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1.
J Biol Chem ; 299(8): 104889, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37286041

RESUMEN

Human neutrophil elastase (HNE) plays a pivotal role in innate immunity, inflammation, and tissue remodeling. Aberrant proteolytic activity of HNE contributes to organ destruction in various chronic inflammatory diseases including emphysema, asthma, and cystic fibrosis. Therefore, elastase inhibitors could alleviate the progression of these disorders. Here, we used the systematic evolution of ligands by exponential enrichment to develop ssDNA aptamers that specifically target HNE. We determined the specificity of the designed inhibitors and their inhibitory efficacy against HNE using biochemical and in vitro methods, including an assay of neutrophil activity. Our aptamers inhibit the elastinolytic activity of HNE with nanomolar potency and are highly specific for HNE and do not target other tested human proteases. As such, this study provides lead compounds suitable for the evaluation of their tissue-protective potential in animal models.


Asunto(s)
Aptámeros de Nucleótidos , Elastasa de Leucocito , Inhibidores de Serina Proteinasa , Humanos , Fibrosis Quística/tratamiento farmacológico , Enfisema/tratamiento farmacológico , Elastasa de Leucocito/antagonistas & inhibidores , Neutrófilos/efectos de los fármacos , Inhibidores de Serina Proteinasa/síntesis química , Inhibidores de Serina Proteinasa/farmacología , Inhibidores de Serina Proteinasa/uso terapéutico , Aptámeros de Nucleótidos/síntesis química , Aptámeros de Nucleótidos/farmacología , Aptámeros de Nucleótidos/uso terapéutico , Sensibilidad y Especificidad , Activación Enzimática/efectos de los fármacos , Proteolisis/efectos de los fármacos , Células Cultivadas
2.
J Immunol ; 209(7): 1348-1358, 2022 10 01.
Artículo en Inglés | MEDLINE | ID: mdl-36165203

RESUMEN

Endotoxin tolerance is a state of hyporesponsiveness to LPS, triggered by previous exposure to endotoxin. Such an immunosuppressive state enhances the risks of secondary infection and has been associated with the pathophysiology of sepsis. Although this phenomenon has been extensively studied, its molecular mechanism is not fully explained. Among candidates that play a crucial role in this process are negative regulators of TLR signaling, but the contribution of MCP-induced protein 1 (MCPIP1; Regnase-1) has not been studied yet. To examine whether macrophage expression of MCPIP1 participates in endotoxin tolerance, we used both murine and human primary macrophages devoid of MCPIP1 expression. In our study, we demonstrated that MCPIP1 contributes to LPS hyporesponsiveness induced by subsequent LPS stimulation and macrophage reprogramming. We proved that this mechanism revolves around the deubiquitinase activity of MCPIP1, which inhibits the phosphorylation of MAPK and NF-κB activation. Moreover, we showed that MCPIP1 controlled the level of proinflammatory transcripts in LPS-tolerized cells independently of its RNase activity. Finally, we confirmed these findings applying an in vivo endotoxin tolerance model in wild-type and myeloid MCPIP1-deficient mice. Taken together, this study describes for the first time, to our knowledge, that myeloid MCPIP1 participates in endotoxin tolerance and broadens the scope of known negative regulators of the TLR4 pathway crucial in this phenomenon.


Asunto(s)
Lipopolisacáridos , Receptor Toll-Like 4 , Animales , Enzimas Desubicuitinizantes , Endorribonucleasas , Tolerancia a Endotoxinas , Endotoxinas , Humanos , Lipopolisacáridos/farmacología , Macrófagos/metabolismo , Ratones , Ratones Endogámicos C57BL , FN-kappa B/metabolismo , Ribonucleasas/genética , Receptor Toll-Like 4/metabolismo , Factores de Transcripción
3.
BMC Med Educ ; 22(1): 190, 2022 Mar 18.
Artículo en Inglés | MEDLINE | ID: mdl-35303864

