rim sign for the differentiation of benign and malignant lesions. METHODS: A total of 192 patients (mean age, 44.6 ± 13.6 years) with 199 breast lesions were included in this retrospective study. All lesions were pathologically proven by US-guided core needle biopsy (CNB), Mammotome biopsy, or surgery. We first observed the presence or absence of a stiff rim sign, which was defined as a red or orange halo around the breast lesion. The shell around the breast lesion on SWE was then automatically drawn by machine, with a width of 1 mm, 2 mm, and 3 mm. The elasticity moduli of the lesion and surrounding tissue were recorded, including maximum elasticity (Emax), mean elasticity (Emean), minimum elasticity (Emin), and elasticity ratio (shell/lesion ratio). The optimal thresholds of elasticity moduli were calculated according to the receiver operating characteristic (ROC) curve. RESULTS: There were 75 malignant lesions and 124 benign ones. The average Emax and Emean of lesions and shell were significantly higher in the malignant group than in the benign group (P < 0.05). The optimal cut-off value of Emax for diagnosing malignant lesions was 101.7 kPa, with a sensitivity of 66.3% and specificity of 87.9%. The optimal cut-off value of Emean was 29.1 kPa, with a sensitivity of 65.3% and specificity of 79.8%. The stiff rim sign had the highest diagnostic performance for malignancy as compared with other elastic parameters, with an accuracy of 88.4%. However, measuring peritumoral tissue stiffness can achieve relatively high sensitivity, whereas specificity was not improved significantly. CONCLUSIONS: The stiffness of tissue surrounding breast malignancies was significantly higher than the surrounding benign lesions. Stiff rim sign has the potential to improve the diagnostic performance of breast lesions.

3.
Kaohsiung J Med Sci ; 37(4): 305-313, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33508890

RESUMO

Peritoneal metastasis (PM) is the major cause of recurrence in patients with gastric cancer (GC) and is associated with poor prognosis. The oncogenic role of Nicotinamide N-methyltransferase (NNMT) in GC has been reported, but the role of secreted NNMT that is transported by exosomes remains unknown. In this study, exosomes were isolated from GC patients with or without PM and from GC cell line, including GC-114, GC-026, MKN45, and SNU-16 cells. The contents of NNMT were significantly enhanced in exosomes isolated from GC patients with PM compared with those from GC patients without PM. Furthermore, the levels of NNMT were significantly enhanced in exosomes from GC cell lines relative to those from normal human gastric epithelial cell line GES-1 cells. These data indicate that NNMT may be involved in intercellular communication for peritoneal dissemination. Moreover, colocalization of GC-derived exosomal NNMT was found in human peritoneal mesothelial cell line HMrSV5 cells. Additionally, relative to GES-1 exosomes, SNU-16 exosomes significantly activated TGF-ß/smad2 signaling in HMrSV5 cells. However, when NNMT was silenced, the activation of TGF-ß/smad2 by SNU-16 exosomes was abolished in HMrSV5 cells. We propose that NNMT-containing exosomes derived from GC cells could promote peritoneal metastasis via TGF-ß/smad2 signaling.

4.
Mediators Inflamm ; 2020: 2960517, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33013197

RESUMO

Insulin resistance has been shown to be the common pathogenesis of many metabolic diseases. Metainflammation is one of the important characteristics of insulin resistance. Macrophage polarization mediates the production and development of metainflammation. Toll-like receptor 4 (TLR4) mediates macrophage activity and is probably the intersection of immunity and metabolism, but the detailed mechanism is probably not fully understood. Activated protein 1 (AP1) signaling pathway is very important in macrophage activation-mediated inflammation. However, it is unclear whether AP1 signaling pathway mediates metabolic inflammation in the liver. We aimed to investigate the effects of macrophage TLR4-AP1 signaling pathway on hepatocyte metabolic inflammation, insulin sensitivity, and lipid deposition, as well as to explore the potential of TLR4-AP1 as new intervention targets of insulin resistance and liver steatosis. TLR4 and AP1 were silenced in the RAW264.7 cells by lentiviral siRNA transfection. In vivo transduction of lentivirus was administered in mice fed with high-fat diet. Insulin sensitivity and inflammation were evaluated in the treated cells or animals. Our results indicated that TLR4/AP-1 siRNA transfection alleviated high-fat diet-induced systemic and hepatic inflammation, obesity, and insulin resistance in mice. Additionally, TLR4/AP-1 siRNA transfection mitigated palmitic acid- (PA-) induced inflammation in RAW264.7 cells and metabolic abnormalities in cocultured AML hepatocytes. Herein, we propose that TLR4-AP1 signaling pathway activation plays a crucial role in high fat- or PA-induced metabolic inflammation and insulin resistance in hepatocytes. Intervention of the TLR4 expression regulates macrophage polarization and metabolic inflammation and further alleviates insulin resistance and lipid deposition in hepatocytes.

