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1.
Acta Haematol ; 2024 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-38228103

RESUMEN

INTRODUCTION Liver dysfunction is common in patients with hemophagocytic lymphohistiocytosis (HLH). However, whether the severity of liver injury is associated with the prognosis of patients with HLH remains to be determined. This study aims to assess the association of the severity of liver involvement with short-term prognosis among adult patients with HLH. METHODS A retrospective study was performed from January 2012 to December 2020, including 150 patients with newly diagnosed HLH and liver injury. RESULTS The majority of our cohort suffered from mild to moderate hepatic damage, presenting with Child-Turcotte-Pugh (CTP) class A (55, 36.7%) or B (74, 49.3%). The prevalence of acute liver failure (ALF) was 9.3% in our cohort. The overall 30-day mortality rate was 49.3% among the study population. HLH patients with ALF showed an extremely adverse prognosis, with a mortality rate as high as 92.9%. In a multivariate analysis, age ≥ 60 years (p = 0.016), BUN ≥ 7 µmol/L (p < 0.001) and malignancy-associated HLH (p < 0.001) at the diagnosis of HLH were identified as being strongly correlated with 30-day prognosis. An excellent predictive power was found. Among the predictive scores used to assess early death of HLH patients with liver injury, the prognostic efficiency of chronic liver failure-sequential organ failure assessment (CLIF-SOFA) (AUROC: 0.936 ± 0.0211) and SOFA score (0.901 ± 0.026) were significantly better than those of the APACHE II (p < 0.001), Model for end-stage liver disease score (p < 0.001) and CTP scores (p < 0.001). The CLIF-SOFA score was slightly better than the SOFA score (p = 0.068). CONCLUSION Patients with old age, elevated BUN and malignancy had inferior survival. CLIF-SOFA and SOFA enables a more accurate prediction of early death in HLH patients with liver injury than other liver-specific and general prognostic models.

2.
Angew Chem Int Ed Engl ; 63(20): e202401324, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38499463

RESUMEN

We report the discovery and biosynthesis of new piperazine alkaloids-arizonamides, and their derived compounds-arizolidines, featuring heterobicyclic and spirocyclic isoquinolone skeletons, respectively. Their biosynthetic pathway involves two crucial non-heme iron enzymes, ParF and ParG, for core skeleton construction. ParF has a dual function facilitating 2,3-alkene formation of helvamide, as a substrate for ParG, and oxidative cleavage of piperazine. Notably, ParG exhibits catalytic versatility in multiple oxidative reactions, including cyclization and ring reconstruction. A key amino acid residue Phe67 was characterized to control the formation of the constrained arizonamide B backbone by ParG.


Asunto(s)
Alcaloides , Alcaloides/química , Alcaloides/metabolismo , Alcaloides/biosíntesis , Piperazinas/química , Piperazinas/metabolismo , Hierro/química , Hierro/metabolismo , Ciclización , Biocatálisis , Estructura Molecular , Compuestos de Espiro/química , Compuestos de Espiro/metabolismo , Oxidación-Reducción , Piperazina/química , Piperazina/metabolismo
3.
Glycobiology ; 33(5): 423-431, 2023 06 03.
Artículo en Inglés | MEDLINE | ID: mdl-36988396

RESUMEN

A novel Gal-binding lectin from mussels (Crenomytilus grayanus, CGL) with 6 binding sites in the dimeric structure has been previously shown to have antifungal, anticancer, and antibacterial activities. In this study, a glycan array was used to confirm that CGL recognizes a range of non-reducing end α- or ß-linked Gal glycans on normal cells but not sialic acid-capped glycans. This finding suggests that CGL has potential in the tumor detection due to the hyper-sialylation present in cell surface glycans from cancer cells. To evaluate the feasibility of this possibility, we labeled CGL with biotin and then mixed it with streptavidin-horseradish peroxidase (HRP) to create a CGL-biotin-SP complex as a probe for use in enzyme-linked lectin assays. CGL-biotin-SP successfully distinguished not only HeLa cells and de-sialylated HeLa cells that mimic normal cell surface glycans but also lung and breast cancer cells with different metastatic abilities. This work provides the insights into a new Gal-binding lectin by establishing its specificity and also demonstrates practical applications in cancer diagnosis greater than other reported lectins.