RESUMEN

BACKGROUND: In addition to vocational education and experience, the pharmaceutical profession's proper pursuit requires acquiring and continuously improving professional competencies. In recent years, the need has been increasingly highlighted for developing a medical education system based on helping students develop their competencies. It is necessary to adapt the tools and methods for assessing competencies during formal education. It will enable students to know the directions of further personal or professional development. OBJECTIVE: The study aimed to compare pharmacy students' self-assessment outcomes before and after the Objective Structured Practical Examination (OSPE), which finished the Pharmaceutical Care course (PCc). The study's purpose was also to compare the outcomes of the self-assessment of competencies between the students of two academic years for whom classes on the PCc were provided by different methods. METHODS: The study was conducted over two academic years (2018/2019 and 2019/2020) among 5th-year students enrolled at the Faculty of Pharmacy of the Jagiellonian University Medical College (JUMC) at the end of the Pharmaceutical Care course. Different teaching methods were used in the delivery of the course in these academic years. The students self-assessed their competencies using a questionnaire consisting of a list of personal and patient care competencies. The students completed the questionnaire before and after the OSPE, which followed the completion of the PCc. RESULTS: Students' professional competencies as self-assessed after the exam were higher than those assessed before the exam. Differences were observed in both personal and patient care competencies. Students taking the course in the 2019/2020 academic year set their pre-OSPE competencies higher than students taking the PCc in 2018/2019. CONCLUSION: The self-assessment scores increased for most competencies included in the study following the OSPE. This may suggest that taking part in the exam, involvement in patient's case simulations, and self-assessment of performance at individual stages of the exam contributed to increased subjective assessment of professional competencies.


Asunto(s)
Estudiantes de Farmacia , Evaluación Educacional/métodos , Humanos , Farmacéuticos , Competencia Profesional , Autoevaluación (Psicología)
4.
Int J Mol Sci ; 22(13)2021 Jun 22.
Artículo en Inglés | MEDLINE | ID: mdl-34206444

RESUMEN

The alarming raise of multi-drug resistance among human microbial pathogens makes the development of novel therapeutics a priority task. In contrast to conventional antibiotics, antimicrobial peptides (AMPs), besides evoking a broad spectrum of activity against microorganisms, could offer additional benefits, such as the ability to neutralize toxins, modulate inflammatory response, eradicate bacterial and fungal biofilms or prevent their development. The latter properties are of special interest, as most antibiotics available on the market have limited ability to diffuse through rigid structures of biofilms. Lipidation of AMPs is considered as an effective approach for enhancement of their antimicrobial potential and in vivo stability; however, it could also have undesired impact on selectivity, solubility or the aggregation state of the modified peptides. In the present work, we describe the results of structural modifications of compounds designed based on cationic antimicrobial peptides DK5 and CAR-PEG-DK5, derivatized at their N-terminal part with fatty acids with different lengths of carbon chain. The proposed modifications substantially improved antimicrobial properties of the final compounds and their effectiveness in inhibition of biofilm development as well as eradication of pre-formed 24 h old biofilms of Candida albicans and Staphylococcus aureus. The most active compounds (C5-DK5, C12-DK5 and C12-CAR-PEG-DK5) were also potent against multi-drug resistant Staphylococcus aureus USA300 strain and clinical isolates of Pseudomonas aeruginosa. Both experimental and in silico methods revealed strong correlation between the length of fatty acid attached to the peptides and their final membranolytic properties, tendency to self-assemble and cytotoxicity.


Asunto(s)
Péptidos Catiónicos Antimicrobianos/química , Péptidos Catiónicos Antimicrobianos/farmacología , Antiinfecciosos/farmacología , Bacterias/efectos de los fármacos , Farmacorresistencia Microbiana/efectos de los fármacos , Estabilidad de Medicamentos , Humanos , Pruebas de Sensibilidad Microbiana , Estructura Molecular , Análisis Espectral , Relación Estructura-Actividad , Termodinámica
5.
Int J Mol Sci ; 21(23)2020 Nov 30.
Artículo en Inglés | MEDLINE | ID: mdl-33266231

RESUMEN

LL-37, the only member of the mammalian cathelicidin in humans, plays an essential role in innate immunity by killing pathogens and regulating the inflammatory response. However, at an inflammatory focus, arginine residues in LL-37 can be converted to citrulline via a reaction catalyzed by peptidyl-arginine deiminases (PAD2 and PAD4), which are expressed in neutrophils and are highly active during the formation of neutrophil extracellular traps (NETs). Citrullination impairs the bactericidal activity of LL-37 and abrogates its immunomodulatory functions. Therefore, we hypothesized that citrullination-resistant LL-37 variants would retain the functionality of the native peptide in the presence of PADs. To test this hypothesis, we synthetized LL-37 in which arginine residues were substituted by homoarginine (hArg-LL-37). Bactericidal activity of hArg-LL-37 was comparable with that of native LL-37, but neither treatment with PAD4 nor exposure to NETs affected the antibacterial and immunomodulatory activities of hArg-LL-37. Importantly, the susceptibilities of LL-37 and hArg-LL-37 to degradation by proteases did not significantly differ. Collectively, we demonstrated that citrullination-resistant hArg-LL-37 is an attractive lead compound for the generation of new agents to treat bacterial infections and other inflammatory diseases associated with enhanced PAD activity. Moreover, our results provide a proof-of-concept for synthesis of therapeutic peptides using homoarginine.


