Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 24
Filtrar
Mais filtros










Base de dados
Intervalo de ano de publicação
1.
Cell Discov ; 10(1): 47, 2024 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-38704363

RESUMO

Neutrophils are the most abundant immune cells that first respond to insults in circulation. Although associative evidence suggests that differences in neutrophils may be linked to the sex-specific vulnerability of inflammatory diseases, mechanistic links remain elusive. Here, we identified extensive sex-specific heterogeneity in neutrophil composition under normal and auto-inflammatory conditions at single-cell resolution. Using a combination of single-cell RNA sequencing analysis, neutrophil-specific genetic knockouts and transfer experiments, we discovered dysregulation of two unconventional (interferon-α responsive and T cell regulatory) neutrophil subsets leading to male-biased incidence, severity and poor prognosis of auto-inflammatory Behçet's uveitis. Genome-wide association study (GWAS) and exosome study revealed that male-specific negative effects of both genetic factors and circulating exosomes on unconventional neutrophil subsets contributed to male-specific vulnerability to disease. Collectively, our findings identify sex-specifically distinct neutrophil subsets and highlight unconventional neutrophil subsets as sex-specific therapeutic targets to limit inflammatory diseases.

2.
Hortic Res ; 11(3): uhae022, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38469381

RESUMO

Mentha is a commonly used spice worldwide, which possesses medicinal properties and fragrance. These characteristics are conferred, at least partially, by essential oils such as menthol. In this study, a gap-free assembly with a genome size of 414.3 Mb and 31,251 coding genes was obtained for Mentha suaveolens 'Variegata'. Based on its high heterozygosity (1.5%), two complete haplotypic assemblies were resolved, with genome sizes of 401.9 and 405.7 Mb, respectively. The telomeres and centromeres of each haplotype were almost fully annotated. In addition, we detected a total of 41,135 structural variations. Enrichment analysis demonstrated that genes involved in terpenoid biosynthesis were affected by these structural variations. Analysis of volatile metabolites showed that M. suaveolens mainly produces piperitenone oxide rather than menthol. We identified three genes in the M. suaveolens genome which encode isopiperitenone reductase (ISPR), a key rate-limiting enzyme in menthol biosynthesis. However, the transcription levels of ISPR were low. Given that other terpenoid biosynthesis genes were expressed, M. suaveolens ISPRs may account for the accumulation of piperitenone oxide in this species. The findings of this study may provide a valuable resource for improving the detection rate and accuracy of genetic variants, thereby enhancing our understanding of their impact on gene function and expression. Moreover, our haplotype-resolved gap-free genome assembly offers novel insights into molecular marker-assisted breeding of Mentha.

3.
Eye (Lond) ; 38(7): 1355-1361, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38160215

RESUMO

OBJECTIVES: To identify the clinical features and outcomes of early vitrectomy in patients with open globe injury (OGI) and the prognostic factors for visual outcome. METHODS: This retrospective observational case series included 390 eyes in 389 patients diagnosed with OGI receiving vitrectomy within four days after injury. Preoperative parameters included the injury types, wound locations, consequent tissue damages, initial visual acuity (VA), and ocular trauma score. Postoperative outcome measures included surgical procedures, retinal (re)attachment, complications, and final VA. The logistic analysis evaluated the prognostic factors for visual outcome. RESULTS: Intraocular foreign bodies (59.2%) and penetrating injuries (28.7%) were the most common injury types. Among the 165 eyes with retinal detachment (RD), 121 (73.3%) had retinal reattachment during early primary vitrectomy, and 32 (19.4%) were repaired during a second or subsequent surgery. Thirteen eyes (3.3%) were enucleated. The final VA improved from the initial level in 207 eyes (55.2%), remained unchanged in 123 (32.8%), and decreased in 45 (12.0%). Multivariable regression revealed that the injury zone, initial VA, RD, and endophthalmitis were associated with poor visual outcomes (P < 0.05). CONCLUSIONS: Higher zone injury, low initial VA, RD, and endophthalmitis are predictors of poor visual outcome in eyes undergoing early vitrectomy for OGI.