Asunto(s)
Lectinas , Mytilidae , Animales , Humanos , Lectinas/química , Células HeLa , Biotina , Mytilidae/metabolismo , Polisacáridos/metabolismo
4.
Appl Microbiol Biotechnol ; 107(23): 7089-7104, 2023 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-37733049

RESUMEN

Nitriles are of significant interest in the flavor and fragrance industries with potential application in cosmetics due to their higher stability than analogous aldehydes. However, the traditional methods to prepare nitriles need toxic reagents and hash conditions. This work aimed to develop a chemoenzymatic strategy to synthesize nitriles from natural aldehydes with aldoxime as the intermediate. A non-classical aldoxime dehydratase (Oxd) was discovered from the fungus Aspergillus ibericus (OxdAsp) to catalyze the dehydration of aldoximes to corresponding nitriles under mild conditions. The amino acid sequence of OxdAsp exhibits an approximately 20% identity with bacterial Oxds. OxdAsp contains a heme prosthetic group bound with the axial H287 in the catalytic pocket. The structure models of OxdAsp with substrates suggest that its catalytic triad is Y138-R141-E192, which is different from the classically bacterial Oxds of His-Arg-Ser/Thr. The catalytic mechanism of OxdAsp was proposed based on the mutagenesis of key residues. The hydroxyl group of the substrate is fixed by E192 to increase its basicity. Y138 acts as a general acid-based catalyst, and its phenolic proton is polarized by the adjacent R141. The protonated Y138 would donate a proton to the hydroxyl group of the substrate and eliminate a water molecule from aldoxime to produce nitrile. The recombinant OxdAsp can efficiently dehydrate citronellal oxime and cinnamaldoxime to citronellyl nitrile and cinnamonitrile in aqueous media, which are applied as fragrance ingredients in the food and cosmetic fields. KEY POINTS: • A novel aldoxime dehydratase from the Aspergillus genus was first characterized as a heme-binding protein. • The catalytic mechanism was predicted based on the molecular interactions of the catalytic pocket with the substrate. • A chemoenzymatic strategy was developed to synthesize nitriles from natural aldehydes with aldoxime as the intermediate.


Asunto(s)
Bacterias , Protones , Bacterias/metabolismo , Hidroliasas/metabolismo , Nitrilos/metabolismo , Aldehídos
5.
BMC Plant Biol ; 22(1): 577, 2022 Dec 12.
Artículo en Inglés | MEDLINE | ID: mdl-36503377

RESUMEN

BACKGROUND: Taxus is a rare gymnosperm plant that is the sole producer of the anticancer drug paclitaxel. The growth and development of Taxus is affected by environmental factors such as light. However, little is known about how light conditions affect growth and metabolic processes, especially paclitaxel biosynthesis. RESULTS: In this study, we applied three different light conditions to Taxus chinensis young saplings and investigated the physiological response and gene expression. Our observations showed that exposure to high light led to oxidative stress, caused photoinhibition, and damaged the photosynthetic systems in T. chinensis. The paclitaxel content in T. chinensis leaves was significantly decreased after the light intensity increased. Transcriptomic analysis revealed that numerous genes involved in paclitaxel biosynthesis and phenylpropanoid metabolic pathways were downregulated under high light. We also analyzed the expression of JA signaling genes, bHLH, MYB, AP2/ERF transcription factors, and the CYP450 families that are potentially related to paclitaxel biosynthesis. We found that several CYP450s, MYB and AP2/ERF genes were induced by high light. These genes may play an important role in tolerance to excessive light or heat stress in T. chinensis. CONCLUSIONS: Our study elucidates the molecular mechanism of the effects of light conditions on the growth and development of T. chinensis and paclitaxel biosynthesis, thus facilitating the artificial regeneration of Taxus and enhancing paclitaxel production.


Asunto(s)
Taxus , Taxus/genética , Perfilación de la Expresión Génica , Fotosíntesis/genética , Cycadopsida , Luz , Paclitaxel
6.
J Biomed Sci ; 29(1): 9, 2022 Feb 07.
Artículo en Inglés | MEDLINE | ID: mdl-35130876

