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1.
PLoS One ; 19(4): e0302027, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38598489

RESUMO

BACKGROUND: Pneumocytis jirovecii infection in preterm newborns has recently been associated with neonatal respiratory distress syndrome and bronchopulmonary dysplasia. Changes in the bacterial microbiota of the airways have also been described in infants with bronchopulmonary dysplasia. However, until now there has been no information on the airway mycobiota in newborns. The purpose of this study was to describe the airway mycobiota in term and preterm newborns and its possible association with respiratory distress syndrome. METHODS: Twenty-six matched preterm newborns with and without respiratory distress syndrome were studied, as well as 13 term babies. The identification of the fungal microbiota was carried out using molecular procedures in aspirated nasal samples at birth. RESULTS: The ascomycota phylum was identified in 89.7% of newborns, while the basidiomycota phylum was found in 33.3%. Cladosporium was the predominant genus in both term and preterm infants 38.4% vs. 73% without statistical differences. Candida sake and Pneumocystis jirovecii were only found in preterm infants, suggesting a potential relationship with the risk of prematurity. CONCLUSIONS: This is the first report to describe the fungal microbiota of the airways in term and preterm infants with and without respiratory distress syndrome. Although no differences have been observed, the number of cases analyzed could be small to obtain conclusive results, and more studies are needed to understand the role of the fungal microbiota of the airways in neonatal respiratory pathology.


Assuntos
Displasia Broncopulmonar , Micobioma , Pneumocystis carinii , Síndrome do Desconforto Respiratório do Recém-Nascido , Lactente , Recém-Nascido , Humanos , Recém-Nascido Prematuro
2.
Eur J Intern Med ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38453571

RESUMO

BACKGROUND: Over the past two decades, several studies have been conducted that have tried to answer questions on management of patients with acute heart failure (AHF) in terms of diagnosis and treatment. Updated international clinical practice guidelines (CPGs) have endorsed the findings of these studies. The aim of this document was to adapt recommendations of existing guidelines to help internists make decisions about specific and complex scenarios related to AHF. METHODS: The adaptation procedure was to identify firstly unresolved clinical problems in patients with AHF in accordance with the PICO (Population, Intervention, Comparison and Outcomes) process, then conduct a critical assessment of existing CPGs and choose recommendations that are most applicable to these specific scenarios. RESULTS: Seven PICOs were identified and CPGs were assessed. There is no single test that can help clinicians in discriminating patients with acute dyspnoea, congestion or hypoxaemia. Performing of echocardiography and natriuretic peptide evaluation is recommended, and chest X-ray and lung ultrasound may be considered. Treatment strategies to manage arterial hypotension and low cardiac output include short-term continuous intravenous inotropic support, vasopressors, renal replacement therapy, and temporary mechanical circulatory support. The most updated recommendations on how to treat specific patients with AHF and certain comorbidities and for reducing post-discharge rehospitalization and mortality are provided. Overall, 51 recommendations were endorsed and the rationale for the selection is provided in the main text. CONCLUSION: Through the use of appropriate tailoring process methodology, this document provides a simple and updated guide for internists dealing with AHF patients.

3.
Commun Chem ; 7(1): 15, 2024 Jan 18.
Artigo em Inglês | MEDLINE | ID: mdl-38238420

RESUMO

The coronavirus disease 2019 (COVID-19) pandemic continues to represent a global public health issue. The viral main protease (Mpro) represents one of the most attractive targets for the development of antiviral drugs. Herein we report peptidyl nitroalkenes exhibiting enzyme inhibitory activity against Mpro (Ki: 1-10 µM) good anti-SARS-CoV-2 infection activity in the low micromolar range (EC50: 1-12 µM) without significant toxicity. Additional kinetic studies of compounds FGA145, FGA146 and FGA147 show that all three compounds inhibit cathepsin L, denoting a possible multitarget effect of these compounds in the antiviral activity. Structural analysis shows the binding mode of FGA146 and FGA147 to the active site of the protein. Furthermore, our results illustrate that peptidyl nitroalkenes are effective covalent reversible inhibitors of the Mpro and cathepsin L, and that inhibitors FGA145, FGA146 and FGA147 prevent infection against SARS-CoV-2.

