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1.
Medicine (Baltimore) ; 103(17): e37876, 2024 Apr 26.
Artículo en Inglés | MEDLINE | ID: mdl-38669435

RESUMEN

OBJECTIVE: Exoskeletons can play a crucial role in post-TKA rehabilitation by accelerating recovery, improving mobility, and reducing further injury risk. This meta-analysis evaluated the effectiveness of exoskeletons in post-total knee replacement (TKR) rehabilitation. DESIGN: Comprehensive searches were conducted on PubMed, OVID Medline, Cochrane Collaboration Library, and Embase (period: database inception to March 2023). Randomized controlled trials enrolling patients who underwent TKR and studies examining the effect of robot-assisted rehabilitation on physical function and pain outcomes were eligible for inclusion. Eight studies (302 patients) were thus included. RESULTS: Exoskeletons significantly improved active range of motion (ROM) (SMD: 10.98, 95% confidence interval (CI): 7.81-14.16, P < .001), passive ROM (SMD: 4.11, 95% CI: 1.02-7.20, P = .009), Hospital for Special Surgery scores (SMD: 7.78, 95% CI: 5.87-9.68, P < .00001), and hospital stay length (SMD: -3.19, 95% CI: -4 to -2.38, P < .00001) compared with conventional rehabilitation. Active and passive ROM improvements suggest that exoskeletons aid knee function restoration and mobility post-TKR, whereas Hospital for Special Surgery score improvements support exoskeleton use in TKR rehabilitation. A shorter hospital stay was an important finding which could potentially reduce healthcare costs and improve outcomes. CONCLUSION: Despite the inclusion of a limited number of studies, our findings suggest that exoskeletons can enhance post-TKR rehabilitation outcomes and improve quality of life. Robot-assisted rehabilitation may be effective following TKR. Further research should confirm these findings.


Asunto(s)
Artroplastia de Reemplazo de Rodilla , Dispositivo Exoesqueleto , Rango del Movimiento Articular , Humanos , Artroplastia de Reemplazo de Rodilla/rehabilitación , Artroplastia de Reemplazo de Rodilla/métodos , Recuperación de la Función , Ensayos Clínicos Controlados Aleatorios como Asunto , Tiempo de Internación
2.
J Biomed Sci ; 31(1): 44, 2024 Apr 29.
Artículo en Inglés | MEDLINE | ID: mdl-38685037

RESUMEN

BACKGROUND: Helicobacter pylori, the main cause of various gastric diseases, infects approximately half of the human population. This pathogen is auxotrophic for cholesterol which it converts to various cholesteryl α-glucoside derivatives, including cholesteryl 6'-acyl α-glucoside (CAG). Since the related biosynthetic enzymes can be translocated to the host cells, the acyl chain of CAG likely comes from its precursor phosphatidylethanolamine (PE) in the host membranes. This work aims at examining how the acyl chain of CAG and PE inhibits the membrane functions, especially bacterial adhesion. METHODS: Eleven CAGs that differ in acyl chains were used to study the membrane properties of human gastric adenocarcinoma cells (AGS cells), including lipid rafts clustering (monitored by immunofluorescence with confocal microscopy) and lateral membrane fluidity (by the fluorescence recovery after photobleaching). Cell-based and mouse models were employed to study the degree of bacterial adhesion, the analyses of which were conducted by using flow cytometry and immunofluorescence staining, respectively. The lipidomes of H. pylori, AGS cells and H. pylori-AGS co-cultures were analyzed by Ultraperformance Liquid Chromatography-Tandem Mass Spectroscopy (UPLC-MS/MS) to examine the effect of PE(10:0)2, PE(18:0)2, PE(18:3)2, or PE(22:6)2 treatments. RESULTS: CAG10:0, CAG18:3 and CAG22:6 were found to cause the most adverse effect on the bacterial adhesion. Further LC-MS analysis indicated that the treatment of PE(10:0)2 resulted in dual effects to inhibit the bacterial adhesion, including the generation of CAG10:0 and significant changes in the membrane compositions. The initial (1 h) lipidome changes involved in the incorporation of 10:0 acyl chains into dihydro- and phytosphingosine derivatives and ceramides. In contrast, after 16 h, glycerophospholipids displayed obvious increase in their very long chain fatty acids, monounsaturated and polyunsaturated fatty acids that are considered to enhance membrane fluidity. CONCLUSIONS: The PE(10:0)2 treatment significantly reduced bacterial adhesion in both AGS cells and mouse models. Our approach of membrane remodeling has thus shown great promise as a new anti-H. pylori therapy.