RESUMEN

BACKGROUND: K1 capsular polysaccharide (CPS)-associated Klebsiella pneumoniae is the primary cause of pyogenic liver abscesses (PLA) in Asia. Patients with PLA often have serious complications, ultimately leading to a mortality of ~ 5%. This K1 CPS has been reported as a promising target for development of glycoconjugate vaccines against K. pneumoniae infection. The pyruvylation and O-acetylation modifications on the K1 CPS are essential to the immune response induced by the CPS. To date, however, obtaining the fragments of K1 CPS that contain the pyruvylation and O-acetylation for generating glycoconjugate vaccines still remains a challenge. METHODS: We analyzed the digested CPS products with NMR spectroscopy and mass spectrometry to reveal a bacteriophage-derived polysaccharide depolymerase specific to K1 CPS. The biochemical and biophysical properties of the enzyme were characterized and its crystal structures containing bound CPS products were determined. We also performed site-directed mutagenesis, enzyme kinetic analysis, phage absorption and infectivity studies, and treatment of the K. pneumoniae-infected mice with the wild-type and mutant enzymes. RESULTS: We found a bacteriophage-derived polysaccharide lyase that depolymerizes the K1 CPS into fragments of 1-3 repeating trisaccharide units with the retention of the pyruvylation and O-acetylation, and thus the important antigenic determinants of intact K1 CPS. We also determined the 1.46-Å-resolution, product-bound crystal structure of the enzyme, revealing two distinct carbohydrate-binding sites in a trimeric ß-helix architecture, which provide the first direct evidence for a second, non-catalytic, carbohydrate-binding site in bacteriophage-derived polysaccharide depolymerases. We demonstrate the tight interaction between the pyruvate moiety of K1 CPS and the enzyme in this second carbohydrate-binding site to be crucial to CPS depolymerization of the enzyme as well as phage absorption and infectivity. We also demonstrate that the enzyme is capable of protecting mice from K1 K. pneumoniae infection, even against a high challenge dose. CONCLUSIONS: Our results provide insights into how the enzyme recognizes and depolymerizes the K1 CPS, and demonstrate the potential use of the protein not only as a therapeutic agent against K. pneumoniae, but also as a tool to prepare structurally-defined oligosaccharides for the generation of glycoconjugate vaccines against infections caused by this organism.


Asunto(s)
Bacteriófagos , Infecciones por Klebsiella , Liasas , Animales , Cápsulas Bacterianas/genética , Bacteriófagos/genética , Humanos , Cinética , Klebsiella pneumoniae , Ratones
7.
Proteome Sci ; 20(1): 15, 2022 Sep 21.
Artículo en Inglés | MEDLINE | ID: mdl-36131344

RESUMEN

BACKGROUND: Multi-omics technology provides a good tool to analyze the protein toxin composition and search for the potential pathogenic factors of Solenopsis invicta, under the great harm of the accelerated invasion in southern China. METHODS: Species collection, functional annotation, toxin screening, and 3D modeling construction of three interested toxins were performed based on the successfully constructed transcriptome and proteome of S. invicta. RESULTS: A total of 33,231 unigenes and 721 proteins were obtained from the constructed transcriptome and proteome, of which 9,842 (29.62%) and 4,844 (14.58%) unigenes, as well as 469 (65.05%) and 71 (99.45%) proteins were annotated against the databases of Gene Ontology and Kyoto Encyclopedia of Genes and Genomes, respectively. After comparing with the uniprot toxin database, a total of 316 unigenes and 47 proteins (calglandulin, venom allergen 3, and venom prothrombin activator hopsarin-D, etc.) were successfully screened. CONCLUSIONS: The update of annotations at the transcriptome and proteome levels presents a progression in the comprehension of S. invicta in China. We also provide a protein toxin list that could be used for further exploration of toxicity as well as its antagonistic strategy by S. invicta.

8.
Ecotoxicol Environ Saf ; 233: 113315, 2022 Mar 15.
Artículo en Inglés | MEDLINE | ID: mdl-35189521

RESUMEN

BACKGROUND: The application of multi-omics technologies provides a new perspective to solve three main problems including species identification, toxin screening and effective antagonist conformation in the studies of marine toxic jellyfish. METHODS: A series of transcriptome-proteome based analysis accompanied with toxicity evaluations were performed for the ornamental jellyfish Phacellophora camtschatica. RESULTS: Through combined morphological observation and Cytochrome c oxidase subunit Ⅰ (CO1) molecular alignment, the sample jellyfish was identified as P. camtschatica. A total of 25,747 unigenes and 3058 proteins were obtained from the successfully constructed transcriptome and proteome, in which 6869 (26.68%) and 6618 (25.70%) unigenes, as well as 2536 (82.93%) and 2844 (93.00%) proteins were annotated against the databases of Gene ontology (GO) and Kyoto Encyclopedia of Genes and Genomes (KEGG), respectively. The jellyfish displayed obvious in vivo lethal effects with significant increases of multi-organ functional indexes as well as in vitro activities. Total of 62 toxins from 120 toxin-related unigenes were screened including 16 metalloproteases, 11 phospholipases and others. Moreover, 11 toxins were further screened by using the erythrocyte model, where the zinc metalloproteinase nas-15-like (1) was the most abundant. Finally, Diltiazem greatly improved the survival rate while EDTA slightly prolonged the survival time in ICR mice. CONCLUSION: P. camtschatica is a poisonous jellyfish with diversified toxic components, in which metalloproteinase probably plays an important role in toxicities, and excessive Ca2+ entry may be the main mechanism of systemic lethal toxicity.