Asunto(s)
Antiinfecciosos/farmacología , Péptidos Catiónicos Antimicrobianos/farmacología , Hidrolasas/metabolismo , Secuencia de Aminoácidos , Animales , Antiinfecciosos/química , Péptidos Catiónicos Antimicrobianos/química , Supervivencia Celular/efectos de los fármacos , Cromatografía Líquida de Alta Presión , Citrulinación/efectos de los fármacos , Citocinas/metabolismo , Activación Enzimática , Humanos , Factores Inmunológicos/química , Factores Inmunológicos/farmacología , Macrófagos/inmunología , Macrófagos/metabolismo , Ratones , Pruebas de Sensibilidad Microbiana , Arginina Deiminasa Proteína-Tipo 4/genética , Arginina Deiminasa Proteína-Tipo 4/aislamiento & purificación , Proteolisis , Células RAW 264.7 , Catelicidinas
6.
Int J Mol Sci ; 20(19)2019 Sep 25.
Artículo en Inglés | MEDLINE | ID: mdl-31557917

RESUMEN

Staphylococcus aureus is a major infectious agent responsible for a plethora of superficial skin infections and systemic diseases, including endocarditis and septic arthritis. Recent epidemiological data revealed the emergence of resistance to commonly used antibiotics, including increased numbers of both hospital- and community-acquired methicillin-resistant S. aureus (MRSA). Due to their potent antimicrobial functions, low potential to develop resistance, and immunogenicity, antimicrobial peptides (AMPs) are a promising alternative treatment for multidrug-resistant strains. Here, we examined the activity of a lysine-rich derivative of amphibian temporin-1CEb (DK5) conjugated to peptides that exert pro-proliferative and/or cytoprotective activity. Analysis of a library of synthetic peptides to identify those with antibacterial potential revealed that the most potent agent against multidrug-resistant S. aureus was a conjugate of a temporin analogue with the synthetic Leu-enkephalin analogue dalargin (DAL). DAL-PEG-DK5 exerted direct bactericidal effects via bacterial membrane disruption, leading to eradication of both planktonic and biofilm-associated staphylococci. Finally, we showed that accumulation of the peptide in the cytoplasm of human keratinocytes led to a marked clearance of intracellular MRSA, resulting in cytoprotection against invading bacteria. Collectively, the data showed that DAL-PEG-DK5 might be a potent antimicrobial agent for treatment of staphylococcal skin infections.


Asunto(s)
Antiinfecciosos/farmacología , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Proteínas/farmacología , Péptidos Catiónicos Antimicrobianos , Humanos , Pruebas de Sensibilidad Microbiana , Viabilidad Microbiana/efectos de los fármacos , Proteínas/química , Infecciones Estafilocócicas/tratamiento farmacológico , Infecciones Estafilocócicas/microbiología , Staphylococcus epidermidis/efectos de los fármacos
7.
Antimicrob Agents Chemother ; 60(4): 1955-66, 2016 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-26729490

RESUMEN

Novel sulfonated derivatives of poly(allylamine hydrochloride) (NSPAHs) and N-sulfonated chitosan (NSCH) have been synthesized, and their activity against influenza A and B viruses has been studied and compared with that of a series of carrageenans, marine polysaccharides of well-documented anti-influenza activity. NSPAHs were found to be nontoxic and very soluble in water, in contrast to gel-forming and thus generally poorly soluble carrageenans.In vitroandex vivostudies using susceptible cells (Madin-Darby canine kidney epithelial cells and fully differentiated human airway epithelial cultures) demonstrated the antiviral effectiveness of NSPAHs. The activity of NSPAHs was proportional to the molecular mass of the chain and the degree of substitution of amino groups with sulfonate groups. Mechanistic studies showed that the NSPAHs and carrageenans inhibit influenza A and B virus assembly in the cell.