6.
J Immunol Res ; 2020: 1025857, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33083497

RESUMO

Objective: Fulminant type 1 diabetes (FT1D) is a type of type 1 diabetes, which is characterized by rapid onset of disease and severe metabolic disorders. We intend to screen for crucial genes and potential molecular mechanisms in FT1D in this study. Method: We downloaded GSE44314, which includes six healthy controls and five patients with FT1D, from the GEO database. Identification of differentially expressed genes (DEGs) was performed by NetworkAnalyst. The Gene Ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG) enrichment analyses of DEGs were screened by an online tool-Database for Annotation, Visualization, and Integration Discovery (DAVID). Protein-protein interaction (PPI) network and hub genes among DEGs were analyzed by NetworkAnalyst. And we also use NetworkAnalyst to find out the microRNAs (miRNAs) and transcription factors (TFs) which regulate the expression of DEGs. Result: We identified 130 DEGs (60 upregulated and 70 downregulated DEGs) between healthy controls and FT1D patients. GO analysis results revealed that DEGs were mostly enriched in generation of precursor metabolites and energy, neurohypophyseal hormone activity, and mitochondrial inner membrane. KEGG pathway analysis demonstrated that DEGs were mostly involved in nonalcoholic fatty liver disease. Results indicated that NCOA1, SRF, ERBB3, EST1, TOP1, UBE2S, INO80, COX7C, ITGAV, and COX6C were the top hub genes in the PPI network. Furthermore, we recognized that LDLR, POTEM, IFNAR2, BAZ2A, and SRF were the top hub genes in the miRNA-target gene network, and SRF, TSPAN4, CD59, ETS1, and SLC25A25 were the top hub genes in the TF-target gene network. Conclusion: Our study pinpoints key genes and pathways associated with FT1D by a sequence of bioinformatics analysis on DEGs. These identified genes and pathways provide more detailed molecular mechanisms of FT1D and may provide novel therapeutic targets.

7.
Ophthalmologica ; 2020 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-33120392

RESUMO

PURPOSE: To explore the potential use of ultra-wide-field (UWF) imaging for screening of cytomegalovirus retinitis (CMVR) in AIDS patients. METHODS: Ninety-four patients whose CD4 count was below 200 cells/µl were enrolled in a prospective study. Each patient underwent UWF imaging and indirect ophthalmoscopy. The main outcome measures were the concordance and detection rates of these two approaches and the sensitivity and specificity of UWF imaging. RESULTS: Twenty-seven eyes in 18 patients were diagnosed with CMVR by the indirect ophthalmoscopy. UWF imaging missed the diagnosis in one eye because of a zone 3 CMVR lesion. The UWF image showed several CMVR patterns and locations: hemorrhagic necrotizing lesion, granular lesion, frosted branch angiitis, and optic neuropathy lesion. The concordance of the two approaches was excellent for diagnosis of CMVR, classification of CMVR pattern, and location of CMVR. The detection rates of UWF imaging and indirect ophthalmoscopy were 14.0% (26/186; 95% CI, 0.089-0.190) and 14.5% (27/186; 95% CI, 0.094-0.196), respectively (p = 1.000). The sensitivity and specificity of UWF imaging were 96.3% and 100%, respectively. CONCLUSIONS: UWF imaging is capable of documentation of different CMVR lesions and AIDS-related CMVR screening when examination by an ophthalmologist is not available.