Asunto(s)
Colesterol/análogos & derivados , Helicobacter pylori , Helicobacter pylori/metabolismo , Helicobacter pylori/fisiología , Ratones , Animales , Humanos , Lípidos de la Membrana/metabolismo , Línea Celular Tumoral , Infecciones por Helicobacter/tratamiento farmacológico , Infecciones por Helicobacter/microbiología , Infecciones por Helicobacter/metabolismo , Ésteres del Colesterol/metabolismo
3.
ACS Sens ; 9(1): 455-463, 2024 01 26.
Artículo en Inglés | MEDLINE | ID: mdl-38234004

RESUMEN

Selective detection of biomarkers at low concentrations in blood is crucial for the clinical diagnosis of many diseases but remains challenging. In this work, we aimed to develop an ultrasensitive immunoassay that can detect biomarkers in serum with an attomolar limit of detection (LOD). We proposed a sandwich-type heterogeneous immunosensor in a 3 × 3 well array format by integrating a resonant waveguide grating (RWG) substrate with upconversion nanoparticles (UCNPs). UCNPs were used to label a target biomarker captured by capture antibody molecules immobilized on the surface of the RWG substrate, and the RWG substrate was used to enhance the upconversion luminescence (UCL) of UCNPs through excitation resonance. The LOD of the immunosensor was greatly reduced due to the increased UCL of UCNPs and the reduction of nonspecific adsorption of detection antibody-conjugated UCNPs on the RWG substrate surface by coating the RWG substrate surface with a carboxymethyl dextran layer. The immunosensor exhibited an extremely low LOD [0.24 fg/mL (9.1 aM)] and wide detection range (1 fg/mL to 100 pg/mL) in the detection of cardiac troponin I (cTnI). The cTnI concentrations in human serum samples collected at different times during cyclophosphamide, epirubicin, and 5-fluorouracil (CEF) chemotherapy in a breast cancer patient were measured by an immunosensor, and the results showed that the CEF chemotherapy did cause cardiotoxicity in the patient. Having a higher number of wells in such an array-based biosensor, the sensor can be developed as a high-throughput diagnostic tool for clinically important biomarkers.


Asunto(s)
Técnicas Biosensibles , Nanopartículas , Humanos , Troponina I , Inmunoensayo/métodos , Nanopartículas/química , Epirrubicina , Biomarcadores
4.
Breast Cancer Res ; 25(1): 149, 2023 12 08.
Artículo en Inglés | MEDLINE | ID: mdl-38066611

RESUMEN

BACKGROUND: Based on the molecular expression of cancer cells, molecular subtypes of breast cancer have been applied to classify patients for predicting clinical outcomes and prognosis. However, further evidence is needed regarding the influence of molecular subtypes on the efficacy of radiotherapy (RT) after breast-conserving surgery (BCS), particularly in a population-based context. Hence, the present study employed a propensity-score-matched cohort design to investigate the potential role of molecular subtypes in stratifying patient outcomes for post-BCS RT and to identify the specific clinical benefits that may emerge. METHODS: From 2006 to 2019, the present study included 59,502 breast cancer patients who underwent BCS from the Taiwan National Health Insurance Research Database. Propensity scores were utilized to match confounding variables between patients with and without RT within each subtype of breast cancer, namely luminal A, luminal B/HER2-negative, luminal B/HER2-positive, basal-like, and HER2-enriched ones. Several clinical outcomes were assessed, in terms of local recurrence (LR), regional recurrence (RR), distant metastasis (DM), disease-free survival (DFS), and overall survival (OS). RESULTS: After post-BCS RT, patients with luminal A and luminal B/HER2-positive breast cancers exhibited a decrease in LR (adjusted hazard ratio [aHR] = 0.18, p < 0.0001; and, 0.24, p = 0.0049, respectively). Furthermore, reduced RR and improved DFS were observed in patients with luminal A (aHR = 0.15, p = 0.0004; and 0.29, p < 0.0001), luminal B/HER2-negative (aHR = 0.06, p = 0.0093; and, 0.46, p = 0.028), and luminal B/HER2-positive (aHR = 0.14, p = 0.01; and, 0.38, p < 0.0001) breast cancers. Notably, OS benefits were found in patients with luminal A (aHR = 0.62, p = 0.002), luminal B/HER2-negative (aHR = 0.30, p < 0.0001), basal-like (aHR = 0.40, p < 0.0001), and HER2-enriched (aHR = 0.50, p = 0.03), but not luminal B/HER2-positive diseases. Remarkably, when considering DM, luminal A patients who received RT demonstrated a lower cumulative incidence of DM than those without RT (p = 0.02). CONCLUSION: In patients with luminal A breast cancer who undergo BCS, RT could decrease the likelihood of tumor metastasis. After RT, the tumor's hormone receptor status may predict tumor control regarding LR, RR, and DFS. Besides, the HER2 status of luminal breast cancer patients may serve as an additional predictor of OS after post-BCS RT. However, further prospective studies are required to validate these findings.


