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1.
Vet Res Commun ; 48(5): 2963-2976, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-38958817

RESUMO

The larvae of Cephalopina titillator cause nasopharyngeal myiasis in camels, which parasitize the living tissues of the nasal and paranasal sinuses, pharynx, and larynx. C. titillator infestation adversely affects camel health, meat, and milk production, and can even cause death. In our study, to improve the immunodiagnosis of camel nasal myiasis, a sensitive and specific enzyme-linked immunosorbent assay (ELISA) was developed and evaluated using the Concanavalin-A (Con-A) affinity purification for the C. titillator-N-acetylglucosamine (Ct-GlucNAc) glycoprotein fraction from third larval instars as an antigen for detecting C. titillator antibodies. Crude antigens were prepared from larval instars of C. titillator and evaluated by indirect ELISA. The third C. titillator larval antigen (L3Ct) had the highest protein content (P < 0.001) and the best diagnostic value; chi-square = 235 (P < 0.001). Four glycoprotein fractions were purified separately from the L3Ct antigen by Con-A purification and evaluated. The Ct-GlucNAc glycoprotein fraction was the fraction of choice with the highest diagnostic accuracy (P < 0.05). Using Ct-GlucNAc as a coating antigen, indirect ELISA showed a 99.3% sensitivity for positive results in camel myiasis samples and 100% specificity for negative results in healthy camel samples. The diagnostic accuracy was 99.7%, and no cross reactivity was detected for other parasitic diseases. The indirect ELISA results were confirmed by the western immunoblotting which was characterized by comparing sera from naturally infested dromedary camels with C. titillator, sera from healthy camels and sera from camels with other parasitic infections (Echinococcus granulosus, Fasciola gigantica, Hard ticks; Hyalomma dromedarii, Trichostronglid sp., Eimeria spp., and Cryptosporidium sp.). Immunoreactive antigenic bands of 63, 50, 30 and 18 kDa were predominantly detected in sera from camels with nasopharyngeal myiasis and didn't react with healthy and camel's sera from other parasitic infections. However, seven immunoreactive bands appeared at 120, 70, 63, 48, 35, 29, and 19 kDa in the crude L3Ct antigen. In addition, a positive rate of C. titillator immunodiagnosis was detected by indirect ELISA (48.6%, chi-square = 483, P < 0.001), which was significantly greater than that of postmortem diagnosis (31%). In conclusion, the current study introduces a new diagnostic immunoaffinity glycoprotein fraction of C. titillator 3rd larval instar-based ELISA as a highly accurate, simple and fast method to detect specific antibodies of nasal myiasis in camels.


Assuntos
Camelus , Ensaio de Imunoadsorção Enzimática , Glicoproteínas , Larva , Miíase , Testes Sorológicos , Animais , Camelus/parasitologia , Ensaio de Imunoadsorção Enzimática/veterinária , Glicoproteínas/imunologia , Glicoproteínas/isolamento & purificação , Miíase/veterinária , Miíase/diagnóstico , Miíase/parasitologia , Testes Sorológicos/veterinária , Testes Sorológicos/métodos , Egito , Sensibilidade e Especificidade , Dípteros/imunologia
2.
Artigo em Inglês | MEDLINE | ID: mdl-38716217