4.
J Clin Med ; 12(17)2023 Aug 24.
Artigo em Inglês | MEDLINE | ID: mdl-37685572

RESUMO

In 2020, Spain ranked fourth among European countries with the highest excess mortality due to COVID-19 disease. This study evaluates the impact of the COVID-19 pandemic on non-COVID patients in a tertiary hospital during the second pandemic wave in Spain (22 June 2020-6 December 2020). Data from Virgen del Rocío University Hospital in Seville during that timeframe were compared with the data from the same period in the preceding two years (2018-2019). Between-group comparisons were performed using the Chi-squared test, Student's t-test, or Mann-Whitney U tests, as appropriate. A total of 63,137 non-COVID patients were included in this study. During the second pandemic wave, a 19% decrease was observed in the annual number of non-COVID admissions overall (18,260 vs. 22,439, p < 0.001), but a 10% increase in the proportion of emergency admissions (60.6% vs. 54.93%, p < 0.001), a higher severity level of patients (1.79 vs. 1.72, p < 0.001), a longer in-hospital stay (7.02 vs. 6.74 days, p < 0.001), a 26% increase in non-COVID mortality (4.9% vs. 3.9%, p < 0.001), and a 50% increase in global mortality (5.9 vs. 3.9, p < 0.001) were also observed. In terms of both medical and surgical diagnoses, a significant reduction in the number of admissions and an increase in in-hospital mortality were observed. These results demonstrate the significant impact of the pandemic on hospital care, similar to what was previously observed during the initial wave in the same hospital. Our findings emphasize the need to include non-COVID patients when assessing the broad impact of the pandemic on healthcare, beyond its direct effects on COVID-19 patients.

5.
Bioorg Med Chem ; 94: 117480, 2023 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-37774448

RESUMO

Galectins, a family of endogenous glycan-binding proteins, play crucial roles in a broad range of physiological and pathological processes. Galectin-1 (Gal-1), a proto-type member of this family, is overexpressed in several cancers and plays critical roles in tumor-immune escape, angiogenesis and metastasis. Thus, generation of high-affinity Gal-1 inhibitors emerges as an attractive therapeutic approach for a wide range of neoplastic conditions. Small-molecule carbohydrate inhibitors based on lactose (Lac) and N-acetyllactosamine (LacNAc) structures have been tested showing different results. In this study, we evaluated Lac- and LacNAc-based compounds with specific chemical modifications at key positions as Gal-1 ligands by competitive solid-phase assays (SPA) and isothermal titration calorimetry (ITC). Both assays showed excellent correlation, highlighting that lactosides bearing bulky aromatic groups at the anomeric carbon and sulfate groups at the O3' position exhibited the highest binding affinities. To dissect the atomistic determinants for preferential affinity of the different tested Gal-1 ligands, molecular docking simulations were conducted and PRODIGY-LIG structure-based method was employed to predict binding affinity in protein-ligand complexes. Notably, calculated binding free energies derived from the molecular docking were in accordance with experimental values determined by SPA and ITC, showing excellent correlation between theoretical and experimental approaches. Moreover, this analysis showed that 3'-O-sulfate groups interact with residues of the Gal-1 subsite B, mainly with Asn33, while the ester groups of the aromatic anomeric group interact with Gly69 and Thr70 at Gal-1 subsite E, extending deeper into the pocket, which could account for the enhanced binding affinity. This study contributes to the rational design of highly optimized Gal-1 inhibitors to be further studied in cancer models and other pathologic conditions.