Asunto(s)
Neoplasias de la Mama , Humanos , Femenino , Neoplasias de la Mama/genética , Neoplasias de la Mama/radioterapia , Neoplasias de la Mama/cirugía , Estudios de Cohortes , Mastectomía Segmentaria , Puntaje de Propensión , Receptor ErbB-2/metabolismo , Pronóstico , Estudios Retrospectivos , Recurrencia Local de Neoplasia/patología
5.
Proc Natl Acad Sci U S A ; 120(5): e2207091120, 2023 Jan 31.
Artículo en Inglés | MEDLINE | ID: mdl-36689650

RESUMEN

Galectin-4, a member of the galectin family of animal glycan-binding proteins (GBPs), is specifically expressed in gastrointestinal epithelial cells and is known to be able to bind microbes. However, its function in host-gut microbe interactions remains unknown. Here, we show that intracellular galectin-4 in intestinal epithelial cells (IECs) coats cytosolic Salmonella enterica serovar Worthington and induces the formation of bacterial chains and aggregates. Galectin-4 enchains bacteria during their growth by binding to the O-antigen of lipopolysaccharides. Furthermore, the binding of galectin-4 to bacterial surfaces restricts intracellular bacterial motility. Galectin-4 enhances caspase-1 activation and mature IL-18 production in infected IECs especially when autophagy is inhibited. Finally, orally administered S. enterica serovar Worthington, which is recognized by human galectin-4 but not mouse galectin-4, translocated from the intestines to mesenteric lymph nodes less effectively in human galectin-4-transgenic mice than in littermate controls. Our results suggest that galectin-4 plays an important role in host-gut microbe interactions and prevents the dissemination of pathogens. The results of the study revealed a novel mechanism of host-microbe interactions that involves the direct binding of cytosolic lectins to glycans on intracellular microbes.


Asunto(s)
Galectina 4 , Inflamasomas , Animales , Ratones , Humanos , Inflamasomas/metabolismo , Galectina 4/metabolismo , Células Epiteliales/metabolismo , Bacterias , Antígenos O/metabolismo
6.
Redox Biol ; 57: 102501, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-36279628

RESUMEN

Heat shock protein 90 (Hsp90) is a ubiquitous chaperone to interact with numerous proteins to regulate multiple cellular processes, especially during cell proliferation and cell cycle progression. Hsp90 exists in a high level in tumor cells and tissues, and thus serves as a prognostic biomarker or therapeutic target in cancers. We herein report that Hsp90 is subjected to S-glutathionylation, a redox-dependent modification to form a disulfide bond between the tripeptide glutathione and cysteine residues of proteins, primarily at C366 and C412 in the presence of reactive oxygen species. The modification led to the loss of the ATPase activity. The level of Hsp90 was obviously reduced by S-glutathionylation, owing to C-terminus of Hsc70-interacting protein (CHIP)-mediated ubiquitin proteasome system. S-glutathionylation of Hsp90 was found to crosstalk with its C-terminal phosphorylation of Hsp90 that impedes the binding of Hsp90 with CHIP, demonstrating the importance of chaperone code in modulating Hsp90 function. Further biophysical analyses indicated that S-glutathionylation caused structural change of Hsp90, underlying the aforementioned functional regulation. Moreover, in accordance with the analysis of 64 samples collected from patients of breast cancer, the expression level of Hsp90 inversely correlated with the glutathionylated status of Hsp90. The ratio of total expression to glutathionylated status of Hsp90 was coherent to expression of biomarkers in breast cancer sample, potentiating the prognostic value in the cancer treatment.

7.
Gut Microbes ; 14(1): 2130650, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-36206406

RESUMEN

Helicobacter pylori infection is associated with the development of several gastric diseases including gastric cancer. To reach a long-term colonization in the host stomach, H. pylori employs multiple outer membrane adhesins for binding to the gastric mucosa. However, due to the redundancy of adhesins that complement the adhesive function of bacteria, targeting each individual adhesin alone usually achieves nonideal outcomes for preventing bacterial adhesion. Here, we report that key adhesins AlpA/B and BabA/B in H. pylori are modified by glycans and display a two-step molecular weight upshift pattern from the cytoplasm to the inner membrane and from the inner membrane to the outer membrane. Nevertheless, this upshift pattern is missing when the expression of some enzymes related to lipopolysaccharide (LPS) biosynthesis, including the LPS O-antigen assembly and ligation enzymes WecA, Wzk, and WaaL, is disrupted, indicating that the underlying mechanisms and the involved enzymes for the adhesin glycosylation are partially shared with the LPS biosynthesis. Loss of the adhesin glycosylation not only reduces the protease resistance and the stability of the tested adhesins but also changes the adhesin-binding ability. In addition, mutations in the LPS biosynthesis cause a significant reduction in bacterial adhesion in the in vitro cell-line model. The current findings reveal that H. pylori employs a general protein glycosylation system related to LPS biosynthesis for adhesin modification and its biological significance. The enzymes required for adhesin glycosylation rather than the adhesins themselves are potentially better drug targets for preventing or treating H. pylori infection.