8.
Med Ultrason ; 2020 08 18.
Artigo em Inglês | MEDLINE | ID: mdl-32905565

RESUMO

The aim of this study is to investigate whether the use of contrast enhanced ultrasound (CEUS) can improve the differential diagnostic performance between hepatic inflammatory pseudotumor (HIPT) and other malignant tumors. MATERIAL AND METHODS: Forty-four patients with histological proven HIPTs were included in this retrospective study. The features of conventional ultrasound (US) and CEUS were evaluated. RESULTS: Three kinds of enhanced pattern can be seen in the 44 nodules including homogeneous (n=18, 41%), heterogeneous (n=16, 36%) and rim-like enhancement (n=10, 23%). All of the nodules showed hypo-enhancement during the portal and delayed phase. The dominant nodules (n=29, 66%) presented wash-out within 60 s after contrast injection. Quick wash-in and wash-out was seen in 18 nodules (41%). Eighteen nodules (41%) were correctly diagnosed as HIPT, whereas the remaining 26 cases were misdiagnosed as malignancies (n=20, 45%) or with an uncertain diagnosis (n=6, 14%). CONCLUSION: CEUS was not enough to differentiate HIPT from hepatic malignancies, especially intrahepatic cholangiocarcinoma and liver metastasis. However, some CEUS imaging characteristics may be helpful for HIPT diagnosis.

9.
PLoS One ; 15(9): e0238282, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32915788

RESUMO

The number, intensity and order of emergence of HIV-1 specific antibodies in serum or plasma were associated with the stage of HIV-1 infection. In this study, we retrospectively analyzed the HIV-1 confirmatory results tested by western blot (WB) or recombination immunoblot assay (RIBA) in Wuhan, 2012-2018, to access the profiles of HIV-1 specific antibodies. A total of 14432 HIV-suspected serum or plasma samples collected from local hospitals and other HIV screening laboratories were further screened by two 4th generation enzyme-linked immunosorbent assay (ELISA) kits in our laboratory, of which 11068 specimens (76.69%) had at least one positive ELISA result and thereby were finally confirmed with WB or RIBA. RIBA had identified 652 (81.09%) positive and 13 (1.62%) indeterminate cases from July 1, 2014 to January 7, 2015, while WB had identified 8358 (81.43%) positive and 643 (6.26%) indeterminate cases in the other times during 2012-2018. The indeterminate rate of WB was significant higher than that of RIBA (p<0.001). Although the number of HIV-1 infected subjects increased significantly from 2012 (n = 911) to 2018 (n = 1578), the positive rate of HIV-1 antibodies decreased markedly from 70.08% in 2012 to 58.79% in 2018 (p<0.001). The most commonly observed antibody profile was gp160+gp120+p66+(p55+)p51+gp41+p31+p24+p17+ (4131, 49.43%) for WB-MP and gp160+gp120+gp41+p31+p24+p17+ (382, 58.59%) for RIBA-WANTAI, and the absence of reactivity to three possible serologic markers for recent HIV-1 infection, p31, p66, and p51, increased significantly from 2012 to 2018, with the overall rate of 17.03%, 9.40%, and 15.15%, respectively. The suspected acute HIV-1 infection was also observed to be increased in recent years, with an overall rate of 1.00%. Our results indicated the detection rate had decreased for HIV-1 infection, but increased for suspected recent and acute HIV-1 infection during 2012-2018, reflecting the efforts of intervention among high risk population.


Assuntos
Anticorpos Anti-HIV/sangue , Proteína gp120 do Envelope de HIV/imunologia , Proteína gp160 do Envelope de HIV/imunologia , Infecções por HIV/diagnóstico , Soropositividade para HIV/epidemiologia , HIV-1/imunologia , Adolescente , Adulto , Criança , China/epidemiologia , Ensaio de Imunoadsorção Enzimática , Feminino , Anticorpos Anti-HIV/imunologia , Infecções por HIV/sangue , Infecções por HIV/epidemiologia , HIV-1/isolamento & purificação , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Testes Sorológicos , Fatores de Tempo , Adulto Jovem
10.
Artigo em Inglês | MEDLINE | ID: mdl-32754119

