Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 281
Filtrar
Mais filtros

Bases de dados
Tipo de documento
Intervalo de ano de publicação
1.
Nat Immunol ; 19(6): 617-624, 2018 06.
Artigo em Inglês | MEDLINE | ID: mdl-29760533

RESUMO

Humoral immune responses to microbial polysaccharide surface antigens can prevent bacterial infection but are typically strain specific and fail to mediate broad protection against different serotypes. Here we describe a panel of affinity-matured monoclonal human antibodies from peripheral blood immunoglobulin M-positive (IgM+) and IgA+ memory B cells and clonally related intestinal plasmablasts, directed against the lipopolysaccharide (LPS) O-antigen of Klebsiella pneumoniae, an opportunistic pathogen and major cause of antibiotic-resistant nosocomial infections. The antibodies showed distinct patterns of in vivo cross-specificity and protection against different clinically relevant K. pneumoniae serotypes. However, cross-specificity was not limited to K. pneumoniae, as K. pneumoniae-specific antibodies recognized diverse intestinal microbes and neutralized not only K. pneumoniae LPS but also non-K. pneumoniae LPS. Our data suggest that the recognition of minimal glycan epitopes abundantly expressed on microbial surfaces might serve as an efficient humoral immunological mechanism to control invading pathogens and the large diversity of the human microbiota with a limited set of cross-specific antibodies.


Assuntos
Anticorpos Antibacterianos/imunologia , Especificidade de Anticorpos/imunologia , Klebsiella pneumoniae/imunologia , Antígenos O/imunologia , Anticorpos Monoclonais/imunologia , Reações Cruzadas/imunologia , Humanos
2.
RNA ; 29(10): 1557-1574, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37460154

RESUMO

Assemblysomes are EDTA- and RNase-resistant ribonucleoprotein (RNP) complexes of paused ribosomes with protruding nascent polypeptide chains. They have been described in yeast and human cells for the proteasome subunit Rpt1, and the disordered amino-terminal part of the nascent chain was found to be indispensable for the accumulation of the Rpt1-RNP into assemblysomes. Motivated by this, to find other assemblysome-associated RNPs we used bioinformatics to rank subunits of Saccharomyces cerevisiae protein complexes according to their amino-terminal disorder propensity. The results revealed that gene products involved in DNA repair are enriched among the top candidates. The Sgs1 DNA helicase was chosen for experimental validation. We found that indeed nascent chains of Sgs1 form EDTA-resistant RNP condensates, assemblysomes by definition. Moreover, upon exposure to UV, SGS1 mRNA shifted from assemblysomes to polysomes, suggesting that external stimuli are regulators of assemblysome dynamics. We extended our studies to human cell lines. The BLM helicase, ortholog of yeast Sgs1, was identified upon sequencing assemblysome-associated RNAs from the MCF7 human breast cancer cell line, and mRNAs encoding DNA repair proteins were overall enriched. Using the radiation-resistant A549 cell line, we observed by transmission electron microscopy that 1,6-hexanediol, an agent known to disrupt phase-separated condensates, depletes ring ribosome structures compatible with assemblysomes from the cytoplasm of cells and makes the cells more sensitive to X-ray treatment. Taken together, these findings suggest that assemblysomes may be a component of the DNA damage response from yeast to human.


Assuntos
Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Humanos , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , RecQ Helicases/genética , Ácido Edético/metabolismo , Dano ao DNA , RNA/metabolismo , Ribonucleoproteínas/genética , Ribossomos/genética , Ribossomos/metabolismo
3.
Physiol Plant ; 176(4): e14504, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39191700

RESUMO

Plant infections caused by fungi lead to significant crop losses worldwide every year. This study aims to better understand the plant defence mechanisms regulated by red light, in particular, the effects of red light at night when most phytopathogens are highly infectious. Our results showed that superoxide production significantly increased immediately after red light exposure and, together with hydrogen peroxide levels, was highest at dawn after 30 min of nocturnal red-light treatment. In parallel, red-light-induced expression and increased the activities of several antioxidant enzymes. The nocturnal red light did not affect salicylic acid but increased jasmonic acid levels immediately after illumination, whereas abscisic acid levels increased 3 h after nocturnal red-light exposure at dawn. Based on the RNAseq data, red light immediately increased the transcription of several chloroplastic chlorophyll a-b binding protein and circadian rhythm-related genes, such as Constans 1, CONSTANS interacting protein 1 and zinc finger protein CONSTANS-LIKE 10. In addition, the levels of several transcription factors were also increased after red light exposure, such as the DOF zinc finger protein and a MYB transcription factor involved in the regulation of circadian rhythms and defence responses in tomato. In addition to identifying these key transcription factors in tomato, the application of red light at night for one week not only reactivated key antioxidant enzymes at the gene and enzyme activity level at dawn but also contributed to a more efficient and successful defence against Botrytis cinerea infection.