Asunto(s)
Microbioma Gastrointestinal , Infecciones por Helicobacter , Helicobacter pylori , Adhesinas Bacterianas/genética , Adhesinas Bacterianas/metabolismo , Adhesión Bacteriana , Glicosilación , Infecciones por Helicobacter/microbiología , Helicobacter pylori/genética , Humanos , Lipopolisacáridos/metabolismo , Antígenos O/metabolismo , Péptido Hidrolasas/metabolismo
8.
Org Lett ; 24(28): 5045-5050, 2022 07 22.
Artículo en Inglés | MEDLINE | ID: mdl-35816729

RESUMEN

We report the isolation and stereochemical determination of the predominant native cholesteryl 6-O-phosphatidyl α-glucoside (CPG) from Helicobacter pylori via an integrated biological and chemical strategy. The strategy employed (i) the metabolic isolation of a CPG analogue and (ii) the enzymatic degradation of the analogue to obtain the native lactobacillic acid for the stereochemical determination. The absolute stereochemistry of the acid was found to be 11R and 12S. Using the new stereochemical data, we accomplished the total synthesis of predominant native CPG and other predominant αCG derivatives.


Asunto(s)
Helicobacter pylori , Carcinógenos/metabolismo , Glucósidos
9.
Molecules ; 27(10)2022 May 18.
Artículo en Inglés | MEDLINE | ID: mdl-35630712

RESUMEN

Data from the World Health Organisation show that the global incidence of dengue infection has risen drastically, with an estimated 400 million cases of dengue infection occurring annually. Despite this worrying trend, there is still no therapeutic treatment available. Herein, we investigated short peptide fragments with a varying total number of amino acid residues (peptide fragments) from previously reported dengue virus type 2 (DENV2) peptide-based inhibitors, DN58wt (GDSYIIIGVEPGQLKENWFKKGSSIGQMF), DN58opt (TWWCFYFCRRHHPFWFFYRHN), DS36wt (LITVNPIVTEKDSPVNIEAE), and DS36opt (RHWEQFYFRRRERKFWLFFW), aided by in silico approaches: peptide-protein molecular docking and 100 ns of molecular dynamics (MD) simulation via molecular mechanics using Poisson-Boltzmann surface area (MMPBSA) and molecular mechanics generalised Born surface area (MMGBSA) methods. A library of 11,699 peptide fragments was generated, subjected to in silico calculation, and the candidates with the excellent binding affinity and shown to be stable in the DI-DIII binding pocket of DENV2 envelope (E) protein were determined. Selected peptides were synthesised using conventional Fmoc solid-phase peptide chemistry, purified by RP-HPLC, and characterised using LCMS. In vitro studies followed, to test for the peptides' toxicity and efficacy in inhibiting the DENV2 growth cycle. Our studies identified the electrostatic interaction (from free energy calculation) to be the driving stabilising force for the E protein-peptide interactions. Five key E protein residues were also identified that had the most interactions with the peptides: (polar) LYS36, ASN37, and ARG350, and (nonpolar) LEU351 and VAL354; these residues might play crucial roles in the effective binding interactions. One of the peptide fragments, DN58opt_8-13 (PFWFFYRH), showed the best inhibitory activity, at about 63% DENV2 plague reduction, compared with no treatment. This correlates well with the in silico studies in which the peptide possessed the lowest binding energy (-9.0 kcal/mol) and was maintained steadily within the binding pocket of DENV2 E protein during the MD simulations. This study demonstrates the use of computational studies to expand research on lead optimisation of antiviral peptides, thus explaining the inhibitory potential of the designed peptides.


Asunto(s)
Virus del Dengue , Dengue , Dengue/tratamiento farmacológico , Humanos , Simulación del Acoplamiento Molecular , Fragmentos de Péptidos/farmacología , Péptidos/química
10.
Front Immunol ; 13: 858894, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35281035

RESUMEN

Type-I and Type-II LacNAc are Gal-GlcNAc disaccharides bearing a ß1,3- or ß1,4-linkage respectively. They exist as the backbones of Lewis antigens that are highly expressed in several cancers. Owing to the promise of developing carbohydrate-based anti-cancer vaccines, glycan synthesis at a large scale is indeed an important task. Synthesis of Type-I and Type-II tandem repeat oligomers has been hampered by the presence of GlcNAc residues. Particularly, N-protecting group plays a determining role in affecting glycosyl donor's reactivity and acceptor's nucleophilicity. This review discusses several representative studies that assembled desirable glycans in an efficient manner, such as chemoselective one-pot synthesis and chemoenzymatic methods. Additionally, we also highlight solutions that have been offered to tackle long-lasting problems, e.g., prevention of the oxazoline formation and change of donor/acceptor reactivity. In retrospect of scientific achievements, we present the current restrictions and remaining challenges in this less explored frontier.