Asunto(s)
Venenos de Cnidarios , Proteoma , Animales , Venenos de Cnidarios/genética , Venenos de Cnidarios/metabolismo , Venenos de Cnidarios/toxicidad , Ratones , Ratones Endogámicos ICR , Proteoma/genética , Proteómica , Transcriptoma
9.
Int J Mol Sci ; 23(18)2022 Sep 08.
Artículo en Inglés | MEDLINE | ID: mdl-36142298

RESUMEN

The edible fungus Tremella fuciformis was shown to have a high molecular weight (1.87 × 103 kDa) bioactive polysaccharide, denoted as TFP-F1. Monosaccharide composition and NMR analysis of the polysaccharide and its derivatives indicated it contained fucose (Fucp), xylose (Xylp), mannose (Manp), and glucuronic acid (GlcAp) in a ratio of 0.9:1.0:3.2:1.2. Using IR, NMR, and GC-MS spectroscopic data, the structure of TFP-F1 was elucidated as {→3)-[ß-D-GlcAp-(1→2)]-α-D-Manp-(1→3)-α-D-Manp-(1→3)-[α-L-Fucp-(1→2)-ß-D-Xylp-(1→2)]-α-D-Manp-(1→}n, with partial acetylation of C6-OH in mannoses. Furthermore, at a concentration of 1 µg/mL, TFP-F1 was found to stimulate the secretion of TNF-α and IL-6 in J774A.1 macrophage cells in vitro via interaction with toll-like receptor 4 (TLR4). The removal of O-acetyl groups led to the loss of immunomodulatory activities, demonstrating that O-acetyl groups play an essential role in enhancing the production of pro-inflammatory cytokines.


Asunto(s)
Receptor Toll-Like 4 , Factor de Necrosis Tumoral alfa , Acetilación , Basidiomycota , Citocinas , Carbohidratos de la Dieta , Fucosa , Ácido Glucurónico , Inmunomodulación , Interleucina-6 , Manosa , Monosacáridos , Polisacáridos/química , Polisacáridos/farmacología , Xilosa
10.
J Am Chem Soc ; 142(46): 19446-19450, 2020 11 18.
Artículo en Inglés | MEDLINE | ID: mdl-33166120

RESUMEN

Pseudaminic acid (Pse), a unique carbohydrate in surface-associated glycans of pathogenic bacteria, has pivotal roles in virulence. Owing to its significant antigenicity and absence in mammals, Pse is considered an attractive target for vaccination or antibody-based therapies against bacterial infections. However, a specific and universal probe for Pse, which could also be used in immunotherapy, has not been reported. In a prior study, we used a tail spike protein from a bacteriophage (ΦAB6TSP) that digests Pse-containing exopolysaccharide (EPS) from Acinetobacter baumannii strain 54149 (Ab-54149) to form a glycoconjugate for preparing anti-Ab-54149 EPS serum. We report here that a catalytically inactive ΦAB6TSP (I-ΦAB6TSP) retains binding ability toward Pse. In addition, an I-ΦAB6TSP-DyLight-650 conjugate (Dy-I-ΦAB6TSP) was more sensitive in detecting Ab-54149 than an antibody purified from anti- Ab-54149 EPS serum. Dy-I-ΦAB6TSP also cross-reacted with other pathogenic bacteria containing Pse on their surface polysaccharides (e.g., Helicobacter pylori and Enterobacter cloacae), revealing it to be a promising probe for detecting Pse across bacterial species. We also developed a detection method that employs I-ΦAB6TSP immobilized on microtiter plate. These results suggested that the anti-Ab-54149 EPS serum would exhibit cross-reactivity to Pse on other organisms. When this was tested, this serum facilitated complement-mediated killing of H. pylori and E. cloacae, indicating its potential as a cross-species antibacterial agent. This work opens new avenues for diagnosis and treatment of multidrug resistant (MDR) bacterial infections.