Assuntos
Botrytis , Regulação da Expressão Gênica de Plantas , Luz , Doenças das Plantas , Solanum lycopersicum , Botrytis/fisiologia , Solanum lycopersicum/microbiologia , Solanum lycopersicum/genética , Solanum lycopersicum/efeitos da radiação , Solanum lycopersicum/fisiologia , Doenças das Plantas/microbiologia , Doenças das Plantas/imunologia , Regulação da Expressão Gênica de Plantas/efeitos da radiação , Oxilipinas/metabolismo , Ciclopentanos/metabolismo , Proteínas de Plantas/metabolismo , Proteínas de Plantas/genética , Ácido Abscísico/metabolismo , Fatores de Transcrição/metabolismo , Fatores de Transcrição/genética , Ácido Salicílico/metabolismo , Ritmo Circadiano/fisiologia , Ritmo Circadiano/efeitos da radiação , Reguladores de Crescimento de Plantas/metabolismo , Peróxido de Hidrogênio/metabolismo , Luz Vermelha
4.
Arch Virol ; 169(5): 100, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38630394

RESUMO

In this study, a novel genotype of genogroup X (GX) sapovirus (family Caliciviridae) was detected in the small intestinal contents of a golden jackal (Canis aureus) in Hungary and characterised by viral metagenomics and next-generation sequencing techniques. The complete genome of the detected strain, GX/Dömsöd/DOCA-11/2020/HUN (PP105600), is 7,128 nt in length. The ORF1- and ORF2-encoded viral proteins (NSP, VP1, and VP2) have 98%, 95%, and 88% amino acid sequence identity to the corresponding proteins of genogroup GX sapoviruses from domestic pigs, but the nucleic acid sequence identity values for their genes are significantly lower (83%, 77%, and 68%). During an RT-PCR-based epidemiological investigation of additional jackal and swine samples, no other GX strains were detected, but a GXI sapovirus strain, GXI/Tótfalu/WBTF-10/2012/HUN (PP105601), was identified in a faecal sample from a wild boar (Sus scrofa). We report the detection of members of two likely underdiagnosed groups of sapoviruses (GX and GXI) in a golden jackal and, serendipitously, in a wild boar in Europe.


Assuntos
Caliciviridae , Canidae , Sapovirus , Animais , Suínos , Sapovirus/genética , Chacais , Hungria/epidemiologia , Genótipo , Sus scrofa
5.
Nucleic Acids Res ; 50(4): 2258-2269, 2022 02 28.
Artigo em Inglês | MEDLINE | ID: mdl-35150281

RESUMO

The ribosome is a fundamental biomolecular complex that synthesizes proteins in cells. Nascent proteins emerge from the ribosome through a tunnel, where they may interact with the tunnel walls or small molecules such as antibiotics. These interactions can cause translational arrest with notable physiological consequences. Here, we studied the arrest caused by the regulatory peptide VemP, which is known to form α-helices inside the ribosome tunnel near the peptidyl transferase center under specific conditions. We used all-atom molecular dynamics simulations of the entire ribosome and circular dichroism spectroscopy to study the driving forces of helix formation and how VemP causes the translational arrest. To that aim, we compared VemP dynamics in the ribosome tunnel with its dynamics in solution. We show that the VemP peptide has a low helical propensity in water and that the propensity is higher in mixtures of water and trifluorethanol. We propose that helix formation within the ribosome is driven by the interactions of VemP with the tunnel and that a part of VemP acts as an anchor. This anchor might slow down VemP progression through the tunnel enabling α-helix formation, which causes the elongation arrest.


Assuntos
Peptidil Transferases , Ribossomos , Peptídeos/metabolismo , Peptidil Transferases/metabolismo , Biossíntese de Proteínas , Dobramento de Proteína , Estrutura Secundária de Proteína , Proteínas/metabolismo , Ribossomos/metabolismo , Água/metabolismo
6.
BMC Public Health ; 24(1): 1073, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632614