Asunto(s)
Oligosacáridos , Polisacáridos , Antígenos de Neoplasias , Disacáridos , Antígenos del Grupo Sanguíneo de Lewis , Oligosacáridos/química , Polisacáridos/química
11.
Proc Natl Acad Sci U S A ; 118(30)2021 07 27.
Artículo en Inglés | MEDLINE | ID: mdl-34301890

RESUMEN

Cytosolic lipopolysaccharides (LPSs) bind directly to caspase-4/5/11 through their lipid A moiety, inducing inflammatory caspase oligomerization and activation, which is identified as the noncanonical inflammasome pathway. Galectins, ß-galactoside-binding proteins, bind to various gram-negative bacterial LPS, which display ß-galactoside-containing polysaccharide chains. Galectins are mainly present intracellularly, but their interactions with cytosolic microbial glycans have not been investigated. We report that in cell-free systems, galectin-3 augments the LPS-induced assembly of caspase-4/11 oligomers, leading to increased caspase-4/11 activation. Its carboxyl-terminal carbohydrate-recognition domain is essential for this effect, and its N-terminal domain, which contributes to the self-association property of the protein, is also critical, suggesting that this promoting effect is dependent on the functional multivalency of galectin-3. Moreover, galectin-3 enhances intracellular LPS-induced caspase-4/11 oligomerization and activation, as well as gasdermin D cleavage in human embryonic kidney (HEK) 293T cells, and it additionally promotes interleukin-1ß production and pyroptotic death in macrophages. Galectin-3 also promotes caspase-11 activation and gasdermin D cleavage in macrophages treated with outer membrane vesicles, which are known to be taken up by cells and release LPSs into the cytosol. Coimmunoprecipitation confirmed that galectin-3 associates with caspase-11 after intracellular delivery of LPSs. Immunofluorescence staining revealed colocalization of LPSs, galectin-3, and caspase-11 independent of host N-glycans. Thus, we conclude that galectin-3 amplifies caspase-4/11 oligomerization and activation through LPS glycan binding, resulting in more intense pyroptosis-a critical mechanism of host resistance against bacterial infection that may provide opportunities for new therapeutic interventions.


Asunto(s)
Caspasas/metabolismo , Galectina 3/metabolismo , Inflamasomas/inmunología , Inflamación/inmunología , Lipopolisacáridos/metabolismo , Macrófagos/inmunología , Animales , Citosol/metabolismo , Galectina 3/genética , Inflamasomas/metabolismo , Inflamación/metabolismo , Inflamación/patología , Macrófagos/metabolismo , Macrófagos/patología , Ratones , Ratones Endogámicos C57BL , Piroptosis
12.
Tzu Chi Med J ; 33(2): 128-134, 2021.
Artículo en Inglés | MEDLINE | ID: mdl-33912409

RESUMEN

Factors, such as hormonal changes in postmenopausal women, natural aging degeneration, race, gender, body size, lifestyle, physical activity, sunlight, dietary intake, medications, or other environmental issues, can affect the rate of bone formation or reabsorption, cause changes in bone mineral content, and influence the development of osteoporosis. Do vegetarian diets adversely affect bone mineral density (BMD)? Among postmenopausal Buddhists, long-term practitioners of vegan vegetarian were found to have a higher risk exceeding the lumbar fracture threshold and a lower level of hip BMD after controlling for other variables. However, results of several prospective longitudinal studies failed to show a harmful effect of vegetarianism on bone health. In the Taiwanese adult population, researchers also did not find that a vegetarian diet significantly affects age-related BMD decline. Due to the various levels of nutrients in the diet (such as protein, alkali, calcium, Vitamin K, and phytoestrogens) and major lifestyle factors (such as smoking and physical exercise), determining the impact of a vegetarian diet on bone health is very complex. Good-quality vegetarian food can provide a healthy foundation for building and maintaining healthy bones and preventing fractures.