Assuntos
Ferimentos Oculares Penetrantes , Acuidade Visual , Vitrectomia , Humanos , Vitrectomia/métodos , Estudos Retrospectivos , Acuidade Visual/fisiologia , Masculino , Feminino , Ferimentos Oculares Penetrantes/cirurgia , Ferimentos Oculares Penetrantes/fisiopatologia , Ferimentos Oculares Penetrantes/diagnóstico , Adulto , Pessoa de Meia-Idade , Prognóstico , Adolescente , Adulto Jovem , Criança , Idoso , Corpos Estranhos no Olho/cirurgia , Corpos Estranhos no Olho/fisiopatologia , Corpos Estranhos no Olho/diagnóstico , Descolamento Retiniano/cirurgia , Descolamento Retiniano/fisiopatologia , Pré-Escolar , Lactente
4.
Afr Health Sci ; 23(3): 328-335, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38357106

RESUMO

Objective: To assess the influence of feedforward control-based health education intervention on the compliance, visual function and self-perceived burden (SPB) among patients with diabetic retinopathy (DR). Methods: Eighty-six DR patients were divided into feedforward control and control groups (n=43). The control group was given routine nursing intervention, based on which the feedforward control group received feedforward control-based health education intervention. The health behavior indices were compared after intervention. The correlations of QOL score with SPB score and health behavior indices were analysed using Pearson's and Spearman's coefficients. Results: After intervention, the total QOL score and scores of symptoms and visual function, physical function, social activity, and mentality and psychology were significantly improved compared with those before intervention, which were significantly higher in the feedforward control group (P<0.05). SPB score was significantly lower in the two groups after intervention than that before intervention, particularly in the feedforward control group (P<0.05). The QOL score of DR patients was significantly negatively correlated with SPB score but positively correlated with health behavior indices (P<0.05). Conclusion: The feedforward control-based health education intervention mode is beneficial for guiding DR patients to promote visual function recovery and to reduce SPB.


Assuntos
Diabetes Mellitus , Retinopatia Diabética , Humanos , Qualidade de Vida , Educação em Saúde , Cooperação do Paciente
5.
J Invertebr Pathol ; 182: 107584, 2021 06.
Artigo em Inglês | MEDLINE | ID: mdl-33811849

RESUMO

In September 2018, a serious disease causing high mortality with red spot syndrome occurred in a Macrobrachium nipponense aquaculture farm in Jintan County, Jiangsu Province, China. In this study, a pathogenic isolate 5-S3 was isolated from diseased M. nipponense and was identified as Aeromonas hydrophila by phenotypically and molecularly. The pathogenicity of the isolate 5-S3 to M. nipponense was determined by challenge experiments. Results of artificial challenge showed A. hydrophila was pathogenic to M. nipponense, the LD50 was 9.58 × 104 CFU/mL, and histopathological analysis revealed that the hepatopancreas of infected M. nipponense exhibited obvious inflammatory responses to A. hydrophila infection. The isolate showed significant phenotypical activities such as the lecithinase, esterase, caseinase and hemolysin which are indicative of their virulence potential. Besides, virulence genes such as aerA, act, fla, ahpß, alt, lip, eprCAI, hlyA, acg and gcaT were detected in the isolate 5-S3. Subsequently, the immune-related genes expression in M. nipponense were evaluated by quantitative real-time PCR (qRT-PCR), and the results showed that the expression levels of dorsal, relish, crustin1, crustin2, anti-lipopolysaccharide factors 1 (ALF1), anti-lipopolysaccharide factors 2 (ALF2), hemocyanin, i-lysozyme and prophenoloxidase were significantly up-regulated in hepatopancreas of M. nipponense after A. hydrophila infection, the stat, p38, crustin3, anti-lipopolysaccharide factors 3 (ALF3) genes had no significant change during the infection. The present results reveal that A. hydrophila was an etiological agent causing red spot syndrome and mass mortality of M. nipponense and the influence of A. hydrophila infection on host immune genes.