6.
Int J Biol Macromol ; 242(Pt 1): 124724, 2023 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-37148949

RESUMO

Proteins belonging to the ING family regulate the transcriptional state of chromatin by recruiting remodeling complexes to sites with histone H3 trimethylated at Lysine 4 (H3K4me3). This modification is recognized by the Plant HomeoDomain (PHD) present at the C-terminal region of the five ING proteins. ING3 facilitates acetylation of histones H2A and H4 by the NuA4-Tip60 MYST histone acetyl transferase complex, and it has been proposed to be an oncoprotein. The crystal structure of the N-terminal domain of ING3 shows that it forms homodimers with an antiparallel coiled-coil fold. The crystal structure of the PHD is similar to those of its four homologs. These structures explain the possible deleterious effects of ING3 mutations detected in tumors. The PHD binds histone H3K4me3 with low-micromolar, and binds the non-methylated histone with a 54-fold reduced affinity. Our structure explains the impact of site directed mutagenesis experiments on histone recognition. These structural features could not be confirmed for the full-length protein as solubility was insufficient for structural studies, but the structure of its folded domains suggest a conserved structural organization for the ING proteins as homodimers and bivalent readers of the histone H3K4me3 mark.


Assuntos
Histonas , Proteínas Supressoras de Tumor , Histonas/metabolismo , Proteínas Supressoras de Tumor/genética , Proteínas Supressoras de Tumor/metabolismo , Proteínas de Homeodomínio/metabolismo , Cromatina , Ligação Proteica
7.
Am J Med ; 136(5): 432-437, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-36822259

RESUMO

Limited English proficiency (LEP) is defined as individuals in whom English is not the primary language and who have limited ability to read, speak, write, or understand the English language. Cardiovascular (CV) team members routinely encounter language barriers in their practice. These barriers have a significant impact on the quality of CV care that patients with LEP receive. Despite evidence demonstrating the negative association between language barriers and health disparities, the impact on CV care is insufficiently known. In addition, older adults with CV disease and LEP are facing increasing risk of adverse events when complex medical information is not optimally delivered. Overcoming language barriers in CV care will need a thoughtful approach. Although well recognized, the initial step will be to continue to highlight the importance of language needs identification and appropriate use of professional interpreter services. In parallel, a health system-level approach is essential that describes initiatives and key policies to ensure a high-level quality of care for a growing LEP population. This review aims to present the topic of LEP during the CV care of older adults, for continued awareness along with practical considerations for clinical use and directions for future research.


Assuntos
Proficiência Limitada em Inglês , Humanos , Idoso , Idioma , Barreiras de Comunicação
8.
Sci Rep ; 13(1): 1634, 2023 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-36717651

RESUMO

We assessed the impact of the first wave of COVID-19 pandemic on non-COVID hospital admissions, non-COVID mortality, factors associated with non-COVID mortality, and changes in the profile of non-COVID patients admitted to hospital. We used the Spanish Minimum Basic Data Set with diagnosis grouped according to the Diagnostic Related Groups. A total of 10,594 patients (3% COVID-19; 97% non-COVID) hospitalised during the first wave in 2020 (27-February/07-June) were compared with those hospitalised within the same dates of 2017-2019 (average annual admissions: 14,037). We found a decrease in non-COVID medical (22%) and surgical (33%) hospitalisations and a 25.7% increase in hospital mortality among non-COVID patients during the first pandemic wave compared to pre-pandemic years. During the officially declared sub-period of excess mortality in the area (17-March/20-April, in-hospital non-COVID mortality was even higher (58.7% higher than the pre-pandemic years). Non-COVID patients hospitalised during the first pandemic wave (compared to pre-pandemic years) were older, more frequently men, with longer hospital stay and increased disease severity. Hospitalisation during the first pandemic wave in 2020, compared to hospitalisation during the pre-pandemic years, was an independent risk factor for non-COVID mortality (HR 1.30, 95% CI 1.07-1.57, p = 0.008), reflecting the negative impact of the pandemic on hospitalised patients.