RESUMO

INTRODUCTION: Problematic usage of the internet (PUI) is perhaps one of the most frequently studied phenomena of the 21st century receiving increasing attention in both scientific literature and the media. Despite intensive research there have been relatively few meaningful studies among elementary school students in Hungary and worldwide, who may be considered as a high-risk population with regard to problematic internet use. The aim of our study was to carry out a complex research focusing on the prevalence and risk factors of PUI among elementary school children aged 10-15 years (Grade 5-8). METHODS: Demographics included were gender, age, place of stay, type of residence, family type, parental education, start of internet use, used devices, daily internet use, purpose of internet use, internet accounts, ways of keeping in touch with friends and sporting activities. PUI was evaluated using the paper-based version of the Potentially Problematic Use of the Internet Questionnaire. RESULTS: Overall, 2000 paper-based questionnaires were successfully delivered and the final analysis included 1168 responses (overall response rate 58.4%). Mean age was 12.55 ± 1.24 years. Female gender (OR = 2.760, p = 0,006, CI 95% 0.065 to 0.384), younger age (11-12 years) (OR = 3.812, p < 0.001, 95% CI: 1.747-4.731), early exposure to the internet (OR = 3.466, p = 0.001, 95% CI 1.535-5.446), living in a small village (OR = 1.081, p = 0.002, 95% CI 1.041-1.186) urgency to answer online (OR = 4.677, p < 0.001, 95% CI: 2.714-6.639), decreased frequency of personal contact with friends (OR = 2.897, p = 0.004, 95% CI: 1.037-1.681), spending more than 6 h online (OR = 12.913, p < 0.001, 95% CI: 10.798-14.892), morning and nighttime internet use (OR = 3.846, p < 0.001, CI 95% 1.886-5.810) and never doing any sports (OR = 2.016, p = 0.044, 95% CI: 1.050-3.354) were independently associated with problematic internet use. CONCLUSIONS: Based on the results of our questionnaire survey more than 10% seemed to be problematic users in our study population, which is a relatively high rate. Early exposure to the internet as well as younger age were strongly related to this phenomenon. Duration of being online as well as daily time interval of internet use are important predisposing factors. Scarcely studied social factors such as being online at the expense of personal relationships and the lack of physical activity should be payed more attention to prevent the development of PUI.


Assuntos
Comportamento Aditivo , Instituições Acadêmicas , Criança , Humanos , Feminino , Adolescente , Estudos Transversais , Hungria , Estudantes , Inquéritos e Questionários , Internet , Comportamento Aditivo/epidemiologia
7.
Entropy (Basel) ; 26(5)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38785635

RESUMO

The focus of our research is the examination of Hermitian curves over finite fields, specifically concentrating on places of degree three and their role in constructing Hermitian codes. We begin by studying the structure of the Riemann-Roch space associated with these degree-three places, aiming to determine essential characteristics such as the basis. The investigation then turns to Hermitian codes, where we analyze both functional and differential codes of degree-three places, focusing on their parameters and automorphisms. In addition, we explore the study of subfield subcodes and trace codes, determining their structure by giving lower bounds for their dimensions. This presents a complex problem in coding theory. Based on numerical experiments, we formulate a conjecture for the dimension of some subfield subcodes of Hermitian codes. Our comprehensive exploration seeks to deepen the understanding of Hermitian codes and their associated subfield subcodes related to degree-three places, thus contributing to the advancement of algebraic coding theory and code-based cryptography.

8.
Chembiochem ; 24(22): e202300431, 2023 11 16.
Artigo em Inglês | MEDLINE | ID: mdl-37768852

RESUMO

The function of cellobiose dehydrogenase (CDH) in biosensors, biofuel cells, and as a physiological redox partner of lytic polysaccharide monooxygenase (LPMO) is based on its role as an electron donor. Before donating electrons to LPMO or electrodes, an interdomain electron transfer from the catalytic FAD-containing dehydrogenase domain to the electron shuttling cytochrome domain of CDH is required. This study investigates the role of two crucial amino acids located at the dehydrogenase domain on domain interaction and interdomain electron transfer by structure-based engineering. The electron transfer kinetics of wild-type Myriococcum thermophilum CDH and its variants M309A, R698S, and M309A/R698S were analyzed by stopped-flow spectrophotometry and structural effects were studied by small-angle X-ray scattering. The data show that R698 is essential to pull the cytochrome domain close to the dehydrogenase domain and orient the heme propionate group towards the FAD, while M309 is an integral part of the electron transfer pathway - its mutation reducing the interdomain electron transfer 10-fold. Structural models and molecular dynamics simulations pinpoint the action of these two residues on the domain interaction and interdomain electron transfer.