RESUMO

Background: Diabetes correlates with poor prognosis in patients with COVID-19, but very few studies have evaluated whether impaired fasting glucose (IFG) is also a risk factor for the poor outcomes of patients with COVID-19. Here we aimed to examine the associations between IFG and diabetes at admission with risks of complications and mortality among patients with COVID-19. Methods: In this multicenter retrospective cohort study, we enrolled 312 hospitalized patients with COVID-19 from 5 hospitals in Wuhan from Jan 1 to Mar 17, 2020. Clinical information, laboratory findings, complications, treatment regimens, and mortality status were collected. The associations between hyperglycemia and diabetes status at admission with primary composite end-point events (including mechanical ventilation, admission to intensive care unit, or death) were analyzed by Cox proportional hazards regression models. Results: The median age of the patients was 57 years (interquartile range 38-66), and 172 (55%) were women. At the time of hospital admission, 84 (27%) had diabetes (and 36 were new-diagnosed), 62 (20%) had IFG, and 166 (53%) had normal fasting glucose (NFG) levels. Compared to patients with NFG, patients with IFG and diabetes developed more primary composite end-point events (9 [5%], 11 [18%], 26 [31%]), including receiving mechanical ventilation (5 [3%], 6 [10%], 21 [25%]), and death (4 [2%], 9 [15%], 20 [24%]). Multivariable Cox regression analyses showed diabetes was associated increased risks of primary composite end-point events (hazard ratio 3.53; 95% confidence interval 1.48-8.40) and mortality (6.25; 1.91-20.45), and IFG was associated with an increased risk of mortality (4.11; 1.15-14.74), after adjusting for age, sex, hospitals and comorbidities. Conclusion: IFG and diabetes at admission were associated with higher risks of adverse outcomes among patients with COVID-19.


Assuntos
Glicemia/metabolismo , Infecções por Coronavirus/mortalidade , Complicações do Diabetes/mortalidade , Diabetes Mellitus/fisiopatologia , Intolerância à Glucose/complicações , Hiperglicemia/complicações , Pneumonia Viral/mortalidade , Adulto , Idoso , Betacoronavirus/isolamento & purificação , China/epidemiologia , Infecções por Coronavirus/complicações , Infecções por Coronavirus/epidemiologia , Infecções por Coronavirus/virologia , Complicações do Diabetes/epidemiologia , Complicações do Diabetes/virologia , Diabetes Mellitus/virologia , Jejum , Feminino , Seguimentos , Intolerância à Glucose/virologia , Mortalidade Hospitalar , Hospitalização , Humanos , Hiperglicemia/virologia , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/complicações , Pneumonia Viral/epidemiologia , Pneumonia Viral/virologia , Prognóstico , Estudos Retrospectivos , Fatores de Risco , Índice de Gravidade de Doença , Taxa de Sobrevida
11.
Proc Natl Acad Sci U S A ; 117(29): 17418-17428, 2020 07 21.
Artigo em Inglês | MEDLINE | ID: mdl-32636267

RESUMO

Carboxysomes are membrane-free organelles for carbon assimilation in cyanobacteria. The carboxysome consists of a proteinaceous shell that structurally resembles virus capsids and internal enzymes including ribulose 1,5-bisphosphate carboxylase/oxygenase (Rubisco), the primary carbon-fixing enzyme in photosynthesis. The formation of carboxysomes requires hierarchical self-assembly of thousands of protein subunits, initiated from Rubisco assembly and packaging to shell encapsulation. Here we study the role of Rubisco assembly factor 1 (Raf1) in Rubisco assembly and carboxysome formation in a model cyanobacterium, Synechococcus elongatus PCC7942 (Syn7942). Cryo-electron microscopy reveals that Raf1 facilitates Rubisco assembly by mediating RbcL dimer formation and dimer-dimer interactions. Syn7942 cells lacking Raf1 are unable to form canonical intact carboxysomes but generate a large number of intermediate assemblies comprising Rubisco, CcaA, CcmM, and CcmN without shell encapsulation and a low abundance of carboxysome-like structures with reduced dimensions and irregular shell shapes and internal organization. As a consequence, the Raf1-depleted cells exhibit reduced Rubisco content, CO2-fixing activity, and cell growth. Our results provide mechanistic insight into the chaperone-assisted Rubisco assembly and biogenesis of carboxysomes. Advanced understanding of the biogenesis and stepwise formation process of the biogeochemically important organelle may inform strategies for heterologous engineering of functional CO2-fixing modules to improve photosynthesis.