Assuntos
COVID-19 , Masculino , Humanos , COVID-19/epidemiologia , Pandemias , Pacientes Internados , Espanha/epidemiologia , Hospitalização , Mortalidade Hospitalar , Estudos Retrospectivos
9.
Clin Microbiol Infect ; 29(4): 539.e1-539.e7, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36371030

RESUMO

OBJECTIVES: In cystic fibrosis (CF), there is a predisposition to bronchial colonization by potentially pathogenic microorganisms, such as fungi. Our aims were to describe the dynamics of respiratory mycobiota in patients with CF and to evaluate the geographic, age and gender variability in its distribution. METHODS: Cohort study in which 45 patients with CF from four hospitals in three Spanish cities were followed up during a 1-year period, obtaining spontaneous sputum samples every 3 to 6 months. Fungal microbiota were characterized by Internal Transcribed Spacer sequencing and Pneumocystis jirovecii was identified by nested PCR in a total of 180 samples. RESULTS: The presence of fungi were detected in 119 (66.11%) of the 180 samples and in 44 (97.8%) of the 45 patients: 19 were positive and 1 negative throughout all follow-ups and the remaining 25 presented alternation between positive and negative results. A total of 16 different genera were identified, with Candida spp. (50/180, 27.78%) and Pneumocystis spp. (44/180, 24.44%) being the most prevalent ones. The distribution of fungal genera was different among the evaluated centres (p < 0.05), by age (non-adults aged 6-17 years vs. adults aged ≥18 years) (p < 0.05) and by gender (p < 0.05). DISCUSSION: A high prevalence of fungal respiratory microbiota in patients with CF was observed, whose dynamics are characterized by the existence of multiple cycles of clearance and colonization, reporting the existence of geographic, age and gender variability in the distribution of fungal genera in this disease.


Assuntos
Fibrose Cística , Micobioma , Humanos , Adolescente , Adulto , Fibrose Cística/complicações , Estudos de Coortes , Escarro/microbiologia , Brônquios
10.
Int J Mol Sci ; 23(5)2022 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-35269646

RESUMO

Human galectin-3 (hGal-3) is involved in a variety of biological processes and is implicated in wide range of diseases. As a result, targeting hGal-3 for clinical applications has become an intense area of research. As a step towards the development of novel hGal-3 inhibitors, we describe a study of the binding of two Se-containing hGal-3 inhibitors, specifically that of di(ß-D-galactopyranosyl)selenide (SeDG), in which two galactose rings are linked by one Se atom and a di(ß-D-galactopyranosyl)diselenide (DSeDG) analogue with a diseleno bond between the two sugar units. The binding affinities of these derivatives to hGal-3 were determined by 15N-1H HSQC NMR spectroscopy and fluorescence anisotropy titrations in solution, indicating a slight decrease in the strength of interaction for SeDG compared to thiodigalactoside (TDG), a well-known inhibitor of hGal-3, while DSeDG displayed a much weaker interaction strength. NMR and FA measurements showed that both seleno derivatives bind to the canonical S face site of hGal-3 and stack against the conserved W181 residue also confirmed by X-ray crystallography, revealing canonical properties of the interaction. The interaction with DSeDG revealed two distinct binding modes in the crystal structure which are in fast exchange on the NMR time scale in solution, explaining a weaker interaction with hGal-3 than SeDG. Using molecular dynamics simulations, we have found that energetic contributions to the binding enthalpies mainly differ in the electrostatic interactions and in polar solvation terms and are responsible for weaker binding of DSeDG compared to SeDG. Selenium-containing carbohydrate inhibitors of hGal-3 showing canonical binding modes offer the potential of becoming novel hydrolytically stable scaffolds for a new class of hGal-3 inhibitors.


Assuntos
Proteínas Sanguíneas/química , Galectina 3 , Galectinas/química , Cristalografia por Raios X , Galactose , Galectina 3/metabolismo , Galectinas/metabolismo , Humanos , Ligação Proteica
11.
Eur J Intern Med ; 96: 5-12, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34903446