Asunto(s)
Antivirales/farmacología , Quitosano/farmacología , Subtipo H1N1 del Virus de la Influenza A/efectos de los fármacos , Subtipo H3N2 del Virus de la Influenza A/efectos de los fármacos , Virus de la Influenza B/efectos de los fármacos , Poliaminas/farmacología , Polímeros/farmacología , Ésteres del Ácido Sulfúrico/farmacología , Animales , Antivirales/síntesis química , Quitosano/síntesis química , Perros , Células Epiteliales/efectos de los fármacos , Células Epiteliales/virología , Humanos , Subtipo H1N1 del Virus de la Influenza A/genética , Subtipo H1N1 del Virus de la Influenza A/crecimiento & desarrollo , Subtipo H3N2 del Virus de la Influenza A/genética , Subtipo H3N2 del Virus de la Influenza A/crecimiento & desarrollo , Virus de la Influenza B/genética , Virus de la Influenza B/crecimiento & desarrollo , Concentración 50 Inhibidora , Células de Riñón Canino Madin Darby , Poliaminas/síntesis química , Polielectrolitos , Polímeros/síntesis química , ARN Viral/antagonistas & inhibidores , ARN Viral/biosíntesis , Relación Estructura-Actividad , Ésteres del Ácido Sulfúrico/síntesis química , Ensamble de Virus/efectos de los fármacos , Acoplamiento Viral/efectos de los fármacos , Inactivación de Virus/efectos de los fármacos , Internalización del Virus/efectos de los fármacos , Replicación Viral/efectos de los fármacos
8.
J Virol ; 89(14): 7202-13, 2015 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-25926653

RESUMEN

UNLABELLED: Human coronavirus (hCoV) HKU1 is one of six hCoVs identified to date and the only one with an unidentified cellular receptor. hCoV-HKU1 encodes a hemagglutinin-esterase (HE) protein that is unique to the group a betacoronaviruses (group 2a). The function of HKU1-HE remains largely undetermined. In this study, we examined binding of the S1 domain of hCoV-HKU1 spike to a panel of cells and found that the S1 could specifically bind on the cell surface of a human rhabdomyosarcoma cell line, RD. Pretreatment of RD cells with neuraminidase (NA) and trypsin greatly reduced the binding, suggesting that the binding was mediated by sialic acids on glycoproteins. However, unlike other group 2a CoVs, e.g., hCoV-OC43, for which 9-O-acetylated sialic acid (9-O-Ac-Sia) serves as a receptor determinant, HKU1-S1 bound with neither 9-O-Ac-Sia-containing glycoprotein(s) nor rat and mouse erythrocytes. Nonetheless, the HKU1-HE was similar to OC43-HE, also possessed sialate-O-acetylesterase activity, and acted as a receptor-destroying enzyme (RDE) capable of eliminating the binding of HKU1-S1 to RD cells, whereas the O-acetylesterase-inactive HKU1-HE mutant lost this capacity. Using primary human ciliated airway epithelial (HAE) cell cultures, the only in vitro replication model for hCoV-HKU1 infection, we confirmed that pretreatment of HAE cells with HE but not the enzymatically inactive mutant blocked hCoV-HKU1 infection. These results demonstrate that hCoV-HKU1 exploits O-Ac-Sia as a cellular attachment receptor determinant to initiate the infection of host cells and that its HE protein possesses the corresponding sialate-O-acetylesterase RDE activity. IMPORTANCE: Human coronaviruses (hCoV) are important human respiratory pathogens. Among the six hCoVs identified to date, only hCoV-HKU1 has no defined cellular receptor. It is also unclear whether hemagglutinin-esterase (HE) protein plays a role in viral entry. In this study, we found that, similarly to other members of the group 2a CoVs, sialic acid moieties on glycoproteins are critical receptor determinants for the hCoV-HKU1 infection. Interestingly, the virus seems to employ a type of sialic acid different from those employed by other group 2a CoVs. In addition, we determined that the HKU1-HE protein is an O-acetylesterase and acts as a receptor-destroying enzyme (RDE) for hCoV-HKU1. This is the first study to demonstrate that hCoV-HKU1 uses certain types of O-acetylated sialic acid residues on glycoproteins to initiate the infection of host cells and that the HKU1-HE protein possesses sialate-O-acetylesterase RDE activity.