Asunto(s)
Antibacterianos/química , Infecciones Bacterianas/terapia , Bacteriófagos/química , Azúcares Ácidos/química , Proteínas de la Cola de los Virus/química , Acinetobacter baumannii/química , Antibacterianos/farmacología , Anticuerpos/química , Farmacorresistencia Bacteriana Múltiple , Enterobacter cloacae/virología , Glicoconjugados/química , Glicósido Hidrolasas , Helicobacter pylori/virología , Polisacáridos/química , Suero/química , Azúcares Ácidos/metabolismo , Azúcares Ácidos/uso terapéutico , Proteínas de la Cola de los Virus/metabolismo
11.
J Org Chem ; 85(9): 6188-6194, 2020 05 01.
Artículo en Inglés | MEDLINE | ID: mdl-32227863

RESUMEN

An ynamide-mediated one-pot, two-step intermolecular esterification via the condensation of carboxylic acids with nucleophilic hydroxyl species was reported. A broad substrate scope with respect to carboxylic acids, alcohols, and phenols was observed. The α-acyloxyenamide intermediates formed by the addition of carboxylic acids to ynamides proved to be effective acylating reagents for the esterification of alcohol and phenol derivatives with the assistance of base catalysis. Notably, the racemization of the α-chiral center of carboxylic acids can be avoided.

12.
Health Qual Life Outcomes ; 18(1): 367, 2020 Nov 13.
Artículo en Inglés | MEDLINE | ID: mdl-33187553

RESUMEN

BACKGROUND: Early prelingual auditory development (EPLAD) is a fundamental and important process in the speech and language development of infants and toddlers. The Infant-Toddler Meaningful Auditory Integration Scale (ITMAIS) is a widely used measurement tool for EPLAD, however it has not yet undergone a comprehensive psychometric analysis. The aim of this research was to modify and verify the psychometric properties of ITMAIS using a combination of Item Response Theory (IRT) and Classical Test Theory (CTT). METHODS: Stage 1-1730 children were retrospectively recruited to enable the application of an IRT model, specifically the graded response model, to modify the ITMAIS. Stage 2-another 450 infants and toddlers with normal hearing or permanent hearing loss before auditory intervention were recruited to verify the psychometric properties of the modified ITMAIS (ITMAIS-m) using the CTT method. RESULTS: Using the metric of the graded response model, by removing item 2 from the ITMAIS, ITMAIS-m demonstrated discrimination parameters ranging from 3.947 to 5.431, difficulty parameters from - 1.146 to 1.150, item information distributed between 4.798 and 9.259 and a test information score of 48.061. None of the items showed differential item functioning. ITMAIS-m was further verified in Stage 2, showing Cronbach's α of 0.919 and item-total correlations ranging from 0.693 to 0.851. There was good convergent validity of ITMAIS-m with other auditory outcome measure (r = 0.932) and pure tone average thresholds (r ranging from - 0.670 to - 0.909), as well as a high ability to discriminate between different hearing grades (Cohen d ranging from 0.41 to 5.83). CONCLUSIONS: The ITMAIS-m is a reliable and valid tool for evaluating EPLAD in infants and toddlers, which can be efficiently and precisely applied in clinical practice. The combined use of IRT and CTT provides a powerful means to modify psychometrically robust scales aimed at childhood auditory outcome measurements.


Asunto(s)
Percepción Auditiva , Audición , Psicometría/métodos , Preescolar , China , Femenino , Pruebas Auditivas , Humanos , Lactante , Desarrollo del Lenguaje , Masculino , Reproducibilidad de los Resultados
13.
Nature ; 513(7516): 59-64, 2014 Sep 04.
Artículo en Inglés | MEDLINE | ID: mdl-25079328

RESUMEN

Liver cirrhosis occurs as a consequence of many chronic liver diseases that are prevalent worldwide. Here we characterize the gut microbiome in liver cirrhosis by comparing 98 patients and 83 healthy control individuals. We build a reference gene set for the cohort containing 2.69 million genes, 36.1% of which are novel. Quantitative metagenomics reveals 75,245 genes that differ in abundance between the patients and healthy individuals (false discovery rate < 0.0001) and can be grouped into 66 clusters representing cognate bacterial species; 28 are enriched in patients and 38 in control individuals. Most (54%) of the patient-enriched, taxonomically assigned species are of buccal origin, suggesting an invasion of the gut from the mouth in liver cirrhosis. Biomarkers specific to liver cirrhosis at gene and function levels are revealed by a comparison with those for type 2 diabetes and inflammatory bowel disease. On the basis of only 15 biomarkers, a highly accurate patient discrimination index is created and validated on an independent cohort. Thus microbiota-targeted biomarkers may be a powerful tool for diagnosis of different diseases.