RESUMO

BACKGROUND: Several trials have been conducted in the last decades that challenged the management of patients with acute pulmonary embolism (PE) in terms of diagnosis and treatment. Updated international clinical practice guidelines (CPGs) endorsed the evidence from these trials. The aim of this document was to adapt recommendations from existing CPGs to assist physicians in decision making concerning specific and complex scenarios related to acute PE. METHODS: The flow for the adaptation procedure was first the identification of unsolved clinical issues in patients with acute PE (PICOs), then critically appraise the existing CPGs and choose the recommendations, which are the most applicable to these specific and complex scenarios. RESULTS: Five PICOs were identified and CPGs appraisal was performed. Concerning diagnosis of PE when computed tomographic pulmonary angiography is not available/contraindicated and d-dimer is less specific, perfusion lung scan is the preferred option in the majority of clinical scenarios. For the treatment of PE when relevant clinical conditions like pregnancy or severe renal failure are present heparin is to be used. Poor evidence and low-level recommendations exist on the best bleeding prediction rule in patients treated for PE. The duration of anticoagulation needs to be tailored concerning the presence of predisposing factors for index PE and the consequent risk for recurrence. Finally, recommendations on the opportunity to screen for cancer and thrombophilia patients without recognized thrombosis risk factors for PE are reported. Overall, 35 recommendations were endorsed and the rationale for the selection is reported in the main text. CONCLUSION: By the use of proper methodology for the adaptation process, this document offers a simple and updated guide for practicing clinicians dealing with complex patients.


Assuntos
Embolia Pulmonar , Trombofilia , Angiografia por Tomografia Computadorizada , Feminino , Humanos , Pulmão , Gravidez , Embolia Pulmonar/diagnóstico por imagem , Embolia Pulmonar/terapia , Tomografia Computadorizada por Raios X
12.
Biomolecules ; 11(12)2021 12 09.
Artigo em Inglês | MEDLINE | ID: mdl-34944498

RESUMO

Galectins are multi-purpose effectors acting via interactions with distinct counterreceptors based on protein-glycan/protein recognition. These processes are emerging to involve several regions on the protein so that the availability of a detailed structural characterization of a full-length galectin is essential. We report here the first crystallographic information on the N-terminal extension of the carbohydrate recognition domain of rat galectin-5, which is precisely described as an N-tailed proto-type-like galectin. In the ligand-free protein, the three amino-acid stretch from Ser2 to Ser5 is revealed to form an extra ß-strand (F0), and the residues from Thr6 to Asn12 are part of a loop protruding from strands S1 and F0. In the ligand-bound structure, amino acids Ser2-Tyr10 switch position and are aligned to the edge of the ß-sandwich. Interestingly, the signal profile in our glycan array screening shows the sugar-binding site to preferentially accommodate the histo-blood-group B (type 2) tetrasaccharide and N-acetyllactosamine-based di- and oligomers. The crystal structures revealed the characteristically preformed structural organization around the central Trp77 of the CRD with involvement of the sequence signature's amino acids in binding. Ligand binding was also characterized calorimetrically. The presented data shows that the N-terminal extension can adopt an ordered structure and shapes the hypothesis that a ligand-induced shift in the equilibrium between flexible and ordered conformers potentially acts as a molecular switch, enabling new contacts in this region.


Assuntos
Galectinas/química , Galectinas/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Motivos de Aminoácidos , Animais , Sequência de Carboidratos , Cristalografia por Raios X , Galectinas/genética , Modelos Moleculares , Ligação Proteica , Domínios Proteicos , Multimerização Proteica , Estrutura Secundária de Proteína , Ratos , Espalhamento a Baixo Ângulo
13.
J Fungi (Basel) ; 7(10)2021 Oct 13.
Artigo em Inglês | MEDLINE | ID: mdl-34682277

RESUMO

A Pneumocystis jirovecii is one of the most important microorganisms that cause pneumonia in immunosupressed individuals. The guideline for treatment and prophylaxis of Pneumocystis pneumonia (PcP) is the use of a combination of sulfa drug-containing trimethroprim and sulfamethoxazole. In the absence of a reliable method to culture Pneumocystis, molecular techniques have been developed to detect mutations in the dihydropteroate synthase gene, the target of sulfa drugs, where mutations are related to sulfa resistance in other microorganisms. The presence of dihydropteroate synthase (DHPS) mutations has been described at codon 55 and 57 and found almost around the world. In the current work, we analyzed the most common methods to identify these mutations, their geographical distribution around the world, and their clinical implications. In addition, we describe new emerging DHPS mutations. Other aspects, such as the possibility of transmitting Pneumocystis mutated organisms between susceptible patients is also described, as well as a brief summary of approaches to study these mutations in a heterologous expression system.