RESUMO

Background: Serine/threonine kinase 1 (PIM1) plays a crucial role in cell growth, differentiation, and apoptosis. However, its role in the pathogenesis of concanavalin A (ConA)-induced acute hepatitis is not well understood. PIM1 kinase inhibitor can reduce the expression of PIM1. This study aims to investigate the effects of PIM1 kinase inhibitor and its protective mechanism in ConA-induced acute hepatitis. Methods: C57/BL six mice were injected with ConA (20, 15, and 12 mg/kg) to induce acute hepatitis, and PIM1 kinase inhibitor SMI-4a (60 mg/kg) was administered orally 24 h before ConA injection. The survival rate of the mice was observed after ConA injection. The levels of serum aspartate aminotransferase (AST) and alanine aminotransferase (ALT) were measured. Serum inflammatory factors were detected by enzyme-linked immunosorbent assay (ELISA). Hematoxylin-eosin (HE) staining was performed on liver tissue collected at different time points. The major cytokines expression in liver tissue was detected by quantitative real-time polymerase chain reaction (qRT-PCR). The number of macrophages, T-cell and neutrophils in liver tissue were detected by flow cytometry (FCM). PIM1 in liver tissue was detected by western blot (WB) and qRT-PCR. SMI-4a (80 µM) was pretreated for 24 h and ConA (400 µg/mL) was stimulated for 12 h in RAW264.7 cell model. Phosphorylated p65 (p-p65) and cleaved caspase-3 (c-caspase-3) in liver tissue and macrophages were detected by WB. Results: Different concentrations of ConA caused different acute hepatitis mortality, 12 mg/kg concentration within 24 h of the mortality showed a gradient increase. The levels of AST and ALT increased significantly at 12 h after ConA injection. PIM1 expression was upregulated at 12 h. SMI-4a can suppress the PIM1 expression. SMI-4a suppressed cytokines production, AST, and ALT in ConA-treated serum. SMI-4a suppressed the major cytokines in liver tissue. Tests in liver tissue showed that SMI-4a reduced the number of T cells, neutrophils, and macrophages. SMI-4a inhibited the inflammatory response by downregulating the expression of p-p65. Meanwhile, apoptosis was decreased by decreasing the expression of c-caspase-3. Conclusions: In conclusion, the protective effect of SMI-4a against acute hepatitis is by reducing the inflammatory response and apoptosis. These findings suggest that SMI-4a may have therapeutic potential in the treatment of autoimmune hepatitis.

3.
Int J Pharm ; 659: 124250, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38777304

RESUMO

The smart oral administration Insulin device has the potential to improve glycemic management. It can reduce the risk of hypoglycemia associated with exogenous Insulin (INS) therapy while also avoiding many of the disadvantages associated with subcutaneous injections. Furthermore, diabetes mellitus (DM) is an endocrine illness characterized by inflammation, and it is critical to minimize the amount of inflammatory markers in diabetic patients while maintaining average blood glucose. In this study, a responsive nanosystem vitamin B12-Fucoidan-Concanavalin A (VB12-FU-ConA NPs) with anti-inflammatory action was developed for smart oral delivery of Insulin. Con A has high sensitivity and strong specificity as a glucose-responsive material. Fucoidan has anti-inflammatory, immunomodulatory, and hypoglycemic functions, and it can bind to Con A to form a reversible complex. Under high glucose conditions, free glucose competitively binds to Con A, which swells the nanocarrier and promotes Insulin release. Furthermore, in the low pH environment of the gastrointestinal tract, positively charged VB12 and anionic fucoidan bind tightly to protect the Insulin wrapped in the carrier, and VB12 can also bind to intestinal epithelial factors to improve transit rate, thereby promoting INS absorption. In vitro tests showed that the release of nanoparticles in hyperglycemic solutions was significantly higher than the drug release in normoglycemic conditions. Oral delivery of the nanosystems dramatically lowered blood glucose levels in type I diabetic mice (T1DM) during in vivo pharmacodynamics, minimizing the risk of hypoglycemia. Blood glucose levels reached a minimum of 8.1 ± 0.4 mmol/L after 8 h. Administering the nanosystem orally notably decreased the serum levels of tumor necrosis factor-α (TNF-α) and interleukin-6 (IL-6) in diabetic mice. The nano delivery system can be degraded and metabolized in the intestinal tract after being taken orally, demonstrating good biodegradability and biosafety. In conclusion, the present study showed that VB12-FU-ConA nanocarriers are expected to be a novel system for rationalizing blood glucose.


Assuntos
Anti-Inflamatórios , Glicemia , Diabetes Mellitus Experimental , Hipoglicemiantes , Insulina , Polissacarídeos , Animais , Polissacarídeos/administração & dosagem , Polissacarídeos/química , Glicemia/efeitos dos fármacos , Glicemia/análise , Administração Oral , Insulina/administração & dosagem , Insulina/farmacocinética , Hipoglicemiantes/administração & dosagem , Hipoglicemiantes/farmacocinética , Hipoglicemiantes/farmacologia , Camundongos , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Anti-Inflamatórios/farmacocinética , Diabetes Mellitus Experimental/tratamento farmacológico , Diabetes Mellitus Experimental/sangue , Masculino , Vitamina B 12/administração & dosagem , Nanopartículas/administração & dosagem , Liberação Controlada de Fármacos , Portadores de Fármacos/química , Humanos
4.
Protein J ; 43(3): 559-576, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38615284