13.
Commun Biol ; 4(1): 280, 2021 03 04.
Artículo en Inglés | MEDLINE | ID: mdl-33664385

RESUMEN

Irinotecan inhibits cell proliferation and thus is used for the primary treatment of colorectal cancer. Metabolism of irinotecan involves incorporation of ß-glucuronic acid to facilitate excretion. During transit of the glucuronidated product through the gastrointestinal tract, an induced upregulation of gut microbial ß-glucuronidase (GUS) activity may cause severe diarrhea and thus force many patients to stop treatment. We herein report the development of uronic isofagomine (UIFG) derivatives that act as general, potent inhibitors of bacterial GUSs, especially those of Escherichia coli and Clostridium perfringens. The best inhibitor, C6-nonyl UIFG, is 23,300-fold more selective for E. coli GUS than for human GUS (Ki = 0.0045 and 105 µM, respectively). Structural evidence indicated that the loss of coordinated water molecules, with the consequent increase in entropy, contributes to the high affinity and selectivity for bacterial GUSs. The inhibitors also effectively reduced irinotecan-induced diarrhea in mice without damaging intestinal epithelial cells.


Asunto(s)
Bacterias/efectos de los fármacos , Colon/microbiología , Diarrea/prevención & control , Inhibidores Enzimáticos/farmacología , Microbioma Gastrointestinal/efectos de los fármacos , Glucuronidasa/antagonistas & inhibidores , Iminopiranosas/farmacología , Irinotecán , Ácidos Urónicos/farmacología , Animales , Bacterias/enzimología , Línea Celular , Diarrea/inducido químicamente , Diarrea/microbiología , Modelos Animales de Enfermedad , Femenino , Glucuronidasa/metabolismo , Humanos , Ratones Endogámicos BALB C
14.
Eur J Med Chem ; 208: 112707, 2020 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-32942185

RESUMEN

Ligand 1 was the first reported example of monomeric high-affinity synthetic CD22 ligand that regulated B cell activation in vitro, augmented antibody production and regulated immune responses in mice. Replacing O-glycoside linkage of 1 by nitrogen of triazole by click reaction afforded compounds which are as potent as the parent compound. The synthesis of the new compounds is straightforward with fewer synthetic steps and higher yield. Such a strategy provided stable ligand that can bind avidly and can be conjugated to drugs for B-cell targeting or multimeric formation. The new compounds were screened for their affinity to CD22, using surface plasmon resonance (SPR). Compound 12 was obtained as a bioisosteric analogue and an anomerically stable imitation of 1. It was, also, screened for MAG to test for selectivity and analyzed by molecular docking and dynamic simulation to explore the potential binding modes and source of selectivity within CD22. Our results could enable the development of small molecule drug capable of modulating the activity of CD22 in autoimmune diseases and malignancies derived from B-cells.


Asunto(s)
Lectina 2 Similar a Ig de Unión al Ácido Siálico/metabolismo , Ácidos Siálicos/farmacología , Triazoles/farmacología , Animales , Células HEK293 , Humanos , Ligandos , Ratones , Simulación del Acoplamiento Molecular , Unión Proteica , Ácidos Siálicos/síntesis química , Ácidos Siálicos/metabolismo , Triazoles/síntesis química , Triazoles/metabolismo
15.
Angew Chem Int Ed Engl ; 59(32): 13537-13541, 2020 08 03.
Artículo en Inglés | MEDLINE | ID: mdl-32343875

RESUMEN

The 1,3-enyne moiety is commonly found in cyclohexanoid natural products produced by endophytic and plant pathogenic fungi. Asperpentyn (1) is a 1,3-enyne-containing cyclohexanoid terpenoid isolated from Aspergillus and Pestalotiopsis. The genetic basis and biochemical mechanism of 1,3-enyne biosynthesis in 1, and other natural products containing this motif, has remained enigmatic despite their potential ecological roles. Identified here is the biosynthetic gene cluster and characterization of two crucial enzymes in the biosynthesis of 1. A P450 monooxygenase that has a dual function, to first catalyze dehydrogenation of the prenyl chain to generate a cis-diene intermediate and then serve as an acetylenase to yield an alkyne moiety, and thus the 1,3-enyne, was discovered. A UbiA prenyltransferase was also characterized and it is unusual in that it favors transferring a five-carbon prenyl chain, rather than a polyprenyl chain, to a p-hydroxybenzoic acid acceptor.


Asunto(s)
Alquinos/metabolismo , Sistema Enzimático del Citocromo P-450/metabolismo , Dimetilaliltranstransferasa/metabolismo , Proteínas Fúngicas/metabolismo , Terpenos/metabolismo , Sistema Enzimático del Citocromo P-450/genética , Dimetilaliltranstransferasa/genética , Proteínas Fúngicas/genética , Hongos/enzimología , Hongos/genética , Hongos/metabolismo , Estructura Molecular , Familia de Multigenes
16.
Commun Biol ; 3(1): 120, 2020 03 13.
Artículo en Inglés | MEDLINE | ID: mdl-32170208