14.
Molecules ; 26(14)2021 Jul 12.
Artigo em Inglês | MEDLINE | ID: mdl-34299501

RESUMO

Xyleborus sp beetles are types of ambrosia beetles invasive to the United States and recently also to Mexico. The beetle can carry a fungus responsible for the Laurel Wilt, a vascular lethal disease that can host over 300 tree species, including redbay and avocado. This problem has a great economic and environmental impact. Indeed, synthetic chemists have recently attempted to develop new neonicotinoids. This is also due to severe drug resistance to "classic" insecticides. In this research, a series of neonicotinoids analogs were synthesized, characterized, and evaluated against Xyleborus sp. Most of the target compounds showed good to excellent insecticidal activity. Generally, the cyclic compounds also showed better activity in comparison with open-chain compounds. Compounds R-13, 23, S-29, and 43 showed a mortality percent of up to 73% after 12 h of exposure. These results highlight the enantioenriched compounds with absolute R configuration. The docking results correlated with experimental data which showed both cation-π interactions in relation to the aromatic ring and hydrogen bonds between the search cavity 3C79 and the novel molecules. The results suggest that these sorts of interactions are responsible for high insecticidal activity.


Assuntos
Besouros/efeitos dos fármacos , Inseticidas/síntese química , Inseticidas/farmacologia , Neonicotinoides/síntese química , Neonicotinoides/farmacologia , Gorgulhos/efeitos dos fármacos , Ambrosia/parasitologia , Animais , Besouros/microbiologia , Ericaceae/parasitologia , Fungos/patogenicidade , Ligação de Hidrogênio/efeitos dos fármacos , Doenças das Plantas/microbiologia , Árvores/parasitologia , Gorgulhos/microbiologia
15.
Med Mycol ; 59(9): 849-854, 2021 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-33693837

RESUMO

We conducted a pilot study of patients with cystic fibrosis (CF) to assess intra-family transmission of P. jirovecii and compare it with data on other prevalent pathogens such as P. aeruginosa and S. pneumoniae, in which respiratory transmission has already been documented. Oral swab samples from 10 patients with CF and 15 household members were collected at baseline and 2 weeks later. P. aeruginosa and S. pneumoniae were assessed using standardized culture methods and PCR, and P. jirovecii was assessed using real and nested PCR, genotyping the positive samples by direct sequencing. P. aeruginosa cultures were positive for 7/10 (70%) of patients with CF at baseline and was identified by PCR in 8/10 (80%) of cases at baseline and 2 weeks later. S. pneumoniae cultures were negative for all patients, but the microorganism was identified by PCR in two cases. P. jirovecii was detected by real time and nested PCR in 5/10 (50%) of the patients at the two time points. In the household members, P. aeruginosa and P. jirovecii were identified in 7/15 (46.7%), and S. pneumoniae was identified in 8/15 (53,3%). The concordance of positive or negative pairs of patients with CF and their household members was 33.3% (5/15) for P. aeruginosa, 46.7% (7/15) for S. pneumonia and 93.3% (14/15) for P. jirovecii. The concordance for P. jirovecii genotypes among five pairs with available genotype was 100%. This study suggests for the first time the possible transmission of Pneumocystis in the home of patients with CF, indicating that patients and their household members are reservoirs and possible sources of infection. LAY SUMMARY: This study suggests for the first time the possible transmission of Pneumocystis in the family environment of patients with cystic fibrosis, indicating that patients and their household members are reservoirs and possible sources of this infection.