RESUMO

In this study, we purified a lectin isolated from the seeds of Dioclea bicolor (DBL) via affinity purification. Electrophoresis analysis revealed that DBL had three bands, α, ß, and γ chains, with molecular masses of approximately 29, 14, and 12 kDa, respectively. Gel filtration chromatography revealed that the native form of DBL had a molecular mass of approximately 100 kDa, indicating that it is a tetramer. Interestingly, DBL-induced hemagglutination was inhibited by several glucosides, mannosides, ampicillin, and tetracycline with minimum inhibitory concentration (MIC) values of 1.56-50 mM. Analysis of the complete amino acid sequence of DBL revealed the presence of 237 amino acids with high similarity to other Diocleinae lectins. Circular dichroism showed the prominent ß-sheet secondary structure of DBL. Furthermore, DBL structure prediction revealed a Discrete Optimized Protein Energy (DOPE) score of -26,642.69141/Normalized DOPE score of -1.84041. The DBL monomer was found to consist a ß-sandwich based on its 3D structure. Molecular docking showed the interactions between DBL and α-D-glucose, N-acetyl-D-glucosamine, α-D-mannose, α-methyl-D-mannoside, ampicillin, and tetracycline. In addition, DBL showed antimicrobial activity with an MIC of 125 µg/mL and exerted synergistic effects in combination with ampicillin and tetracycline (fractional inhibitory concentration index ≤ 0.5). Additionally, DBL significantly inhibited biofilm formation and showed no toxicity in murine fibroblasts (p < 0.05). These results suggest that DBL exhibits antimicrobial activity and works synergistically with antibiotics.


Assuntos
Antibacterianos , Dioclea , Lectinas de Plantas , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/isolamento & purificação , Camundongos , Animais , Lectinas de Plantas/química , Lectinas de Plantas/farmacologia , Lectinas de Plantas/isolamento & purificação , Dioclea/química , Simulação de Acoplamento Molecular , Testes de Sensibilidade Microbiana , Ampicilina/farmacologia , Ampicilina/química
5.
Int Immunopharmacol ; 129: 111618, 2024 Mar 10.
Artigo em Inglês | MEDLINE | ID: mdl-38354508

RESUMO

BACKGROUND: Acute hepatitis is a progressive inflammatory disorder that can lead to liver failure. Endothelial permeability is the vital pathophysiological change involved in infiltrating inflammatory factors. DDX24 has been implicated in immune signaling. However, the precise role of DDX24 in immune-mediated hepatitis remains unclear. Here, we investigate the phenotype of endothelium-targeted Ddx24 conditional knockout mice with Concanavalin A (ConA)-induced hepatitis. METHODS: Mice with homozygous endothelium-targeted Ddx24 conditional knockout (Ddx24flox/flox; Cdh5-Cre+) were established using the CRISPR/Cas9 mediated Cre-loxP system. We investigated the biological functions of endothelial cells derived from transgenic mice and explored the effects of Ddx24 in mice with ConA-induced hepatitis in vivo. The mass spectrometry was performed to identify the differentially expressed proteins in liver tissues of transgenic mice. RESULT: We successfully established mice with endothelium-targeted Ddx24 conditional knockout. The results showed migration and tube formation potentials of murine aortic endothelial cells with DDX24 silencing were significantly promoted. No differences were observed between Ddx24flox/flox; Cdh5-Cre+ and control regarding body weight and length, pathological tissue change and embryogenesis. We demonstrated Ddx24flox/flox; Cdh5-Cre+ exhibited exacerbation of ConA-induced hepatitis by up-regulating TNF-α and IFN-γ. Furthermore, endothelium-targeted Ddx24 conditional knockout caused vascular hyper-permeability in ConA-injected mice by down-regulating vascular integrity-associated proteins. Mechanistically, we identified Ddx24 might regulate immune-mediated hepatitis by inflammation-related permeable barrier pathways. CONCLUSION: These findings prove that endothelium-targeted Ddx24 conditional knockout exacerbates ConA-induced hepatitis in mice because of vascular hyper-permeability. The findings indicate a crucial role of DDX24 in regulating immune-mediated hepatitis, suggesting DDX24 as a potential therapeutic target in the disorder.