Asunto(s)
Tracto Gastrointestinal/microbiología , Cirrosis Hepática/diagnóstico , Cirrosis Hepática/microbiología , Metagenómica , Microbiota/genética , Microbiota/fisiología , Estudios de Casos y Controles , Enfermedad Crónica , Diabetes Mellitus Tipo 2/microbiología , Heces/microbiología , Marcadores Genéticos/genética , Salud , Humanos , Enfermedades Inflamatorias del Intestino/microbiología , Boca/microbiología , Filogenia , Reproducibilidad de los Resultados
14.
J Am Chem Soc ; 140(28): 8639-8643, 2018 07 18.
Artículo en Inglés | MEDLINE | ID: mdl-29965749

RESUMEN

Pseudaminic acid (Pse) has been known for participating in crucial bacterial virulence and thus is an attractive target in the development of glycoconjugate vaccine. Particularly, this therapeutic alternative was suggested to be a potential solution against antibiotic resistant Acinetobacter baumannii that poses a serious global health threat. Also, Pse was found to be involved in the exopolysaccharide (EPS) of mild antibiotic resistant A. baumannii strain 54149 ( Ab-54149) of which specific glycosyl linkage can be depolymerized by phage ΦAB6 tailspike protein (ΦAB6TSP). In this study, we found that the antibodies induced by Ab-54149 EPS was capable of recognizing a range of EPS of other clinical A. baumannii strains, and deemed as a great potential material for vaccination. To efficiently acquire homogeneous EPS-derived oligosaccharide with significant immunogenic activity for the production of glycoconjugate, we used the ΦAB6TSP for the fragmentation of Ab-54149 EPS instead of chemical methods. Moreover, insight into the ligand binding characterization of ΦAB6TSP suggested the branched Pse on the Ab-54149 EPS served as a recognition site of ΦAB6TSP. The serum boosted by ΦAB6TSP-digested product and carrier protein CRM197 conjugate complex displayed specific sensitivity toward Ab-54149 EPS with bacterial killing activity. Strikingly, Pse is an ideal epitope with strong antigenicity, profiting the application of the probe for pathogen detection and glyco-based vaccine.


Asunto(s)
Acinetobacter baumannii/inmunología , Vacunas Bacterianas/inmunología , Glicoconjugados/inmunología , Polisacáridos Bacterianos/inmunología , Azúcares Ácidos/inmunología , Vacunas Conjugadas/inmunología , Proteínas de la Cola de los Virus/inmunología , Infecciones por Acinetobacter/inmunología , Infecciones por Acinetobacter/prevención & control , Glicósido Hidrolasas , Humanos , Modelos Moleculares
15.
Angew Chem Int Ed Engl ; 56(20): 5565-5569, 2017 05 08.
Artículo en Inglés | MEDLINE | ID: mdl-28398608

RESUMEN

3D plasmonic colloidosomes are superior SERS sensors owing to their high sensitivity and excellent tolerance to laser misalignment. Herein, we incorporate plasmonic colloidosomes in a microfluidic channel for online SERS detection. Our method resolves the poor signal reproducibility and inter-sample contamination in the existing online SERS platforms. Our flow system offers rapid and continuous online detection of 20 samples in less than 5 min with excellent signal reproducibility. The isolated colloidosomes prevent cross-sample and channel contamination, allowing accurate quantification of samples over a concentration range of five orders of magnitude. Our system demonstrates high-resolution multiplex detection with fully preserved signal and Raman features of individual analytes in a mixture. High-throughput multi-assay analysis is performed, which highlights that our system is capable of rapid identification and quantification of a sequence of samples containing various analytes and concentrations.

16.
Infect Immun ; 83(9): 3396-409, 2015 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-26077758

RESUMEN

Klebsiella pneumoniae (strain 43816, K2 serotype) induces interleukin-1ß (IL-1ß) secretion, but neither the bacterial factor triggering the activation of these inflammasome-dependent responses nor whether they are mediated by NLRP3 or NLRC4 is known. In this study, we identified a capsular polysaccharide (K1-CPS) in K. pneumoniae (NTUH-K2044, K1 serotype), isolated from a primary pyogenic liver abscess (PLA K. pneumoniae), as the Klebsiella factor that induces IL-1ß secretion in an NLRP3-, ASC-, and caspase-1-dependent manner in macrophages. K1-CPS induced NLRP3 inflammasome activation through reactive oxygen species (ROS) generation, mitogen-activated protein kinase phosphorylation, and NF-κB activation. Inhibition of both the mitochondrial membrane permeability transition and mitochondrial ROS generation inhibited K1-CPS-mediated NLRP3 inflammasome activation. Furthermore, IL-1ß secretion in macrophages infected with PLA K. pneumoniae was shown to depend on NLRP3 but also on NLRC4 and TLR4. In macrophages infected with a K1-CPS deficiency mutant, an lipopolysaccharide (LPS) deficiency mutant, or K1-CPS and LPS double mutants, IL-1ß secretion levels were lower than those in cells infected with wild-type PLA K. pneumoniae. Our findings indicate that K1-CPS is one of the Klebsiella factors of PLA K. pneumoniae that induce IL-1ß secretion through the NLRP3 inflammasome.