Assuntos
Aeromonas hydrophila/fisiologia , Interações Hospedeiro-Patógeno , Imunidade Inata/genética , Palaemonidae/microbiologia , Transcriptoma/imunologia , Animais
6.
Artigo em Inglês | MEDLINE | ID: mdl-33862233

RESUMO

Deltamethrin (Del), a commonly used broad-spectrum insecticide, has been reported to have a toxic effect on aquatic animals, but knowledge in freshwater prawns is limited. This study revealed that Del is highly toxic to Macrobrachium nipponens with the 24 h, 48 h, 72 h, and 96 h LC50 values to be 0.268, 0.165, 0.104, and 0.066 µg/L, respectively. To further investigate the toxic effect of Del in M. nipponense and the reversibility of damage, prawns were exposed to 0.05 µg/L Del for four days and then transferred into fresh water for seven days. Histopathological examination, oxidative stress, hepatopancreas function, respiration system, and immune system were analyzed through multiple biomarkers. Results showed that Del exposure caused severe histopathological damage to hepatopancreas and gill in M. nipponense, and the prominent decrease of acid phosphatase (ACP) and alkaline phosphatase (AKP) activity further enhanced the hepatopancreas damage; the accumulation of malonaldehyde (MDA) and hydrogen peroxide (H2O2), and the decrease of superoxide dismutase (SOD) and glutathione peroxidase (GSH-Px) activity, indicated severe oxidative stress caused by Del. Besides, Del exposure also induced remarkably increased lactic acid (LD) level, decreased lactate dehydrogenase (LDH) activity, and decreased expression of immune-related genes, which demonstrated the respiration disruption and immunosuppression caused by Del. After 7-day decontamination in freshwater, the indicator of hepatopancreas function (ACP and AKP activity) and respiration (LD level and LDH activity) improved to the control group level. However, the histopathological damage and the biomarker in oxidative stress and immune system did not recover to the initial level.


Assuntos
Inseticidas/toxicidade , Nitrilas/toxicidade , Estresse Oxidativo/efeitos dos fármacos , Palaemonidae/efeitos dos fármacos , Piretrinas/toxicidade , Animais , Brânquias/efeitos dos fármacos , Brânquias/patologia , Hepatopâncreas/efeitos dos fármacos , Hepatopâncreas/patologia , Palaemonidae/imunologia , Poluentes Químicos da Água/toxicidade
7.
Eur J Med Chem ; 184: 111767, 2019 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-31622854

RESUMO

Transcriptional enhancer associated domain family members (TEADs) are the most important downstream effectors that play the pivotal role in the development, regeneration and tissue homeostasis. Recent biochemical studies have demonstrated that TEADs could undergo autopalmitoylation that is indispensable for its function making the lipid-binding pocket an attractive target for chemical intervention. Herein, through structure-based virtual screen and rational medicinal chemistry optimization, we identified DC-TEADin02 as the most potent, selective, covalent TEAD autopalmitoylation inhibitor with the IC50 value of 197 ±â€¯19 nM while it showed minimal effect on TEAD-YAP interaction. Further biochemical counter-screens demonstrate the specific thiol reactivity and selectivity of DC-TEADin02 over the kinase family, lipid-binding proteins and epigenetic targets. Notably, DC-TEADin02 inhibited TEADs transcription activity leading to downregulation of YAP-related downstream gene expression. Taken together, our findings proved the validity of modulating transcriptional output in the Hippo signaling pathway through irreversible chemical interventions of TEADs autopalmitoylation activity, which may serve as a qualified chemical tool for TEADs palmitoylation-related studies in the future.


Assuntos
Descoberta de Drogas , Ácido Palmítico/antagonistas & inibidores , Sulfonamidas/farmacologia , Fatores de Transcrição/antagonistas & inibidores , Compostos de Vinila/farmacologia , Relação Dose-Resposta a Droga , Células HCT116 , Células HEK293 , Humanos , Estrutura Molecular , Ácido Palmítico/metabolismo , Relação Estrutura-Atividade , Sulfonamidas/síntese química , Sulfonamidas/química , Fatores de Transcrição/metabolismo , Compostos de Vinila/síntese química , Compostos de Vinila/química
8.
Virulence ; 9(1): 1509-1520, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30221577