Assuntos
Células Endoteliais , Hepatite , Animais , Camundongos , Concanavalina A/toxicidade , Células Endoteliais/metabolismo , Endotélio/metabolismo , Camundongos Endogâmicos C57BL , Camundongos Knockout , Camundongos Transgênicos
6.
Arch Microbiol ; 206(1): 54, 2024 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-38180520

RESUMO

Pseudomonas aeruginosa is an opportunistic bacterium that can form a biofilm with the ability to colonize different surfaces and for increasing resistance to antibiotics. An alternative to solve this problem may be the use of non-glucose/mannose glycosylated proteins from Melipona beecheii honey, which are capable of inhibiting the growth of this pathogen. In this work, the antibiofilm activity of the conA-unbound protein fraction (F1) from M. beecheii was evaluated. The crude protein extract (CPE) and the F1 fraction inhibited the P. aeruginosa biofilm growth above 80% at 4 and 1.3 µg/mL, respectively. These proteins affected the structure of the biofilm, as well as fleQ and fleR gene expressions involved in the formation and regulation of the P. aeruginosa biofilm. The results demonstrated that the F1 fraction proteins of M. beecheii honey inhibit and affect the formation of the P. aeruginosa biofilm.


Assuntos
Mel , Infecções por Pseudomonas , Abelhas , Animais , Pseudomonas aeruginosa/genética , Antibacterianos/farmacologia , Biofilmes , Concanavalina A
7.
Int J Mol Sci ; 24(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37685946

RESUMO

Research in the treatment of type 1 diabetes has been addressed into two main areas: the development of "intelligent insulins" capable of auto-regulating their own levels according to glucose concentrations, or the exploitation of artificial intelligence (AI) and its learning capacity, to provide decision support systems to improve automated insulin therapy. This review aims to provide a synthetic overview of the current state of these two research areas, providing an outline of the latest development in the search for "intelligent insulins," and the results of new and promising advances in the use of artificial intelligence to regulate automated insulin infusion and glucose control. The future of insulin treatment in type 1 diabetes appears promising with AI, with research nearly reaching the possibility of finally having a "closed-loop" artificial pancreas.


Assuntos
Diabetes Mellitus Tipo 1 , Insulina , Humanos , Diabetes Mellitus Tipo 1/tratamento farmacológico , Inteligência Artificial , Insulina Regular Humana , Inteligência
8.
Front Microbiol ; 14: 1236599, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37692407

RESUMO

Objectives: Lipoarabinomannan (LAM), an abundant cell wall glycolipid of mycobacteria including Mycobacterium tuberculosis (Mtb), is a promising TB diagnostic marker. The current commercially available urine LAM assays are not sufficiently sensitive, and more novel detection strategies are urgently needed to fill the current diagnostic gap. Methods: A proteinase K-pretreated Concanavalin A (ConA)-based ELISA assay was developed. Diagnostic performance was assessed by several bacterial strains and clinical urine samples. Results: The limit of detection (LoD) of the assay against ManLAM was 6 ng/ml. The assay reacted strongly to Mtb H37Rv and M. bovis BCG, intermediately to M. smegmatis mc2155, and weakly to four non-mycobacteria pathogens. This method could distinguish TB patients from healthy controls (HCs) and close contacts (CCs) in 71 urine samples treated with proteinase K, which increases urine LAM antibody reactiveness. In TB+HIV+ and TB+HIV- patients, the sensitivity was 43.8 and 37.5%, respectively, while the specificity was 100.0%. The areas under ROC curves (AUCs) were 0.74 and 0.82, respectively. Conclusion: This study implies that ConA can be paired with antibodies to detect LAM. Proteinase K treatment could effectively enhance the sensitivity by restoring the reactiveness of antibodies to LAM.