RESUMEN

Helicobacter pylori, the most common etiologic agent of gastric diseases including gastric cancer, is auxotrophic for cholesterol and has to hijack it from gastric epithelia. Upon uptake, the bacteria convert cholesterol to cholesteryl 6'-O-acyl-α-D-glucopyranoside (CAG) to promote lipid raft clustering in the host cell membranes. However, how CAG appears in the host to exert the pathogenesis still remains ambiguous. Herein we identified hp0499 to be the gene of cholesteryl α-D-glucopyranoside acyltransferase (CGAT). Together with cholesteryl glucosyltransferase (catalyzing the prior step), CGAT is secreted via outer membrane vesicles to the host cells for direct synthesis of CAG. This significantly enhances lipid rafts clustering, gathers adhesion molecules (including Lewis antigens and integrins α5, ß1), and promotes more bacterial adhesion. Furthermore, the clinically used drug amiodarone was shown as a potent inhibitor of CGAT to effectively reduce the bacterial adhesion, indicating that CGAT is a potential target of therapeutic intervention.


Asunto(s)
Aciltransferasas/metabolismo , Adhesión Bacteriana/genética , Proteínas Bacterianas/metabolismo , Colesterol/análogos & derivados , Mucosa Gástrica/microbiología , Helicobacter pylori/enzimología , Aciltransferasas/antagonistas & inhibidores , Aciltransferasas/genética , Amiodarona/farmacología , Adhesión Bacteriana/efectos de los fármacos , Proteínas Bacterianas/antagonistas & inhibidores , Proteínas Bacterianas/genética , Línea Celular Tumoral , Colesterol/metabolismo , Epitelio/microbiología , Técnicas de Inactivación de Genes , Genes Bacterianos , Glucosiltransferasas/metabolismo , Humanos , Integrina alfa5/metabolismo , Integrina beta1/metabolismo , Antígenos del Grupo Sanguíneo de Lewis/metabolismo , Microdominios de Membrana/metabolismo
17.
Int Urol Nephrol ; 51(11): 2015-2025, 2019 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-31578673

RESUMEN

PURPOSE: Mammalian target of rapamycin (mTOR) inhibitors were previously considered a potential therapy for autosomal dominant polycystic kidney disease (ADPKD), but prior studies remained controversial about their efficacy. We performed an updated meta-analysis regarding the therapeutic and adverse effects of mTOR inhibitors in patients with ADPKD. METHODS: We systematically searched Cochrane Library, PubMed, EMBASE, and Medline for randomized controlled trials (RCTs) comparing mTOR inhibitors to placebo in ADPKD patients up to August 2019. We calculated weighted mean differences (WMDs) for total kidney volume (TKV), estimated glomerular filtration rates (eGFRs), and weighted odds ratios (ORs) for treatment-related complications between the treatment and the placebo groups, using the random effects model. RESULTS: We retrieved a total of 9 RCTs enrolling 784 ADPKD patients receiving rapamycin, sirolimus, or everolimus between 2009 and 2016. The WMDs of TKV and eGFR from baseline to the last measurement were - 31.54 mL (95% confidence interval [CI] - 76.79 to 13.71 mL) and 2.81 mL/min/1.73 m2 (95% CI - 1.85 to 7.46 mL/min/1.73 m2), respectively. Patients receiving mTOR inhibitors had a significantly increased risk of any adverse effects (OR 5.92, 95% CI 3.53-9.94), with the most common ones being aphthous stomatitis (OR 15.45, 95% CI 9.68-24.66) and peripheral edema (OR 3.49, 95% CI 1.31-9.27) compared to placebo users. CONCLUSIONS: mTOR inhibitors did not significantly influence renal progression in patients with ADPKD, but were associated with a higher risk of complications. Whether mTOR inhibitors can be an add-on option or second-line agents remain undetermined.


Asunto(s)
Riñón Poliquístico Autosómico Dominante/tratamiento farmacológico , Serina-Treonina Quinasas TOR/antagonistas & inhibidores , Humanos , Serina-Treonina Quinasas TOR/efectos adversos , Resultado del Tratamiento
18.
ACS Sens ; 4(7): 1816-1824, 2019 07 26.
Artículo en Inglés | MEDLINE | ID: mdl-31251034

RESUMEN

The determination of cell confluency and subculture timing for cell culture consistency is crucial in the field of cell-based research, but there is no universal standard concerning optimal confluence. In this study, gold nanodot arrays on glass substrates were used as culture substrates, and their spectral shifts of localized surface plasmon resonance (LSPR) were employed to monitor cell growth and quantify cell confluency. Experiments including cell counting, metabolic activity, focal adhesion, and cell cycle were also performed to confirm the cell growth monitoring accuracy of the LSPR signals. The LSPR signal exhibited the same trends like the increase of cell numbers and cell metabolic activity and reached the maximum as the cell growth achieved confluency, suggesting its great capability as an effective indicator to predict suitable subculture timing. The proposed sensing approach is a noninterventional, nondestructive, real-time, and useful tool to help biologists quantify the optimal subculture timing, achieve cell culture consistency, and obtain reproducible experimental results efficiently.