Assuntos
Organelas/metabolismo , Ribulose-Bifosfato Carboxilase/metabolismo , Synechococcus/metabolismo , Carbono/metabolismo , Ciclo do Carbono , Microscopia Crioeletrônica , Regulação Bacteriana da Expressão Gênica , Genes Bacterianos/genética , Modelos Moleculares , Chaperonas Moleculares/metabolismo , Fotossíntese , Subunidades Proteicas/metabolismo , Ribulose-Bifosfato Carboxilase/química , Ribulose-Bifosfato Carboxilase/genética , Synechococcus/genética , Transcriptoma
12.
Virol Sin ; 2020 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-32705575

RESUMO

The immense patient number caused by coronavirus disease 2019 (COVID-19) global pandemic brings the urge for more knowledge about its immunological features, including the profile of basic immune parameters. In this study, eighty-eight reported COVID-19 patients in Wuhan were recruited from January to February, 2020, including 32 severe/critical cases and 56 mild/moderate cases. Their mean age was 56.43 years (range 17-83) and gender ratio (male/female) was 43:45. We tested SARS-CoV-2 RNA with commercial kits, investigated the level of serologic IgM and IgG antibodies against severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) using magnetic particle chemiluminescence immunoassays, and compared the results of serologic tests and nucleic acid test (NAT). Among 88 patients, 95.45% were confirmed as positive by the combination of NAT and antibody test, which was significantly higher (P < 0.001) than by single nucleic acid test (73.86%) or serologic test (65.91%). Then the correlation between temporal profile and the level of antibody response was analyzed. It showed that seroconversion started on day 5 after disease onset and IgG level was rose earlier than IgM. Comparison between patients with different disease severity suggested early seroconversion and high antibody titer were linked with less severe clinical symptoms. These results supported the combination of serologic testing and NAT in routine COVID-19 diagnosis and provided evidence on the temporal profile of antibody response in patients with different disease severity.

13.
Nat Commun ; 11(1): 2135, 2020 05 01.
Artigo em Inglês | MEDLINE | ID: mdl-32358509

RESUMO

A non-immunogenic tumor microenvironment (TME) is a significant barrier to immune checkpoint blockade (ICB) response. The impact of Polybromo-1 (PBRM1) on TME and response to ICB in renal cell carcinoma (RCC) remains to be resolved. Here we show that PBRM1/Pbrm1 deficiency reduces the binding of brahma-related gene 1 (BRG1) to the IFNγ receptor 2 (Ifngr2) promoter, decreasing STAT1 phosphorylation and the subsequent expression of IFNγ target genes. An analysis of 3 independent patient cohorts and of murine pre-clinical models reveals that PBRM1 loss is associated with a less immunogenic TME and upregulated angiogenesis. Pbrm1 deficient Renca subcutaneous tumors in mice are more resistance to ICB, and a retrospective analysis of the IMmotion150 RCC study also suggests that PBRM1 mutation reduces benefit from ICB. Our study sheds light on the influence of PBRM1 mutations on IFNγ-STAT1 signaling and TME, and can inform additional preclinical and clinical studies in RCC.


Assuntos
Carcinoma de Células Renais/tratamento farmacológico , Carcinoma de Células Renais/metabolismo , Proteínas de Ligação a DNA/metabolismo , Neoplasias Renais/tratamento farmacológico , Neoplasias Renais/microbiologia , Fatores de Transcrição/metabolismo , Animais , Complexo Antígeno-Anticorpo/genética , Complexo Antígeno-Anticorpo/metabolismo , Carcinoma de Células Renais/genética , Proteínas de Ligação a DNA/deficiência , Proteínas de Ligação a DNA/genética , Feminino , Imunofluorescência , Regulação Neoplásica da Expressão Gênica/genética , Humanos , Imuno-Histoquímica , Neoplasias Renais/genética , Camundongos , Camundongos Endogâmicos BALB C , Camundongos Knockout , Mutação , Fosforilação , Fator de Transcrição STAT1/metabolismo , Análise Serial de Tecidos , Fatores de Transcrição/deficiência , Fatores de Transcrição/genética , Transcriptoma/genética
14.
Exp Cell Res ; 394(1): 112093, 2020 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-32450067