9.
Regen Ther ; 22: 68-78, 2023 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-36712959

RESUMO

Heart failure is caused by various factors, making the underlying pathogenic mechanisms difficult to identify. Since cardiovascular disease tends to worsen over time, early diagnosis is key for treatment. In addition, understanding the qualitative changes in the heart associated with aging, where information on the direct influences of aging on cardiovascular disease is limited, would also be useful for treatment and diagnosis. To fill these research gaps, the focus of our study was to detect the structural and functional molecular changes associated with the heart over time, with a focus on glycans, which reflect the type and state of cells. METHODS: We investigated glycan localization in the cardiac tissue of normal mice and their alterations during aging, using evanescent-field fluorescence-assisted lectin microarray, a technique based on lectin-glycan interaction, and lectin staining. RESULTS: The glycan profiles in the left ventricle showed differences between the luminal side (medial) and wall side (lateral) regions. The medial region was characterized by the presence of sialic acid residues. Moreover, age-related changes in glycan profiles were observed at a younger age in the medial region. The difference in the age-related decrease in the level of α-galactose stained with Griffonia simplicifolia lectin-IB4 in different regions of the left ventricle suggests spatiotemporal changes in the number of microvessels. CONCLUSIONS: The glycan profile, which retains diverse glycan structures, is supported by many cell populations, and maintains cardiac function. With further research, glycan localization and changes have the potential to be developed as a marker of the signs of heart failure.

10.
Clin Exp Med ; 23(6): 2167-2179, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-36454447

RESUMO

Activation of T cells and pro-inflammatory cytokines are essential for human autoimmune hepatitis. RAGE is one of the receptors for the inflammatory alarm molecule high mobility group box 1 (HMGB1), and it is involved in autoimmune hepatitis. However, the molecular mechanism of RAGE in the context of autoimmune hepatitis remains elusive. This study aimed to identify the function and mechanism of RAGE in autoimmune hepatitis. The role and underlying mechanisms of RAGE signaling-driven immune inflammatory response in ConA-induced experimental hepatitis were examined using the RAGE-deficient mice. We found that the RAGE deficiency protected the mouse from liver inflammatory injury caused by the ConA challenge. mRNA expression of VCAM-1, IL-6, and TNF-α within the livers is markedly decreased in RAGE-deficient mice compared to wild-type mice. In parallel, RAGE deficiency leads to reduced levels of the serum pro-inflammatory cytokines IL-6 and TNF-α as compared with wild-type control mice. RAGE-deficient mice exhibit increased hepatic NK cells and decreased CD4+ T cells compared with wild-type control mice. Notably, in vivo blockade of IL-6 in wild-type mice significantly protected mice from ConA-induced hepatic injury. Furthermore, RAGE deficiency impaired IL-6 production and was associated with decreased expression of Arid5a in liver tissues, a half-life IL-6 mRNA regulator. RAGE signaling is important in regulating the development of autoimmune hepatitis. Immune regulation of RAGE may represent a novel therapeutic strategy to prevent immune-mediated liver injury.


Assuntos
Hepatite Autoimune , Animais , Camundongos , Citocinas/metabolismo , Proteínas de Ligação a DNA , Interleucina-6/genética , Fígado , RNA Mensageiro , Fatores de Transcrição , Fator de Necrose Tumoral alfa/metabolismo
11.
ACS Appl Bio Mater ; 5(12): 5877-5886, 2022 12 19.
Artigo em Inglês | MEDLINE | ID: mdl-36417663

RESUMO

Label-free detection of pathogens is of major concern to the microbiologist community. Most procedures require several steps and amplification techniques. Carbohydrates are well-established receptors for host-pathogen interactions, which can be amplified using glycodendritic architectures on the basis of multivalent binding interactions. Given that uropathogenic Escherichia coli bacterial FimH is based on such mannopyranoside-binding interactions, we demonstrate herein that synthetic monomeric and trimeric thiolated α-d-mannosides can be effectively bound to gold substrate-functionalized self-assembled monolayers (SAMs) preactivated with maleimide functionalities. Mannosides grafted onto SAMs were followed using Quartz Crystal Microbalance with Dissipation (QCM-D). Binding recognition efficiency was first evaluated using the plant lectin from Canavalia ensiformis (ConA) also using QCM-D. We showed a direct correlation between the amount of mannoside bound and the lectin attachment. Even though there was less trimer bound (nM/cm2) to the surface, we observed a 7-fold higher amount of lectin anchoring, thus further demonstrating the value of the multivalent interactions. We next examined the relative fimbriated E. coli selective adhesion/capture to either the monomeric or the trimeric mannoside bound to the surface. Our results established the successful engineering of the surfaces to show E. coli adhesion via specific mannopyranoside binding but unexpectedly, the monomeric derivative was more efficient than the trimeric analog, which could be explained by steric hindrance. This approach strongly suggests that it could be broadly applicable to other Gram-negative bacteria sharing analogous carbohydrate-dependent binding interactions.