Asunto(s)
Coronavirus/fisiología , Hemaglutininas Virales/metabolismo , Ácido N-Acetilneuramínico/metabolismo , Receptores Virales/análisis , Glicoproteína de la Espiga del Coronavirus/metabolismo , Proteínas Virales de Fusión/metabolismo , Acoplamiento Viral , Células Cultivadas , Coronavirus/enzimología , Humanos
9.
FEBS Open Bio ; 14(3): 498-504, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38308430

RESUMEN

Periodontal disease is one of the most common forms of inflammation. It is currently diagnosed by observing symptoms such as gingival bleeding and attachment loss. However, the detection of biomarkers that precede such symptoms would allow earlier diagnosis and prevention. Aptamers are short oligonucleotides or peptides that fold into three-dimensional conformations conferring the ability to bind molecular targets with high affinity and specificity. Here we report the selection of aptamers that bind specifically to the bacterium Tannerella forsythia, a pathogen frequently associated with periodontal disease. Two aptamers with the highest affinity were examined in more detail, revealing that their binding is probably dependent on mirolysin, a surface-associated protease secreted by the T. forsythia type-9 secretion system. The aptamers showed minimal cross-reactivity to other periodontopathogens and are therefore promising leads for the development of new tools to study the composition of the periodontitis-associated dysbiotic bacteriome as well as inexpensive new diagnostic assays.


Asunto(s)
Periodontitis , Tannerella forsythia , Humanos , Periodontitis/diagnóstico , Periodontitis/microbiología , Inflamación , Péptido Hidrolasas , Oligonucleótidos
10.
J Oral Microbiol ; 16(1): 2292382, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38456121

RESUMEN

Background: Three-dimensional (3D) tissue models bridge the gap between conventional two-dimensional cell cultures and animal models. The aim of this study was to develop an organotypic 3D gingival (OTG) model to provide a tool to investigate bacterial and viral pathogens in periodontitis. Methods: The OTG model composed of gingival fibroblasts (GFs) and telomerase-immortalized gingival keratinocytes (TIGKs) was constructed and applied to study infections by Porphyromonas gingivalis and herpes simplex virus 1 (HSV-1). Immunohistochemical staining, confocal microscopy, qPCR, titration techniques, and colony-forming unit counts were applied to interrogate epithelial markers expression, monitor P. gingivalis and HSV-1 presence, and evaluate the immune response along with the efficiency of antimicrobial drugs. Results: The OTG model resembled the morphology of the human gingiva. During infection, both pathogens penetrated deep into the tissue and persisted for a few days with P. gingivalis also forming a biofilm on the cell surface. The infection triggered the expression of inflammatory mediators in cells and both pathogens were efficiently eliminated by specific antimicrobials. Conclusions: Presented OTG model constitutes a simple and convenient tool to study the interaction between bacterial and viral pathogens within the gingival tissue, including penetration, persistence and biofilm formation. It is also suitable to examine the efficiency of antimicrobial drugs.

11.
Talanta ; 273: 125881, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38492283

RESUMEN

This work describes fabrication of gold electrodes modified with peptide conjugate DAL-PEG-DK5-PEG-OH that enables ultra-sensitive detection of lipopolysaccharide (LPS) isolated from the reference strain of Escherichia coli O26:B6. The initial step of the established procedure implies immobilization of the fully protected DAL-PEG-DK5-PEG-OH peptide on the surface of the gold electrode previously modified by cysteamine. Then side chain- and Fmoc-deprotection was performed in situ on the electrode surface, followed by its incubation in 1 % of BSA solution to block non-specific bindings sites before LPS detection. The efficiency of the modification was confirmed by X-ray Photoelectron Spectroscopy (XPS) measurements. Additionally, the cyclic voltammetry (CV) and electrochemical impendance spectroscopy (EIS) were employed to monitor the effectiveness of each step of the modification. The obtained results confirmed that the presence of the surface-attached covalently bound peptide DAL-PEG-DK5-PEG-OH enables LPS detection by means of CV technique within the range from 5 × 10-13 to 5 × 10-4 g/mL in PBS solution. The established limit of detection (LOD) for EIS measurements was 4.93 × 10-21 g/mL with wide linear detection range from 5 × 10-21 to 5 × 10-14 g/mL in PBS solution. Furthermore, we confirmed the ability of the electrode to detect LPS in a complex biological samples, like mouse urine and human serum. The effectiveness of the electrodes in identifying LPS in both urine and serum matrices was confirmed for samples containing LPS at both 2.5 × 10-15 g/mL and 2.5 × 10-9 g/mL.