RESUMO

Streptococcus suis is a major porcine bacterial pathogen and emerging zoonotic agent. S. suis 5'-nucleotidase is able to convert adenosine monophosphate to adenosine, resulting in inhibiting neutrophil functions in vitro and it is an important virulence factor. Here, we show that S. suis 5'-nucleotidase not only enables producing 2'-deoxyadenosine from 2'-deoxyadenosine monophosphate by the enzymatic assay and reversed-phase high performance liquid chromatography (RP-HPLC) analysis in vitro, but also synthesizes both 2'-deoxyadenosine and adenosine in mouse blood in vivo by RP-HPLC and liquid chromatography with tandem mass spectrometry analyses. Cellular cytotoxicity assay and Western blot analysis indicated that the production of 2'-deoxyadenosine by 5'-nucleotidase triggered the death of mouse macrophages RAW 264.7 in a caspase-3-dependent way. The in vivo infection experiment showed that 2'-deoxyadenosine synthesized by 5'-nucleotidase caused monocytopenia in mouse blood. The in vivo transcriptome analysis in mouse blood showed the inhibitory effect of 5'-nucleotidase on neutrophil functions and immune responses probably mediated through the generation of adenosine. Taken together, these findings indicate that S. suis synthesizes 2'-deoxyadenosine and adenosine by 5'-nucleotidase to dampen host immune responses, which represents a new mechanism of S. suis pathogenesis.


Assuntos
5'-Nucleotidase/metabolismo , Adenosina/biossíntese , Desoxiadenosinas/biossíntese , Interações Hospedeiro-Patógeno/imunologia , Infecções Estreptocócicas/imunologia , Streptococcus suis/enzimologia , Streptococcus suis/patogenicidade , Animais , Proteínas de Bactérias/metabolismo , Feminino , Perfilação da Expressão Gênica , Macrófagos/microbiologia , Macrófagos/patologia , Camundongos , Neutrófilos/microbiologia , Células RAW 264.7 , Fatores de Virulência
9.
J Stroke Cerebrovasc Dis ; 27(9): 2336-2347, 2018 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-29773352

RESUMO

BACKGROUND: Ischemic stroke (IS) is considered to be a heterogeneous, multifactorial disease with a strong genetic background. This study aims to determine whether variants in the antisense noncoding RNA in the INK4 locus (ANRIL) gene are associated with IS in Han Chinese, as well as whether there is evidence of a gene-environment interactions. MATERIALS AND METHODS: A case-controlled association study was conducted in which only patients with atherothrombotic stroke (ATS) were enrolled. Multifactor dimensionality reduction model was employed to screen the best interaction combinations among gene and environmental risk factors; RESULTS: A total of 405 subjects (200 cases and 205 controls) and 16 single nucleotide polymorphisms (SNPs) in ANRIL gene were included in this study. The 4 SNPs (rs1537378, rs2184061, rs7044859, and rs7865618) were found to be significantly related to ATS in Chinese Han nationality. In overall people or subjects aged 45 years or older, the GG genotype and G allele of rs1537378, the AA genotype and A allele of rs2184061 and rs7865618, and the AA genotype of rs7044859 increased the risk of ATS. In males, the GG genotype and G allele of rs1537378, the AA genotype and A allele of rs7865618, and the A allele of rs2184061 conferred a susceptibility to ATS. Additionally, the AAAGAGCAAAAAATAG haplotype exhibited an elevated risk of ATS, and a significant interaction was found in ATS susceptibility between ANRIL gene and dyslipidemia; CONCLUSIONS: The ANRIL gene was related to ATS susceptibility in a Han Chinese. Future studies should be performed with larger samples and among different ethnic populations.


Assuntos
Interação Gene-Ambiente , Trombose Intracraniana/genética , Polimorfismo de Nucleotídeo Único , RNA Longo não Codificante/genética , Acidente Vascular Cerebral/genética , Idoso , Povo Asiático/genética , Estudos de Casos e Controles , China/epidemiologia , Dislipidemias/etnologia , Dislipidemias/genética , Feminino , Frequência do Gene , Estudos de Associação Genética , Predisposição Genética para Doença , Haplótipos , Heterozigoto , Homozigoto , Humanos , Trombose Intracraniana/diagnóstico , Trombose Intracraniana/etnologia , Masculino , Pessoa de Meia-Idade , Fenótipo , Fatores de Risco , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/etnologia
10.
J Ophthalmol ; 2018: 2519375, 2018.
Artigo em Inglês | MEDLINE | ID: mdl-30622818