RESUMO

Regulating proteasome activity is a potent therapeutic aspect of age-related hearing loss, which has been proven to protect neurons from age-related damaging. PSMD11, subunit of the 19S proteasome regulatory particle, is known to mainly up-regulate proteasome activity and prolong aging. However, the mechanism of PSMD11 in age-related hearing loss has not been deeply explored. In the present study, we explore the function and mechanism of PSMD11 protecting neurons in d-Galactose (D-Gal) mimetic aging models. Age-related pathologies were detected by Taq-PCR, ABR, Transmission electron microscopy, toluidine blue and ß-galactosidase staining. The relative expressions of the proteins were explored by Western blotting, oxyblot, immunoprecipitation and immunofluorescence. Flow cytometry was used to manifest the oxidative state. We discovered that proteasome activity was impaired with aging, and that ROS and toxic protein accumulated in D-Gal induced aging models. PSMD11 changed with aging, and was associated with the metabolism of proteasome activity in the D-Gal treated models. Moreover, the knockdown or overexpression of PSMD11 was sufficient to change the oxidative state caused by D-Gal. Our results also demonstrated that PSMD11 could bond to AMPKα1/2 in the auditory cortex and PC12 cells, and AMPKα2 but not AMPKα1 was efficient to regulate the function of PSMD11. Deeper insights into the mechanisms of regulating PSMD11 for the anti-aging process are needed, and may offer novel therapeutic methods for central presbycusis.

15.
Nat Plants ; 6(6): 708-717, 2020 06.
Artigo em Inglês | MEDLINE | ID: mdl-32451445

RESUMO

The folding and assembly of RuBisCO, the most abundant enzyme in nature, needs a series of chaperones, including the RuBisCO accumulation factor Raf1, which is highly conserved in cyanobacteria and plants. Here, we report the crystal structures of Raf1 from cyanobacteria Anabaena sp. PCC 7120 and its complex with RuBisCO large subunit RbcL. Structural analyses and biochemical assays reveal that each Raf1 dimer captures an RbcL dimer, with the C-terminal tail inserting into the catalytic pocket, and further mediates the assembly of RbcL dimers to form the octameric core of RuBisCO. Furthermore, the cryo-electron microscopy structures of the RbcL-Raf1-RbcS assembly intermediates enable us to see a dynamic assembly process from RbcL8Raf18 to the holoenzyme RbcL8RbcS8. In vitro assays also indicate that Raf1 can attenuate and reverse CcmM-mediated cyanobacterial RuBisCO condensation. Combined with previous findings, we propose a putative model for the assembly of cyanobacterial RuBisCO coordinated by the chaperone Raf1.

17.
Clin Infect Dis ; 2020 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-32369577

RESUMO

BACKGROUND: Discordance between QuantiFERON-TB (QFT) Gold In-Tube and tuberculin skin tests (TST) is not well understood. To identify factors that determine discordance between TST and QFT tests when compared to either TST+QFT+ or TST-QFT- results in a medium tuberculosis burden setting. METHODS: We conducted a population-based study in Eastern China and administered TST and QFT tests to participants. We calculated kappa values while constructing multivariable logistic regression models to evaluate predictors of test discordance. We analyzed the predictive value of discordant and concordant test results for progression to tuberculosis over 6 years of follow-up. RESULTS: Overall, 5,405 participants were enrolled; 2,043 (37.8%) and 1,104 (20.4%) were TST and QFT positive. There was fair agreement between the TST and the QFT (kappa values between 0.30-0.39 at different TST cutoffs). Agreement was lower among BCG-vaccinated participants (κ, 0.17 versus 0.47). TST+QFT- results were associated with decreasing age, smoking, undiagnosed diabetes, and BCG vaccination (adjusted Odds Ratio, 1.45, 95%CI, 1.11-1.90). TST-QFT+ results were associated with increasing age, male sex, smoking, and diagnosed diabetes. Compared to participants with TST-QFT- results, QFT+ and TST+QFT+ participants were 6.3 (95%CI, 1.9-20.4) and 7.5 (95%CI, 2.3-25.1) times more likely to progress to tuberculosis. CONCLUSIONS: In this population-based study of over 5000 participants from a medium tuberculosis burden region, test agreement between QFT and TST was fair overall, and we found multiple novel predictors of discordant QFT/TST test results. QFT provides a substantial improvement to the TST among these populations and was multi-fold better predictive of progression to tuberculosis.