Asunto(s)
Técnicas Biosensibles , Lipopolisacáridos , Animales , Ratones , Humanos , Oro/química , Péptidos Antimicrobianos , Endotoxinas , Electrodos , Péptidos , Técnicas Electroquímicas/métodos , Técnicas Biosensibles/métodos
12.
Pharmaceuticals (Basel) ; 15(6)2022 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-35745616

RESUMEN

Immune checkpoint targeting immunotherapy has revolutionized the treatment of certain cancers in the recent years. Determination of the status of immune checkpoint expression in particular cancers may assist decision making. Here, we describe the development of a single-stranded aptamer-based molecular probe specifically recognizing human PD-L1. Target engaging aptamers are selected by iterative enrichment from a random ssDNA pool and the binding is characterized biochemically. Specificity and dose dependence is demonstrated in vitro in the cell culture using human kidney tumor cells (786-0), human melanoma cells (WM115 and WM266.4) and human glioblastoma LN18 cancer cells. The utility of the probe in vivo is demonstrated using two mouse tumor models, where we show that the probe exhibits excellent potential in imaging. We postulate that further development of the probe may allow universal imaging of different types of tumors depending on their PD-L1 status, which may find utility in cancer diagnosis.

13.
J Gen Virol ; 92(Pt 10): 2324-2332, 2011 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-21715599

RESUMEN

Relatively recently discovered, human metapneumovirus (HMPV) is a human pathogen with worldwide prevalence, accounting for a substantial percentage of respiratory tract diseases. Concurrent viral and bacterial infections enable intricate mechanisms of cooperation between pathogens, which complicate the symptoms and outcome of the disease. Such bilateral interactions are based on the modulation of bacterial growth on epithelium pathologically altered during viral illness and the modulation of immune responses, as well as the enhancement of virus replication by bacterial virulence factors. This study showed that proteases produced by Porphyromonas gingivalis, a Gram-negative bacterium implicated in the development of periodontitis, named gingipains, facilitated HMPV replication in LLC-MK2 cells and may contribute to HMPV pathogenicity in patients with periodontitis. Gingipains at low nanomolar concentrations enabled HMPV replication and allowed virus propagation in vitro. In contrast to previously published data for influenza virus, however, Staphylococcus aureus proteases and human neutrophil elastase did not affect virus replication.


Asunto(s)
Adhesinas Bacterianas/metabolismo , Cisteína Endopeptidasas/metabolismo , Metapneumovirus/patogenicidad , Interacciones Microbianas , Porphyromonas gingivalis/enzimología , Línea Celular , Cisteína-Endopeptidasas Gingipaínas , Humanos , Elastasa de Leucocito/metabolismo , Staphylococcus aureus/enzimología
14.
J Gen Virol ; 92(Pt 6): 1358-1368, 2011 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-21325482

RESUMEN

Understanding the mechanisms of augmented bacterial pathogenicity in post-viral infections is the first step in the development of an effective therapy. This study assessed the effect of human coronavirus NL63 (HCoV-NL63) on the adherence of bacterial pathogens associated with respiratory tract illnesses. It was shown that HCoV-NL63 infection resulted in an increased adherence of Streptococcus pneumoniae to virus-infected cell lines and fully differentiated primary human airway epithelium cultures. The enhanced binding of bacteria correlated with an increased expression level of the platelet-activating factor receptor (PAF-R), but detailed evaluation of the bacterium-PAF-R interaction revealed a limited relevance of this process.