RESUMO

PURPOSE: To investigate the relationship between transient pupillary light reflex (PLR) and visual function in patients with retinitis pigmentosa (RP). METHODS: A retrospective study was performed with 137 eyes of 73 patients with RP. Transient pupillary light reflex was measured by the vision monitor system (MonColor; Metrovision, France). Dark-adapted transient PLRs were elicited by four specific levels of stimulus luminance (-5, -3, -1, and 0 log cd/m2, blue or white light). Best-corrected visual acuity (BCVA) was recorded based on Early Treatment Diabetic Retinopathy Study (ETDRS) acuity charts. Fixation stability and retinal sensitivity of radial 10° areas were measured with microperimetry. The retinal sensitivity (RS) was divided into central RS (fovea and radial 1° areas) and peripheral RS (radial 3° and 5° areas from the fovea). The patients were further classified into 2 groups (P1 > 75% and P1 < 75%) according to fixation stability. Spearman's correlation was performed to identify significant associations between BCVA, fixation stability, RS, and PLR. RESULTS: Under the stimuli of the same color light, relative pupillary constriction (RPC), latency, or velocity of constriction in the same patients was statistically different in multiple luminance, respectively. Under the same luminance, blue light induced greater RPC and velocity (except for -3 log cd/m2) than white light. Most patients showed varying degrees of threshold elevation and visual function deficiency. Besides, there was a statistically significant difference in the distribution of BCVA, MRS, or fixation stability under different thresholds. The correlation between pupillary constrictive area (PCA) and retinal sensitivity was mainly determined by the peripheral region. Moreover, patients with stable fixation showed a greater correlation between PCA and RS. CONCLUSION: PLR induced by specific colors and luminance may serve as a promising clinical approach for assessing and monitoring rod function in advanced RP patients.

11.
Vet Microbiol ; 205: 26-33, 2017 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-28622857

RESUMO

Streptococcus suis (SS), an important pathogen for pigs, is not only considered as a zoonotic agent for humans, but is also recognized as a major reservoir of antimicrobial resistance contributing to the spread of resistance genes to other pathogenic Streptococcus species. In addition to serotype 2 (SS2), serotype 9 (SS9) is another prevalent serotype isolated from diseased pigs. Although many SS strains have been sequenced, the complete genome of a non-SS2 virulent strain has been unavailable to date. Here, we report the complete genome of GZ0565, a virulent strain of SS9, isolated from a pig with meningitis. Comparative genomic analysis revealed five new putative virulence or antimicrobial resistance-associated genes in strain GZ0565 but not in SS2 virulent strains. These five genes encode a putative triacylglycerol lipase, a TipAS antibiotic-recognition domain protein, a putative TetR family transcriptional repressor, a protein containing a LPXTG domain and a G5 domain, and a type VII secretion system (T7SS) putative substrate (EsxA), respectively. Western blot analysis showed that strain GZ0565 can secrete EsxA. We generated an esxA deletion mutant and showed that EsxA contributes to SS virulence in a mouse infection model. Additionally, the antibiotic resistance gene vanZSS was identified and expression of vanZSS conferred resistance to teicoplanin and dalbavancin in Streptococcus agalactiae. We believe this is the first experimental demonstration of the existence of the T7SS putative substrate EsxA and its contribution to bacterial virulence in SS. Together, our results contribute to further understanding of the virulence and antimicrobial resistance characteristics of SS.


Assuntos
Antibacterianos/farmacologia , Infecções Estreptocócicas/veterinária , Streptococcus suis/patogenicidade , Doenças dos Suínos/microbiologia , Teicoplanina/análogos & derivados , Teicoplanina/farmacologia , Sistemas de Secreção Tipo VII/metabolismo , Animais , Modelos Animais de Doenças , Feminino , Genômica , Humanos , Camundongos , Análise de Sequência de DNA/veterinária , Sorogrupo , Infecções Estreptocócicas/microbiologia , Streptococcus suis/efeitos dos fármacos , Streptococcus suis/genética , Streptococcus suis/imunologia , Suínos , Doenças dos Suínos/imunologia , Sistemas de Secreção Tipo VII/genética
12.
Vet Microbiol ; 199: 111-119, 2017 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-28110777