18.
World J Gastrointest Oncol ; 12(5): 582-591, 2020 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-32461789

RESUMO

BACKGROUND: Gastric Helicobacter pylori (H. pylori) infection is related to chronic gastritis, gastroduodenal ulcer, and gastric malignancies; whether this infection is related to colorectal polyps and colorectal cancer (CRC), remains debatable. AIM: To investigate the relationship between gastric H. pylori infection and the risk of colorectal polyps and CRC. METHODS: We retrospectively analyzed 3872 patients with colorectal polyps who underwent colonoscopy and pathological diagnosis. We also analyzed 304 patients with primary CRC. The characteristics of these patients were compared with those of the control group, which included 2362 patients with the normal intestinal mucosa. All subjects completed a 14C-urea breath test, bidirectional gastrointestinal endoscopy, and a biopsy on the same day. Data on the number, size, location, and pathology of the polyps, the location, and pathology of the CRC, the detection of H. pylori, and the incidence of H. pylori-associated atrophic gastritis or intestinal metaplasia were obtained. A logistic regression model was used to analyze the relationship between gastric infection due to H. pylori, and the incidence of colorectal polyps and CRC. RESULTS: The prevalence of H. pylori infection was higher in the multiple polyps group than in the solitary polyp group and the control group [95% confidence interval (CI) = 1.02-1.31, P = 0.03; 95%CI: 2.12-2.74, P < 0.001]. The patients with adenomatous polyps had a higher incidence of H. pylori infection than patients with non-adenomatous polyps [59.95% vs 51.75%, adjusted odds ratio (OR) = 1.41, 95%CI: 1.24-1.60, P < 0.01]. Patients with H. pylori-associated atrophic gastritis or intestinal metaplasia were at high risk of CRC (adjusted OR = 3.46, 95%CI: 2.63-4.55, P < 0.01; adjusted OR = 4.86, 95%CI: 3.22-7.34, P < 0.01, respectively). The size and location of the polyps, the histopathological characteristics and the location of CRC were not related to H. pylori infection. CONCLUSION: Our study demonstrates that the incidence of gastric H. pylori infection and H. pylori-associated atrophic gastritis or intestinal metaplasia elevates the risk of colorectal polyps and CRC.

19.
Nat Microbiol ; 5(5): 675-678, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-32265517

RESUMO

Coronavirus disease 2019 (COVID-19), caused by the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), was first reported in Wuhan, Hubei Province, China in late December 2019. We re-analysed 640 throat swabs collected from patients in Wuhan with influenza-like-illness from 6 October 2019 to 21 January 2020 and found that 9 of the 640 throat swabs were positive for SARS-CoV-2 RNA by quantitative PCR, suggesting community transmission of SARS-CoV2 in Wuhan in early January 2020.


Assuntos
Betacoronavirus/isolamento & purificação , Infecções por Coronavirus/diagnóstico , Pneumonia Viral/diagnóstico , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , China , Infecções por Coronavirus/virologia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Pandemias , Pneumonia Viral/virologia , RNA Viral/isolamento & purificação , Reação em Cadeia da Polimerase em Tempo Real , Estudos Retrospectivos , Reação em Cadeia da Polimerase Via Transcriptase Reversa , Adulto Jovem
20.
FEBS J ; 287(21): 4747-4766, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-32112499

RESUMO

Central presbycusis is caused by degradation of the auditory centre during ageing. Its main characteristics are difficulties in understanding language and localizing sound. Presbycusis is an increasingly critical public health problem, but the underlying molecular mechanism has not been fully elucidated. Ferroptosis is a form of regulated cell death caused by iron- and reactive oxygen species-induced lipid peroxidation. Ferroptosis is related to many pathological processes, but whether it participates in the degeneration of the auditory system remains unclear. To investigate this, we measured iron levels in a simulated ageing model established by the addition of d-galactose (d-gal). We found, for the first time, that iron accumulated within cells and that the ultrastructural features of ferroptosis appeared in the auditory cortex with ageing. These changes were accompanied by upregulation of iron regulatory protein 2 (IRP-2), which led to an increase in transferrin receptor 1 (TfR-1), thus increasing iron entry into cells and potentially leading to ferroptosis. In addition, the malondialdehyde (MDA) content and the occurrence of mitochondrial DNA common deletions (CDs) increased, neuron degeneration appeared, and glutathione (GSH) and superoxide dismutase (SOD) activity decreased. Furthermore, we found that treatment with the iron chelator deferoxamine (DFO) and knockdown of IRP-2 both relieved ferroptosis during the simulated ageing process, thus achieving a partial protective effect to delay ageing. In summary, we describe here the first discovery that age-related iron deposition and ferroptosis may be associated with auditory cortex neurodegeneration. Relieving ferroptosis might thus be a new intervention strategy for age-related hearing loss.

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