Asunto(s)
Técnicas de Cultivo de Célula/métodos , Células Epiteliales/metabolismo , Puntos Cuánticos/química , Citoesqueleto de Actina/metabolismo , Recuento de Células/métodos , Ciclo Celular/fisiología , Línea Celular , Proliferación Celular/fisiología , Adhesiones Focales/metabolismo , Oro/química , Oro/toxicidad , Humanos , Puntos Cuánticos/toxicidad , Resonancia por Plasmón de Superficie/métodos
19.
Glycobiology ; 29(2): 151-162, 2019 02 01.
Artículo en Inglés | MEDLINE | ID: mdl-30289459

RESUMEN

Galectin-8, a beta-galactoside-binding lectin, is upregulated in the gastric tissues of rhesus macaques infected with Helicobacter pylori. In this study, we found that H. pylori infection triggers intracellular galectin-8 aggregation in human-derived AGS gastric epithelial cells, and that these aggregates colocalize with lysosomes. Notably, this aggregation is markedly reduced following the attenuation of host O-glycan processing. This indicates that H. pylori infection induces lysosomal damage, which in turn results in the accumulation of cytosolic galectin-8 around damaged lysosomes through the recognition of exposed vacuolar host O-glycans. H. pylori-induced galectin-8 aggregates also colocalize with autophagosomes, and galectin-8 ablation reduces the activation of autophagy by H. pylori. This suggests that galectin-8 aggregates may enhance autophagy activity in infected cells. We also observed that both autophagy and NDP52, an autophagy adapter, contribute to the augmentation of galectin-8 aggregation by H. pylori. Additionally, vacuolating cytotoxin A, a secreted H. pylori cytotoxin, may contribute to the increased galectin-8 aggregation and elevated autophagy response in infected cells. Collectively, these results suggest that H. pylori promotes intracellular galectin-8 aggregation, and that galectin-8 aggregation and autophagy may reciprocally regulate each other during infection.


Asunto(s)
Células Epiteliales/metabolismo , Galectinas/metabolismo , Mucosa Gástrica/metabolismo , Helicobacter pylori/metabolismo , Lisosomas/metabolismo , Polisacáridos/metabolismo , Autofagia , Mucosa Gástrica/patología , Humanos , Agregado de Proteínas
20.
Sci Rep ; 8(1): 3821, 2018 02 28.
Artículo en Inglés | MEDLINE | ID: mdl-29491476

RESUMEN

Tissue stroma is known to be important in regulating Hp-mediated inflammation, but its interaction with Hp and dendritic cells (DCs) remains to be determined. To this end, the potential crosstalk between H. pylori (Hp) infected gastric stromal cells (Hp-GSCs) and DCs was investigated. Primary GSCs from cancerous and adjacent normal tissues were generated from gastric cancer patients, and monocyte-derived DCs were obtained from healthy individuals. Levels of cytokines and prostaglandin E2 (PGE2) were measured by ELISA, and C-type lectin expression in GSCs was assessed by flow cytometry and immunohistochemistry. In a trans-well co-culture system, significantly upregulated DC-derived IL-23 expression was found when DCs were co-cultured with Hp-infected GSCs (Hp-GSCs). Further, PGE2 from Hp-GSCs was discovered to possess the priming effect, which could be inhibited by anti-COLEC12 (Collectin subfamily member 12) Abs, COLEC12 knockdown or when alpha3-fucosyltransferase-null (futB; HP0651) strain of Hp was used. Also, the expression of COLEC12 was co-localized with CD90+ stromal cells in cancerous tissues. Hp-GSCs-conditioned DCs were able to induce the expression of IL-17 from CD4+ T cells, which could be inhibited by IL-23-neutralizing Abs. These results suggested the importance of COLEC12 as a receptor involved in Hp-stromal cell interaction and its subsequent conditioning effect on DCs.


Asunto(s)
Colectinas/metabolismo , Dinoprostona/metabolismo , Helicobacter pylori/fisiología , Inmunidad Innata , Subtipo EP2 de Receptores de Prostaglandina E/metabolismo , Subtipo EP4 de Receptores de Prostaglandina E/metabolismo , Receptores Depuradores/metabolismo , Neoplasias Gástricas/inmunología , Linfocitos T CD4-Positivos/inmunología , Células Dendríticas/inmunología , Regulación Neoplásica de la Expresión Génica , Humanos , Interleucina-23/metabolismo , Neoplasias Gástricas/microbiología , Neoplasias Gástricas/patología , Células del Estroma/metabolismo , Células del Estroma/microbiología , Células del Estroma/patología , Células Th17/inmunología
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