RESUMO

Streptococcus suis (SS) is an important pathogen for pigs, and it is also considered as a zoonotic agent for humans. Meningitis is one of the most common features of the infection caused by SS, but little is known about the mechanisms of SS meningitis. Recent studies have revealed that small RNAs (sRNAs) have emerged as key regulators of the virulence in several bacteria. In the previous study, we reported that SS sRNA rss04 was up-regulated in pig cerebrospinal fluid and contributes to SS virulence in a zebrafish infection model. Here, we show that rss04 facilitates SS invasion of mouse brain and lung in vivo. Label-free quantitation mass spectrometry analysis revealed that rss04 regulates transcriptional regulator CcpA and several virulence factors including LuxS. Transmission electron microscope and Dot-blot analyses indicated that rss04 represses capsular polysaccharide (CPS) production, which in turn facilitates SS adherence and invasion of mouse brain microvascular endothelial cells bEnd.3 in vitro and activates the mRNA expression of TLR2, CCL2, IL-6 and TNF-α in mouse brain in vivo at 12h post-infection. In addition, rss04 positively regulates SS biofilm formation. Survival analysis of infected mice showed that biofilm state in brain contributes to SS virulence by intracranial subarachnoidal route of infection. Together, our data reveal that SS sRNA rss04 contributes to the induction of meningitis by regulating the CPS synthesis and by inducing biofilm formation, thereby increasing the virulence in a mouse infection model. To our knowledge, rss04 represents the first bacterial sRNA that plays definitive roles in bacterial meningitis.


Assuntos
Biofilmes , Interações Hospedeiro-Patógeno , Meningite/microbiologia , RNA Bacteriano/metabolismo , Infecções Estreptocócicas/microbiologia , Streptococcus suis/fisiologia , Animais , Aderência Bacteriana , Cápsulas Bacterianas/genética , Cápsulas Bacterianas/metabolismo , Encéfalo/microbiologia , Modelos Animais de Doenças , Feminino , Regulação da Expressão Gênica , Pulmão/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Infecções Estreptocócicas/mortalidade , Infecções Estreptocócicas/patologia , Streptococcus suis/genética , Streptococcus suis/patogenicidade , Fatores de Virulência/genética , Fatores de Virulência/metabolismo
13.
Curr Microbiol ; 74(1): 90-96, 2017 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-27847975

RESUMO

Streptococcus suis is a major pathogen of pigs and also an important zoonotic agent for humans. A S. suis protein containing Mac-1 domain (designated Mac) is a protective antigen, exclusively cleaves porcine IgM, and contributes to complement evasion with the presence of high titers of specific porcine anti-S. suis IgM, but its role in S. suis virulence has not been investigated in natural healthy host without specific IgM. In this study, a mac deletion mutant was constructed by homologous recombination in S. suis serotype 2 virulent reference strain P1/7. Deletion of mac did not significantly influence phagocytosis or intracellular survival within murine macrophages RAW264.7, or the oxidative-burst induction of RAW264.7 and murine neutrophils. Furthermore, the mutant is as virulent as the wild-type strain in pig, mouse, and zebrafish infection models. Our data suggest that Mac is not essential for S. suis virulence in strain P1/7 in natural healthy host without specific IgM, and the immunogenicity of Mac does not appear to correlate with its significance for virulence.


Assuntos
Proteínas de Bactérias/metabolismo , Infecções Estreptocócicas/veterinária , Streptococcus suis/patogenicidade , Doenças dos Suínos/microbiologia , Fatores de Virulência/metabolismo , Animais , Proteínas de Bactérias/genética , Feminino , Imunoglobulina M/imunologia , Macrófagos/imunologia , Macrófagos/microbiologia , Camundongos , Camundongos Endogâmicos BALB C , Fagocitose , Células RAW 264.7 , Infecções Estreptocócicas/imunologia , Infecções Estreptocócicas/microbiologia , Streptococcus suis/genética , Streptococcus suis/metabolismo , Suínos , Doenças dos Suínos/imunologia , Virulência , Fatores de Virulência/genética , Peixe-Zebra
14.
Vet Microbiol ; 187: 64-69, 2016 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-27066710