Assuntos
Escherichia coli Uropatogênica , Escherichia coli Uropatogênica/metabolismo , Manose/metabolismo , Manosídeos/química , Concanavalina A , Lectinas
12.
Catheter Cardiovasc Interv ; 100(6): 1067, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36444700
13.
J Chromatogr A ; 1677: 463292, 2022 Aug 16.
Artigo em Inglês | MEDLINE | ID: mdl-35853426

RESUMO

The ability to reversibly bind carbohydrates is an incredible property from lectins. Such characteristic has led these molecules to be employed in several applications involving medical research and biotechnology. Generally, these proteins follow several steps towards purification. Here, the synthesis, physical characterization, and use of levan-coated magnetite nanoparticles (MNPs-levan) for lectin isolation is described. Canavalia ensiformis and Cratylia mollis were used as sources of Concanavalin A and Cramoll, respectively, that were purified by using MNPs-levan. Mass spectrometry, SDS-PAGE, and hemagglutinating activity were employed to assess the efficiency of the process. Moreover, by using mass spectrometry approaches, a novel lectin, similar to Canavalin, was also identified for C. mollis, corroborating the advantages of using nanoparticles over microparticles. MNPs-levan could also be recycled, making this a low-cost, scalable process that can be efficiently employed over crude samples.


Assuntos
Fabaceae , Nanopartículas de Magnetita , Fabaceae/química , Óxido Ferroso-Férrico , Frutanos , Lectinas/análise , Lectinas/química , Extratos Vegetais/análise , Lectinas de Plantas/química , Plantas/metabolismo , Sementes/química
14.
Methods Mol Biol ; 2487: 189-195, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35687237

RESUMO

As the vast majority of enzymes are glycosylated, lectins can serve as molecular glues to agglutinate multiple glycoenzymes for preparing multienzyme catalysts in an efficient and biocompatible way. Taking glucose oxidase and horseradish peroxidase as a model cascade, we describe in this protocol the coimmobilization of cascade glycoenzymes through lectin-mediated protein agglutination with and without magnetic nanoparticles as carriers.


Assuntos
Enzimas Imobilizadas , Lectinas , Concanavalina A , Enzimas Imobilizadas/metabolismo , Glucose Oxidase/metabolismo , Peroxidase do Rábano Silvestre , Lectinas/metabolismo
15.
Catheter Cardiovasc Interv ; 100(2): 219-224, 2022 08.
Artigo em Inglês | MEDLINE | ID: mdl-35652162

RESUMO

OBJECTIVES: Determine the true incidence and time course of atrial fibrillation (AF) after patent foramen ovale closure (PFOc) using implantable loop recorders (ILR) placed during cryptogenic stroke evaluation. BACKGROUND: Published trials report a 2%-6.6% incidence of postimplant atrial fibrillation (PIAF) after PFOc, which is probably a gross underestimation, as only patients presenting in AF were captured. Episodes of paroxysmal and silent AF would have been missed. METHODS: Of 761 patients who underwent PFOc at a single center between January 2016 and December 2020, 35 patients had an ILR implanted before PFOc, without documentation of AF, and had ≥1 month of monitoring post-PFOc. The incidence, onset, and conclusion of AF episodes were determined from a review of patient records. RESULTS: The mean duration of ILR monitoring was 54.6 ± 39.4 weeks after PFOc. AF occurred in 13/35 (37%) patients. PFOc patients who developed PIAF were older than those who did not (62 ± 11 vs. 52 ± 14 years, p = 0.03). In 12/13, the initial PIAF event occurred within 4 weeks of PFOc, with the greatest frequency around 2 weeks and conclusion by 12 weeks in all. No recurrent strokes occurred during ILR monitoring. CONCLUSION: The actual incidence of PIAF was far greater than previously reported and was significantly associated with older age at PFOc. The timing of PIAF onset and termination were consistent with a postimplant inflammatory mechanism. The higher actual PIAF incidence underscores its low stroke potential in this population. A larger prospective trial is required to validate these preliminary results.