Asunto(s)
Antígenos Bacterianos/inmunología , Proteínas Portadoras/inmunología , Inflamasomas/inmunología , Infecciones por Klebsiella/inmunología , Klebsiella pneumoniae/inmunología , Polisacáridos Bacterianos/inmunología , Animales , Western Blotting , Línea Celular , Ensayo de Inmunoadsorción Enzimática , Interacciones Huésped-Parásitos/inmunología , Humanos , Interleucina-1beta/inmunología , Ratones , Proteína con Dominio Pirina 3 de la Familia NLR , Reacción en Cadena en Tiempo Real de la Polimerasa
17.
Mol Cell Proteomics ; 12(10): 2701-13, 2013 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-23828892

RESUMEN

Thermus thermophilus HB27 is an extremely thermophilic eubacteria with a high frequency of natural competence. This organism is therefore often used as a thermophilic model to investigate the molecular basis of type IV pili-mediated functions, such as the uptake of free DNA, adhesion, twitching motility, and biofilm formation, in hot environments. In this study, the phosphoproteome of T. thermophilus HB27 was analyzed via a shotgun approach and high-accuracy mass spectrometry. Ninety-three unique phosphopeptides, including 67 in vivo phosphorylated sites on 53 phosphoproteins, were identified. The distribution of Ser/Thr/Tyr phosphorylation sites was 57%/36%/7%. The phosphoproteins were mostly involved in central metabolic pathways and protein/cell envelope biosynthesis. According to this analysis, the ATPase motor PilF, a type IV pili-related component, was first found to be phosphorylated on Thr-368 and Ser-372. Through the point mutation of PilF, mimic phosphorylated mutants T368D and S372E resulted in nonpiliated and nontwitching phenotypes, whereas nonphosphorylated mutants T368V and S372A displayed piliation and twitching motility. In addition, mimic phosphorylated mutants showed elevated biofilm-forming abilities with a higher initial attachment rate, caused by increasing exopolysaccharide production. In summary, the phosphorylation of PilF might regulate the pili and biofilm formation associated with exopolysaccharide production.


Asunto(s)
Biopelículas/crecimiento & desarrollo , Proteínas Fimbrias/fisiología , Fimbrias Bacterianas/fisiología , Fosfoproteínas/fisiología , Thermus thermophilus/fisiología , Biopolímeros/metabolismo , Escherichia coli/genética , Fosfopéptidos/fisiología , Fosforilación , Polisacáridos/metabolismo , Proteómica
18.
BMC Genomics ; 15: 753, 2014 Sep 02.
Artículo en Inglés | MEDLINE | ID: mdl-25179593

RESUMEN

BACKGROUND: Human gut microbiota plays an important role in the pathogenesis of cirrhosis complications. Although the phylogenetic diversity of intestinal microbiota in patients with liver cirrhosis has been examined in several studies, little is known about their functional composition and structure. RESULTS: To characterize the functional gene diversity of the gut microbiome in cirrhotic patients, we recruited a total of 42 individuals, 12 alcoholic cirrhosis patients, 18 hepatitis B virus (HBV)-related cirrhosis patients, and 12 normal controls. We determined the functional structure of these samples using a specific functional gene array, which is a combination of GeoChip for monitoring biogeochemical processes and HuMiChip specifically designed for analyzing human microbiomes. Our experimental data showed that the microbial community functional composition and structure were dramatically distinctive in the alcoholic cirrhosis. Various microbial functional genes involved in organic remediation, stress response, antibiotic resistance, metal resistance, and virulence were highly enriched in the alcoholic cirrhosis group compared to the control group and HBV-related cirrhosis group. Cirrhosis may have distinct influences on metabolic potential of fecal microbial communities. The abundance of functional genes relevant to nutrient metabolism, including amino acid metabolism, lipid metabolism, nucleotide metabolism, and isoprenoid biosynthesis, were significantly decreased in both alcoholic cirrhosis group and HBV-related cirrhosis group. Significant correlations were observed between functional gene abundances and Child-Pugh scores, such as those encoding aspartate-ammonia ligase, transaldolase, adenylosuccinate synthetase and IMP dehydrogenase. CONCLUSIONS: Functional gene array was utilized to study the gut microbiome in alcoholic and HBV-related cirrhosis patients and controls in this study. Our array data indicated that the functional composition of fecal microbiomes was heavily influenced by cirrhosis, especially by alcoholic cirrhosis. This study provides new insights into the functional potentials and activity of gut microbiota in cirrhotic patients with different etiologies.