Asunto(s)
Adhesión Bacteriana , Coronavirus Humano NL63/fisiología , Células Epiteliales/microbiología , Células Epiteliales/virología , Infecciones del Sistema Respiratorio/microbiología , Infecciones del Sistema Respiratorio/virología , Streptococcus/fisiología , Línea Celular , Células Cultivadas , Células Epiteliales/metabolismo , Expresión Génica , Humanos , Glicoproteínas de Membrana Plaquetaria/genética , Glicoproteínas de Membrana Plaquetaria/metabolismo , Receptores Acoplados a Proteínas G/genética , Receptores Acoplados a Proteínas G/metabolismo , Infecciones del Sistema Respiratorio/genética , Infecciones del Sistema Respiratorio/metabolismo
15.
Biol Chem ; 392(3): 263-74, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21194373

RESUMEN

Bradykinin-related vasoactive peptides (kinins) are important mediators of local and systemic inflammatory reactions. However, at local inflammatory foci, the production of kinins from proteinaceous precursors (kininogens) can be affected by reactive oxygen species released by phagocyte cells. One of the predominant oxidants at these places is hypochlorous acid which is formed from hydrogen peroxide and chloride ions by neutrophil myeloperoxidase. In this study, inactivation of human kininogens after oxidation with the myeloperoxidase-H2O2-chloride system was observed and analyzed by protein chemistry methods. The kinin release from oxidized kininogens by major kinin-producing enzymes, plasma and tissue kallikreins, proceed with a very low rate. This effect was assigned to apparent inability of kallikreins to process the kinin N-terminus owing to the conversion of the adjacent Met-361 residue to methionine sulfoxide. Additionally, the oxidized high-molecular mass kininogen lost its natural ability to bind plasma prekallikrein. This effect was assigned to the oxidation of Trp-569 residue within the prekallikrein-binding region which is subsequently destructed owing to cleavage of the peptide bond after that residue. One possible pathophysiological consequence of the described effects on kininogens could be the impairment of the normal assembly and triggering of the kinin-forming system on defense cell surfaces.


Asunto(s)
Inflamación/metabolismo , Quininógenos/metabolismo , Cininas/metabolismo , Precalicreína/metabolismo , Especies Reactivas de Oxígeno/metabolismo , Secuencia de Aminoácidos , Bradiquinina/metabolismo , Humanos , Metionina/análogos & derivados , Metionina/metabolismo , Datos de Secuencia Molecular , Peroxidasa/metabolismo , Fagocitos/metabolismo , Triptófano/metabolismo
16.
Biol Chem ; 391(7): 823-30, 2010 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-20624001

RESUMEN

The secretion of proteolytic enzymes by pathogenic microorganisms is one of the most successful strategies used by pathogens to colonize and infect the host organism. The extracellular microbial proteinases can seriously deregulate the homeostatic proteolytic cascades of the host, including the kinin-forming system, repeatedly reported to be activated during bacterial infection. The current study assigns a kinin-releasing activity to secreted proteinases of Candida spp. yeasts, the major fungal pathogens of humans. Of several Candida species studied, C. parapsilosis and C. albicans in their invasive filamentous forms are shown to produce proteinases which most effectively degrade proteinaceous kinin precursors, the kininogens. These enzymes, classified as aspartyl proteinases, have the highest kininogen-degrading activity at low pH (approx. 3.5), but the associated production of bradykinin-related peptides from a small fraction of kininogen molecules is optimal at neutral pH (6.5). The peptides effectively interact with cellular B2-type kinin receptors. Moreover, kinin-related peptides capable of interacting with inflammation-induced B1-type receptors are also formed, but with a reversed pH dependence. The presented variability of the potential extracellular kinin production by secreted aspartyl proteinases of Candida spp. is consistent with the known adaptability of these opportunistic pathogens to different niches in the host organism.


Asunto(s)
Candida/enzimología , Quininógenos/metabolismo , Péptido Hidrolasas/metabolismo , Candida/metabolismo , Humanos
17.
Integr Pharm Res Pract ; 9: 49-63, 2020.
Artículo en Inglés | MEDLINE | ID: mdl-32161716

RESUMEN

OBJECTIVE: The current article is aimed at identifying the best practice for counseling around depression in community and outpatient pharmacies, resulting in a draft guideline, proposing key steps and an algorithm for integration of community pharmacists into care for patients with depression. METHODS: A literature review was performed followed by a detailed analysis, for the purpose of creation a short draft document used as a basis for creation of a guideline for pharmaceutical care for patients with depression. The technological scheme PRISMA flow diagram was applied. The paper is based on current knowledge, taking into consideration already published articles, guidelines, and recommendations about pharmaceutical care for patients with depression, giving a basis for further studies. RESULTS: This paper includes two main sections: 1) depression - a short description of the main symptoms, risk factors and pharmacotherapy guidelines available in Bulgaria important for the purposes of ensuring qualitative community-based pharmaceutical care; and 2) the pharmacists' role in providing high-quality care - the main aspects of pharmaceutical care for patients with depression with specific examples. CONCLUSION: The involvement of pharmacists in supporting depressive patients is crucial taking into account the specific characteristics of the pharmacological treatment: delayed onset of clinical results, risks in case of sudden pharmacotherapy abruption without physician consultation, multiple adverse drug reactions and drug-drug, drug-food and drug-alcohol interactions, etc. The current article could also be used as an initial document for creating a methodological guideline for providing pharmaceutical care services for patients with depression.