RESUMO

Streptococcus suis (SS) is a major swine pathogen, as well as a zoonotic agent for humans. Numerous factors contribute to SS virulence, but the pathogenesis of SS infection is poorly understood. Here, we show that a novel SS surface protein containing a LysM at the N-terminus (SS9-LysM) contributes to SS virulence. Homology analysis revealed that the amino acid sequence of SS9-LysM from the SS strain GZ0565 shares 99.8-68.7% identity with homologous proteins from other SS strains and 41.2% identity with Group B Streptococcal protective antigen Sip. Immunization experiments showed that 7 out of 30 mice immunized with recombinant SS9-LysM were protected against challenge with the virulent GZ0565 strain, while all of the control mice died within 48h following bacterial challenge. In mouse infection model, the virulence of the SS9-LysM deletion mutant (ΔSS9-LysM) was reduced compared with the wild-type (WT) strain GZ0565 and SS9-LysM complemented strain. In addition, ΔSS9-LysM was significantly more sensitive to killing by pig blood ex vivo and mouse blood in vivo compared with the WT strain and SS9-LysM complemented strain. In vivo transcriptome analysis in mouse blood showed that the WT strain reduced the expression of host genes related to iron-binding by SS9-LysM. Moreover, the total free iron concentration in blood from infected mice was significantly lower for the ΔSS9-LysM strain compared with the WT strain. Together, our data reveal that SS9-LysM facilitates SS survival within blood by releasing more free iron from the host. This represents a new mechanism of SS pathogenesis.


Assuntos
Interações Hospedeiro-Patógeno/fisiologia , Proteínas de Membrana/metabolismo , Streptococcus suis/genética , Streptococcus suis/patogenicidade , Virulência/genética , Sequência de Aminoácidos , Vacinas Bacterianas/imunologia , Sangue/microbiologia , Ferro/metabolismo , Proteínas de Membrana/química , Viabilidade Microbiana/genética , Proteínas Recombinantes/imunologia , Homologia de Sequência de Aminoácidos , Transcriptoma
15.
Angew Chem Int Ed Engl ; 54(41): 12121-6, 2015 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-26306429

RESUMO

An unprecedented rhodium(III)-catalyzed regioselective redox-neutral annulation reaction of 1-naphthylamine N-oxides with diazo compounds was developed to afford various biologically important 1H-benzo[g]indolines. This coupling reaction proceeds under mild reaction conditions and does not require external oxidants. The only by-products are dinitrogen and water. More significantly, this reaction represents the first example of dual functiaonalization of unactivated a primary C(sp(3) )H bond and C(sp(2) )H bond with diazocarbonyl compounds. DFT calculations revealed that an intermediate iminium is most likely involved in the catalytic cycle. Moreover, a rhodium(III)-catalyzed coupling of readily available tertiary aniline N-oxides with α-diazomalonates was also developed under external oxidant-free conditions to access various aminomandelic acid derivatives by an O-atom-transfer reaction.


Assuntos
1-Naftilamina/química , Compostos Azo/química , Hidrogênio/química , Indóis/síntese química , Óxidos de Nitrogênio/química , Ródio/química , Aminação , Compostos de Anilina/química , Catálise , Indóis/química , Malonatos/química , Ácidos Mandélicos/síntese química , Ácidos Mandélicos/química , Modelos Moleculares , Oxirredução
16.
J Org Chem ; 80(12): 6238-49, 2015 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-25989195

RESUMO

We report herein a new strategy for the Rh(III)-catalyzed redox-neutral C7-selective C-H activation/annulation of indolines to rapidly access various privileged 1,7-fused indolines by utilizing an oxidizing-directing group. For example, a Rh(III)-catalyzed redox-neutral C7-selective C-H functionalization of indolines with arylalkynes is described to directly access 7-membered 1,7-fused indolines. Moreover, an unprecedented intramolecular addition of an alkenyl-Cp*Rh(III) species to a carbamoyl moiety occurred to give 1H-pyrroloquinolinones when employing alkyl alkynes. Additionally, an efficient Rh(III)-catalyzed redox-neutral C7-selective C-H activation/alkenylation/aza-Michael addition of indolines is also developed to give 6-membered 1,7-fused indolines. The advantages of these processes are as follows: (1) mild and simple reaction conditions; (2) no need for an external oxidant; (3) broad scope of substrates; and (4) valuable six- or seven-membered 1,7-fused indolines as products.