Assuntos
Fibrose Cística/complicações , Transmissão Vertical de Doenças Infecciosas , Infecções Pneumocócicas/transmissão , Pneumocystis carinii/isolamento & purificação , Pneumonia por Pneumocystis/transmissão , Infecções por Pseudomonas/transmissão , Pseudomonas aeruginosa/isolamento & purificação , Streptococcus pneumoniae/isolamento & purificação , Adolescente , Adulto , Criança , Características da Família , Feminino , Genótipo , Humanos , Masculino , Projetos Piloto , Pneumocystis carinii/genética , Reação em Cadeia da Polimerase/métodos , Pseudomonas aeruginosa/genética , Streptococcus pneumoniae/genética , Adulto Jovem
16.
iScience ; 24(1): 101919, 2021 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-33409472

RESUMO

The small 3-O-sulfated galactose head group of sulfatides, an abundant glycosphingolipid class, poses the (sphinx-like) riddle on involvement of glycan bridging by tissue lectins (sugar code). First, synthesis of head group derivatives for functionalization of amphiphilic dendrimers is performed. Aggregation of resulting (biomimetic) vesicles, alone or in combination with lactose, demonstrates bridging by a tissue lectin (galectin-4). Physiologically, this can stabilize glycolipid-rich microdomains (rafts) and associate sulfatide-rich regions with specific glycoproteins. Further testing documents importance of heterobivalency and linker length. Structurally, sulfatide recognition by galectin-8 is shown to involve sphingosine's OH group as substitute for the 3'-hydroxyl of glucose of lactose. These discoveries underscore functionality of this small determinant on biomembranes intracellularly and on the cell surface. Moreover, they provide a role model to examine counterreceptor capacity of more complex glycans of glycosphingolipids and to start their bottom-up glycotope surface programming.

17.
Chemistry ; 27(1): 316-325, 2021 Jan 04.
Artigo em Inglês | MEDLINE | ID: mdl-32955737

RESUMO

Functional pairing between cellular glycoconjugates and tissue lectins like galectins has wide (patho)physiological significance. Their study is facilitated by nonhydrolysable derivatives of the natural O-glycans, such as S- and Se-glycosides. The latter enable extensive analyses by specific 77 Se NMR spectroscopy, but still remain underexplored. By using the example of selenodigalactoside (SeDG) and the human galectin-1 and -3, we have evaluated diverse 77 Se NMR detection methods and propose selective 1 H,77 Se heteronuclear Hartmann-Hahn transfer for efficient use in competitive NMR screening against a selenoglycoside spy ligand. By fluorescence anisotropy, circular dichroism, and isothermal titration calorimetry (ITC), we show that the affinity and thermodynamics of SeDG binding by galectins are similar to thiodigalactoside (TDG) and N-acetyllactosamine (LacNAc), confirming that Se substitution has no major impact. ITC data in D2 O versus H2 O are similar for TDG and LacNAc binding by both galectins, but a solvent effect, indicating solvent rearrangement at the binding site, is hinted at for SeDG and clearly observed for LacNAc dimers with extended chain length.


Assuntos
Galectinas , Ressonância Magnética Nuclear Biomolecular , Polissacarídeos , Sítios de Ligação , Óxido de Deutério , Galectinas/metabolismo , Humanos , Isótopos , Ligantes , Polissacarídeos/metabolismo , Ligação Proteica , Selênio , Solventes
18.
Front Public Health ; 7: 292, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31681723

RESUMO

Objective: Pneumocystis pneumonia remains a major opportunistic infection in immunocompromised patients worldwide. Colonization with Pneumocystis jirovecii has recently gained attention as an important issue for understanding the complete cycle of human Pneumocystis infection. P. jirovecii Superoxide Dismutase (SOD) gene could be a molecular target with high clinical relevance, but the epidemiological information about SOD genotypes distribution is scarce. The aim of this work was to provide information about the prevalence of genotypes of Pneumocystis SOD among Spanish patients and to describe possible differences between colonized and Pneumocystis pneumonia patients. Methods: we developed a cross-sectional study analyzing broncho-alveolar lavage fluid samples from 30 Pneumocystis pneumonia patients, 30 colonized patients, and 20 controls using a nested PCR protocol designed to amplify the sodA gene of P. jirovecii. The diagnostic yield of SOD Nested PCR was evaluated against the routine practice of mtLSUrRNA Nested PCR, which is considered the gold standard. Results: SOD locus was amplified in 90% of Pneumocystis pneumonia patients, 10% of colonized patients, and none of controls. Genotype SOD1 was observed in 11 cases (52.4%) and genotype SOD2 in 10 cases (47.6%). Genotype SOD2 was observed only in Pneumocystis pneumonia patients while the genotype SOD1 was observed in both colonized and Pneumocystis pneumonia patients. Conclusions: This study provides epidemiological information about SOD genotypes distribution in Spain, showing a low genetic diversity and a predominant presence of genotype SOD1 in colonized patients. SOP Nested PCR was more sensitive and accurate assay in Pneumocystis pneumonia patients than in colonized individuals.