18.
Plant Physiol Biochem ; 47(4): 237-42, 2009 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-19167902

RESUMEN

The pool of thiamine diphosphate (TDP), available for TDP-dependent enzymes involved in the major carbohydrate metabolic pathways, is controlled by two enzyme systems that act in the opposite directions. The thiamine pyrophosphokinase (TPK) activates thiamine into TDP and the numerous phosphatases perform the reverse two-step dephosphorylation of TDP to thiamine monophosphate (TMP) and then to free thiamine. Properties and a possible cooperation of those enzymes in higher plants have not been extensively studied. In this work, we characterize highly purified preparations of TPK and a TDP/TMP phosphatase isolated from 6-day Zea mays seedlings. TPK was the 29-kDa monomeric protein, with the optimal activity at pH 9.0, the K(m) values of 12.4microM and 4.7mM for thiamine and ATP, respectively, and the V(max) value of 360pmol TDPmin(-1)mg(-1) protein. The enzyme required magnesium ions, and the best phosphate donor was GTP. The purified phosphatase was the dimer of 24kDa subunits, showed the optimal activity at pH 5.0 and had a rather broad substrate specificity, although TDP, but not TMP, was one of the preferable substrates. The K(m) values for TDP and TMP were 36microM and 49microM, respectively, and the V(max) value for TDP was significantly higher than for TMP (164 versus 60nmolesmin(-1)mg(-1) protein). The total activities of TPK and TDP phosphatases were similarly decreased when the seedlings were grown under the illumination, suggesting a coordinated regulation of both enzymes to stabilize the pool of the essential coenzyme.


Asunto(s)
Monoéster Fosfórico Hidrolasas/aislamiento & purificación , Monoéster Fosfórico Hidrolasas/metabolismo , Plantones/enzimología , Tiamina Pirofosfoquinasa/aislamiento & purificación , Tiamina Pirofosfoquinasa/metabolismo , Tiamina Pirofosfato/metabolismo , Zea mays/enzimología
19.
Pharmacy (Basel) ; 7(3)2019 Jun 27.
Artículo en Inglés | MEDLINE | ID: mdl-31252513

RESUMEN

INTRODUCTION: The study objective was to assess the impact of pharmacist-led education on the patient's knowledge and skills on SBPM (self-blood pressure monitoring). METHODS: Patient knowledge was assessed using tests and patients' skills were based on a checklist (20 parameters) completed by the researcher based on the SBPM video records. Patients taking pressure measurements were filmed for 20 days and after 6 months. After the first 10 days, patients were educated about the correct SBPM procedure. Knowledge tests were repeated three times (before/after/6 months after education). RESULTS: All patients' knowledge and skills in the field of SBPM were improved after education. After the education, patients scored an average of 9 out of 10 points in the knowledge test (increasing an average of five points after education), six months later-an average increase of 7.36 points. Patient skills after training were rated at 17.4 out of 20 points on average (increase by an average of 5.14 points after education), six months later, there was an average of 16.23 points. CONCLUSIONS: The study showed an increase in patients' knowledge and skills in the field of SBPM after training.

20.
Int Immunopharmacol ; 8(2): 237-41, 2008 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-18182233

RESUMEN

The invasion of human host by pathogenic microorganisms is often associated with increased kinin production which may occur due to the action of pathogen secretory proteinases or the activation of host's surface-dependent kinin generation cascade, initiated by the adsorption of high molecular weight kininogen (HK) on the pathogen cells. In this work we characterize for the first time the binding of HK by Candida yeasts and analyze this adsorption in terms of intraspecific variation and a dependence on the fungal morphology. The apparent dissociation constants for this interaction were in the order of 10(- 7) M and the binding capacity increased in the order: Candida glabrata

Asunto(s)
Candida/metabolismo , Quininógeno de Alto Peso Molecular/metabolismo , Adsorción
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