Assuntos
Indóis/síntese química , Oxidantes/química , Ródio/química , Alcenos/química , Alcinos/química , Catálise , Ciclização , Ligação de Hidrogênio , Indóis/química , Estrutura Molecular , Oxirredução
17.
Chem Commun (Camb) ; 51(37): 7871-4, 2015 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-25854596

RESUMO

A Rh(III)- or Ir(III)-catalyzed direct aldehyde C-H alkynylation was developed for the first time as a simple and practical method for the synthesis of ynones. This catalytic reaction proceeds under mild reaction conditions and tolerates a variety of synthetically important functional groups (e.g., chloro, bromo, aldehyde), thus providing a good complement to previous methods.


Assuntos
Aldeídos/síntese química , Alcinos/síntese química , Carbono/química , Quelantes/química , Hidrogênio/química , Irídio/química , Compostos Organometálicos/química , Ródio/química , Aldeídos/química , Alcinos/química , Catálise , Estrutura Molecular
18.
Bioorg Med Chem Lett ; 24(24): 5671-5674, 2014 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-25467158

RESUMO

A series of B-ring modified analogues of triptolide were synthesized and tested for their cytotoxicity against two human tumor cell lines (U251 and PC-3). From the current investigation, the structure-cytotoxic activity relationships of these analogues suggested that the introduction of hydroxyl, epoxide, halogen or olefinic groups on C5 and/or C6 could still retain the cytotoxicity, albeit a little less potency, and the C7,C8-ß-epoxide group of triptolide was essential to its potent cytotoxic activity.


Assuntos
Antineoplásicos/síntese química , Antineoplásicos/farmacologia , Proliferação de Células/efeitos dos fármacos , Diterpenos/química , Glioma/tratamento farmacológico , Fenantrenos/química , Neoplasias da Próstata/tratamento farmacológico , Diterpenos/farmacologia , Ensaios de Seleção de Medicamentos Antitumorais , Compostos de Epóxi/química , Compostos de Epóxi/farmacologia , Humanos , Masculino , Modelos Moleculares , Estrutura Molecular , Compostos Orgânicos , Fenantrenos/farmacologia , Relação Estrutura-Atividade , Células Tumorais Cultivadas
19.
J Org Chem ; 79(21): 10110-22, 2014 Nov 07.
Artigo em Inglês | MEDLINE | ID: mdl-25296383

RESUMO

A divergent route was developed for the formal total synthesis of triptolide, triptonide, and tripdiolide, as well as a total synthesis of 16-hydroxytriptolide and their analogues in an enantioselective form. Common advanced intermediate 5 was concisely assembled by employing an indium(III)-catalyzed cationic polycyclization reaction and a palladium-catalyzed carbonylation-lactone formation reaction as key steps. This advanced intermediate was readily converted to the above natural products by using palladium-catalyzed cross-coupling or the Claisen rearrangement reaction as key steps. Additionally, preliminary structure-cytotoxic activity relationship studies of C13 suggested that it might be a new modification site that could still retain the cytotoxicity.


Assuntos
Diterpenos/síntese química , Lactonas/química , Fenantrenos/síntese química , Triterpenos/síntese química , Catálise , Diterpenos/química , Compostos de Epóxi/síntese química , Compostos de Epóxi/química , Índio/química , Paládio/química , Fenantrenos/química , Triterpenos/química
20.
Org Lett ; 16(15): 3900-3, 2014 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-25054410

RESUMO

A Rh(III)-catalyzed intramolecular redox-neutral or oxidative annulation of a tethered alkyne has been developed to efficiently construct 3,4-fused indoles via a C-H activation pathway. The advantages of this process are (1) ready availability of annulation precursors; (2) broad substrate scope; (3) complete regioselectivity; (4) simple and mild reaction conditions; and (5) no need for an external oxidant or to employ molecular oxygen as the stoichiometric terminal oxidant.


Assuntos
Alcinos/química , Indóis/síntese química , Ródio/química , Catálise , Ciclização , Indóis/química , Oxirredução
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...