Assuntos
Fibrilação Atrial , Forame Oval Patente , Acidente Vascular Cerebral , Fibrilação Atrial/diagnóstico , Fibrilação Atrial/epidemiologia , Fibrilação Atrial/terapia , Forame Oval Patente/complicações , Forame Oval Patente/diagnóstico por imagem , Forame Oval Patente/epidemiologia , Humanos , Incidência , Estudos Prospectivos , Acidente Vascular Cerebral/diagnóstico , Acidente Vascular Cerebral/epidemiologia , Acidente Vascular Cerebral/etiologia , Resultado do Tratamento
16.
Cell Immunol ; 375: 104517, 2022 05.
Artigo em Inglês | MEDLINE | ID: mdl-35398604

RESUMO

A recent study revealed that d-mannose suppressed immunopathology in mouse models of autoimmune diabetes and airway inflammation and increased the proportion of regulatory T cells (Tregs) in mice. We investigated the effect of d-mannose on liver injury in murine autoimmune hepatitis (AIH) models induced by concanavalin A (ConA) and α-galactosylceramide (GalCer). Mouse models of AIH were created by intraperitoneal injection of GalCer or intravenous injection of ConA. Drinking water was supplemented with d-mannose and biochemically and pathologically examined over time. The administration of d-mannose to AIH model mice significantly reduced liver injury and reduced inflammatory cytokine expression. In addition, Tregs among splenocytes and intrahepatic lymphocytes were significantly increased by the administration of d-mannose. These results indicate that treatment with d-mannose reduced the inflammatory response in the liver and suppressed liver damage by increasing Tregs.


Assuntos
Hepatite Autoimune , Animais , Concanavalina A , Modelos Animais de Doenças , Fígado , Manose/metabolismo , Camundongos , Linfócitos T Reguladores
17.
Biotechnol Bioeng ; 119(7): 1781-1791, 2022 07.
Artigo em Inglês | MEDLINE | ID: mdl-35394653

RESUMO

Concanavalin A (ConA), a mannose (Man)-specific leguminous lectin isolated from the jack bean (Canavalia ensiformis) seed extracts, was discovered over a century ago. Although ConA has been extensively applied in various life science research, recombinant mature ConA expression has not been fully established. Here, we aimed to produce recombinant ConA (rConA) in lettuce (Lactuca sativa) using an Agrobacterium tumefaciens-mediated transient expression system. rConA could be produced as a fully active form from soluble fractions of lettuce leaves and purified by affinity chromatography. From 12 g wet weight of lettuce leaves, 0.9 mg rConA could be purified. The glycan-binding properties of rConA were then compared with that of the native ConA isolated from jack bean using glycoconjugate microarray and frontal affinity chromatography. rConA demonstrated a glycan-binding specificity similar to nConA. Both molecules bound to N-glycans containing a terminal Man residue. Consistent with previous reports, terminal Manα1-6Man was found to be an essential unit for the high-affinity binding of rConA and nConA, while bisecting GlcNAc diminished the binding of rConA and nConA to Manα1-6Man-terminated N-glycans. These results demonstrate that the fully active rConA could be produced using the A. tumefaciens-mediated transient expression system and used as a recombinant substitute for nConA.


Assuntos
Lactuca , Polissacarídeos , Cromatografia de Afinidade , Concanavalina A/metabolismo , Humanos , Lactuca/genética , Lactuca/metabolismo , Folhas de Planta/metabolismo , Polissacarídeos/metabolismo
18.
Catheter Cardiovasc Interv ; 99(5): 1538-1544, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35266270

RESUMO

OBJECTIVES: To assess the short- and long-term outcomes of balloon pulmonary valvuloplasty (BPV) in children with Noonan syndrome (NS). BACKGROUND: Pulmonary stenosis (PS) is the most common congenital heart lesion in NS. BPV is the accepted first line treatment in PS. However, BPV in NS patients has been reported to be less effective, without specific factors for the need for reintervention being identified. METHODS: Retrospective case-note review of all patients with NS who underwent BPV between 1985 and 2020. Patients were divided into 2 groups: those with supravalvular pulmonary stenosis (SPS) in addition to valvar PS, and those with isolated valvar PS. RESULTS: A cohort of 54 patients with NS underwent BPV at a median of 275 (interquartile range [IQR]: 108-575) days of age. SPS was present in 32 (59%) patients whereas 22 had (41) isolated PS. The preprocedural invasive gradient was 47 (IQR: 35-69) mmHg, and 44 (IQR: 35-48) mmHg in those with SPS and those without respectively (p = 0.88). Reintervention was required in 22 patients (41%): 17 (77%) with SPS and 5 (23%) without (p = 0.017). Fourteen patients (11 with SPS) required surgical reintervention and 8 (6 with SPS) required further BPV. There was no significant difference in the age at initial BPV, pre- and postprocedural gradients and interval until reintervention between groups. CONCLUSION: This is the largest reported cohort of patients with NS undergoing BPV. Although BPV is often successful, the reintervention rates are high. SPS was a risk factor for reintervention.