Asunto(s)
Heces/microbiología , Cirrosis Hepática , Metagenoma , Metagenómica , Microbiota , Adulto , Anciano , Alcoholes/efectos adversos , Biodiversidad , Análisis por Conglomerados , Femenino , Interacción Gen-Ambiente , Variación Genética , Humanos , Cirrosis Hepática/etiología , Masculino , Metagenoma/efectos de los fármacos , Metagenómica/métodos , Persona de Mediana Edad
19.
Helicobacter ; 19(5): 356-66, 2014 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-24834789

RESUMEN

BACKGROUND: The lon gene of Helicobacter pylori strains is constitutively expressed during growth. However, virtually nothing is understood concerning the role of Lon in H. pylori. This study examined the function and physiological role of Lon in H. pylori (HpLon) using a trapping approach to identify putative Lon binding partners in the bacterium. MATERIALS AND METHODS: Protease-deficient Lon was expressed and served as the bait in trapping approach to capture the interacting partners in H. pylori. The antibiotic susceptibility of wild-type and lon derivative mutants was determined by the E test trips and the disc diffusion assay. The effect of HpLon on RdxA activity was detected the change in NADPH oxidation and metronidazole reduction by spectrophotometer. RESULTS: Lon in Helicobacter pylori (HpLon) interacting partners are mostly associated with metronidazole activation. lon mutant presents more susceptible to metronidazole than that of the wild type, and this phenotype is recovered by complementation of the wild-type Lon. We found that the ATPases associated with a variety of cellular activities (AAA(+) ) module of HpLon causes a decrease in both NADPH oxidase and Mtz reductase activity in RdxA, a major Mtz-activating enzyme in H. pylori. CONCLUSION: Metronidazole resistance of H. pylori causes the serious medical problem worldwide. In this study, HpLon is involved in metronidazole susceptibility among H. pylori strains. We provide the evidence that HpLon alters RdxA activity in vitro. The decrease in metronidazole activation caused by HpLon is possibly prior to accumulate mutation in rdxA gene before the metronidazole-resistant strains to be occurred.


Asunto(s)
Antiinfecciosos/farmacología , Proteínas Bacterianas/metabolismo , Helicobacter pylori/enzimología , Metronidazol/farmacología , Nitrorreductasas/metabolismo , Proteasa La/metabolismo , Secuencia de Aminoácidos , Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana , Infecciones por Helicobacter/microbiología , Helicobacter pylori/efectos de los fármacos , Helicobacter pylori/genética , Helicobacter pylori/fisiología , Humanos , Pruebas de Sensibilidad Microbiana , Datos de Secuencia Molecular , Mutación , NADPH Oxidasas/genética , NADPH Oxidasas/metabolismo , Nitrorreductasas/genética , Proteasa La/genética , Alineación de Secuencia
20.
Artículo en Inglés | MEDLINE | ID: mdl-38594973

RESUMEN

Background The paradoxical occurrence of psoriasis triggered by Interleukin-17 (IL-17) inhibitors is notable due to its prominent symptoms and the therapeutic dilemma it presents for follow-up care. Objective To describe cases in our clinic, perform an in-depth literature review, and suggest the most probable mechanisms of action. Method We conducted a literature review on published cases of IL-17 inhibitor-induced psoriasis. Results We found 22 articles reporting 30 cases of IL-17 inhibitor-induced paradoxical psoriasis, primarily observed in patients with a previous psoriasis history. Almost 60% of cases showed a change in lesion morphology, with the plaque or pustular type being prevalent. About 73.3% of patients had to discontinue the implicated drug, leading to partial or complete symptom resolution. The mechanism behind this response seemed to involve IL-17 inhibitors downregulating Tumour Necrosis Factor alpha (TNF-α), subsequently upregulating plasmacytoid dendritic cells and triggering unopposed IFN-alpha (IFN-α) production. Limitation Data are confined to case reports and case series. Conclusion More assertive measures are recommended for treating paradoxical psoriasis induced by IL-17 inhibitors than those caused by TNF-α inhibitors. Reintroducing an IL-17 inhibitor is not advised, as patients did not show improvement.

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