19.
Front Public Health ; 7: 275, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31637227

RESUMO

Objective: The information about the epidemiology of Pneumocystis pneumonia (PcP) in Europe is scarce, and in Spain there are only data nationwide on patients with HIV infection. This study has been carried out with the aim of knowing in our country the current epidemiological spectrum and the risk factors of PcP. Methods: Observational, descriptive transversal study that included all patients admitted in Spain with diagnosis upon discharge of PcP registered in the National Health System's Hospital Discharge Records Database of Spain, between 2008 and 2012. Results: Four thousand five hundred and fifty four cases of PcP were reported, 1,204 (26.4%) in HIV-negative patients. During the study period, mean annual incidence (cases per million) was 19.4, remaining globally stable, increasing from 4.4 to 6.3 in HIV-negative patients and decreasing from 15.5 to 13.4 among HIV-infected patients. Risk factors were identified in 85.5% of HIV-negative cases, the most frequent being hematological neoplams (29%), chronic lung diseases (15.9%), and non-hematological cancers (14.9%). Mean mortality and hospitalization cost were high (25.5% and 12,000 euros, respectively). Conclusions: The results of this first nationwide study in Spain allow a change in the misconception that, after the AIDS epidemic, PcP is an infrequent disease, showing that today it is an emerging problem in patients without HIV infection. These findings underlines the need for increased efforts toward a better characterization of risk groups to improve prophylactic strategies and reduce the burden of disease.

20.
Clin Epidemiol ; 11: 615-624, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31413639

RESUMO

PURPOSE: Heart failure (HF) is a chronic, frequent and disabling condition but with a modifiable course and a large potential for improving. The aim of this study was to validate the two available clinical prediction rules for mortality at one year in patients with primo-hospitalization for decompensated HF: PREDICE and AHEAD. The secondary aim was to evaluate in our setting the changes in the clinical pattern of HF in the last decade in patients hospitalized for a first episode of the disease. PATIENTS AND METHODS: A prospective multicenter cohort study, which included 180 patients hospitalized with "de novo" HF was conducted to validate the PREDICE score. Calibration and discrimination measurements were calculated for the PREDICE model and the PREDICE score (using the validation cohort of the PREDICE) and the AHEAD score (using both the development and the validation cohort of the PREDICE). RESULTS: For the PREDICE models, the area under the curve (AUC) was 0.68 (95% confidence interval [CI]: 0.57-0.79) and the calibration slope 0.65 (95% CI: 0.21-1.20). For the PREDICE score AUC was 0.59 (95% CI: 0.47-0.71) and slope 0.42 (95% CI: -0.20-1.17). For the AHEAD score the AUC was 0.68 (95% CI: 0.62-0.73) and slope 1.38 (95% CI: 0.62-0.73) when used the development cohort of PREDICE and the AUC was 0.58 (95% CI: 0.49-0.67), and slope 0.68 (95% CI: -0.06 to 1.47) when used its validation cohort. CONCLUSION: The present study shows that the two risk scores available for patients with primo-hospitalization for decompensated HF (PREDICE and AHEAD) are not currently valid for predicting mortality at one-year. In our setting the clinical spectrum of hospitalized patients with new-onset HF has been modified over time. The study underscores the need to validate the prognostic models before clinical implementation.

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