Assuntos
Síndrome de Noonan , Estenose da Valva Pulmonar , Valva Pulmonar , Criança , Humanos , Síndrome de Noonan/complicações , Síndrome de Noonan/diagnóstico , Valva Pulmonar/diagnóstico por imagem , Valva Pulmonar/cirurgia , Estenose da Valva Pulmonar/diagnóstico por imagem , Estenose da Valva Pulmonar/terapia , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento
19.
Pharmaceutics ; 15(1)2022 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-36678721

RESUMO

The extreme aggressiveness and lethality of many cancer types appeal to the problem of the development of new-generation treatment strategies based on smart materials with a mechanism of action that differs from standard treatment approaches. The targeted delivery of nanoparticles to specific cancer cell receptors is believed to be such a strategy; however, there are no targeted nano-drugs that have successfully completed clinical trials to date. To meet the challenge, we designed an alternative way to eliminate tumors in vivo. Here, we show for the first time that the targeting of lectin-equipped polymer nanoparticles to the glycosylation profile of cancer cells, followed by photodynamic therapy (PDT), is a promising strategy for the treatment of aggressive tumors. We synthesized polymer nanoparticles loaded with magnetite and a PDT agent, IR775 dye (mPLGA/IR775). The magnetite incorporation into the PLGA particle structure allows for the quantitative tracking of their accumulation in different organs and the performing of magnetic-assisted delivery, while IR775 makes fluorescent in vivo bioimaging as well as light-induced PDT possible, thus realizing the theranostics concept. To equip PLGA nanoparticles with targeting modality, the particles were conjugated with lectins of different origins, and the flow cytometry screening revealed that the most effective candidate for breast cancer cell labeling is ConA, a lectin from Canavalia ensiformis. In vivo experiments showed that after i.v. administration, mPLGA/IR775-ConA nanoparticles efficiently accumulated in the allograft tumors under the external magnetic field; produced a bright fluorescent signal for in vivo bioimaging; and led to 100% tumor growth inhibition after the single session of PDT, even for large solid tumors of more than 200 mm3 in BALB/c mice. The obtained results indicate that the mPLGA/IR775 nanostructure has great potential to become a highly effective oncotheranostic agent.

20.
Spectrochim Acta A Mol Biomol Spectrosc ; 267(Pt 1): 120494, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34689006

RESUMO

The anionic surfactant sodium dodecyl sulfate (SDS) is homologous to the cellular membrane lipids, and is known to stimulate amyloid fibrillation in several proteins. However, the mechanism by which SDS influences aggregation and structural changes in succinylated protein has not been determined. In this study, we observed the effects of variable SDS concentrations on succinyl-ConA aggregation at pH 3.5 and proposed a possible mechanism of SDS-induced succinyl-ConA aggregation. We used several biophysical techniques to identify the changes caused by SDS. Our results suggest that SDS stimulates succinyl-ConA aggregation in a concentration-dependent manner. From turbidity measurements, it was evident that a very low concentration (<0.1 mM) of SDS did not induce succinyl-ConA aggregation and proteins remained soluble. However, aggregations were observed at 0.1-2.5 mM SDS, which then dissipated at SDS concentrations above 2.5 mM. Far-UV CD results suggest that the ß-sheet secondary structure of succinyl-ConA transformed into the cross-ß-sheet structure in the presence of aggregating SDS concentrations. Notably, at SDS concentrations above 2.5 mM, the succinyl-ConA ß-sheet transformed into an α-helical structure. The SDS-induced succinyl-ConA amyloid-like aggregates were confirmed by transmission electron microscopy (TEM). We propose that SDS modulates amyloid fibrillation in succinyl-ConA due to electrostatic and hydrophobic interactions and succinylation affects SDS-induced succinyl-ConA aggregation.


Assuntos
Amiloide , Agregados Proteicos , Concanavalina A , Concentração de Íons de Hidrogênio , Dodecilsulfato de Sódio
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