Assuntos
Desidrogenases de Carboidrato , Elétrons , Aminoácidos/metabolismo , Proteínas Fúngicas/química , Transporte de Elétrons , Desidrogenases de Carboidrato/química , Oxigenases de Função Mista/metabolismo , Polissacarídeos/metabolismo , Citocromos/metabolismo
9.
Chemistry ; 29(21): e202203798, 2023 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-36719326

RESUMO

The introduction of a phenolate pendant arm in place of an acetate on AAZTA- and DATA-like ligands resulted in hepta- and hexadentate chelators able to form Ga(III) complexes with thermodynamic stability and kinetic inertness higher than that of other Ga(III) complexes based on the parent 6-amino-6-methylperhydro-1,4-diazepine scaffold. In particular, the heptadentate AAZ3A-endoHB with a phenolate arm on an endocyclic N-atom shows a logKGaL of 27.35 and a remarkable resistance to hydroxide coordination up to basic pH (pH>9). This behaviour allows to also improve the kinetic inertness of the complex showing a dissociation half-life (t1/2 ) at pH 7.4 of 76 h. Although also the hexadentate AAZ2A-exoHB chelator forms a stable (logKGaL =24.69) and inert (t1/2 =33 h at pH 7.4) Ga(III) complex, the 68 Ga labelling showed a better radiochemical yield with AAZ3A-endoHB, especially at room temperature. Thus, a bifunctional chelator of AAZ3A-endoHB was synthesized bearing an isothiocyanate group that was conjugated to the N-terminus of a c(RGD) peptide for integrin receptor targeting. Finally, the conjugate was successfully labelled with 68 Ga isotope, and the resulting radiotracer tested for its stability in human serum and then in vivo for targeting B16-F10 tumours with miniPET imaging.


Assuntos
Quelantes , Neoplasias , Humanos , Quelantes/química , Braço , Radioisótopos de Gálio/química , Compostos Radiofarmacêuticos/química , Tomografia por Emissão de Pósitrons/métodos
10.
Arch Virol ; 168(4): 108, 2023 Mar 11.
Artigo em Inglês | MEDLINE | ID: mdl-36899117

RESUMO

In this study, a novel vesivirus (family Caliciviridae) was detected and characterized in faecal and tissue (blood and spleen) specimens collected from three (23.1%) out of 13 European badgers (Meles meles) in Hungary that were tested using RT-PCR and sequencing methods. The complete genome of the vesivirus strain European badger/B40/2021/HUN (OQ161773) is 8,375 nucleotides in length. The ORF1, ORF2, and ORF3 proteins have 81.1%, 70.5%, and 64.2% amino acid sequence identity, respectively, to the corresponding proteins of Asian badger vesivirus, which was first reported in badgers in China in 2022. These results indicate that more than one lineage/species of vesiviruses circulates in mustelid badgers in geographically different regions.


Assuntos
Mustelidae , Vesivirus , Animais , Hungria , Mustelidae/genética , China
11.
Clin Chem Lab Med ; 61(7): 1167-1198, 2023 06 27.
Artigo em Inglês | MEDLINE | ID: mdl-36989417

RESUMO

OBJECTIVES: Antinuclear antibodies (ANA) are important for the diagnosis of various autoimmune diseases. ANA are usually detected by indirect immunofluorescence assay (IFA) using HEp-2 cells (HEp-2 IFA). There are many variables influencing HEp-2 IFA results, such as subjective visual reading, serum screening dilution, substrate manufacturing, microscope components and conjugate. Newer developments on ANA testing that offer novel features adopted by some clinical laboratories include automated computer-assisted diagnosis (CAD) systems and solid phase assays (SPA). METHODS: A group of experts reviewed current literature and established recommendations on methodological aspects of ANA testing. This process was supported by a two round Delphi exercise. International expert groups that participated in this initiative included (i) the European Federation of Clinical Chemistry and Laboratory Medicine (EFLM) Working Group "Autoimmunity Testing"; (ii) the European Autoimmune Standardization Initiative (EASI); and (iii) the International Consensus on ANA Patterns (ICAP). RESULTS: In total, 35 recommendations/statements related to (i) ANA testing and reporting by HEp-2 IFA; (ii) HEp-2 IFA methodological aspects including substrate/conjugate selection and the application of CAD systems; (iii) quality assurance; (iv) HEp-2 IFA validation/verification approaches and (v) SPA were formulated. Globally, 95% of all submitted scores in the final Delphi round were above 6 (moderately agree, agree or strongly agree) and 85% above 7 (agree and strongly agree), indicating strong international support for the proposed recommendations. CONCLUSIONS: These recommendations are an important step to achieve high quality ANA testing.


Assuntos
Anticorpos Antinucleares , Doenças Autoimunes , Humanos , Doenças Autoimunes/diagnóstico , Técnica Indireta de Fluorescência para Anticorpo/métodos , Padrões de Referência , Linhagem Celular Tumoral
12.
Dermatology ; 239(4): 592-600, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37019083

RESUMO

BACKGROUND: Intestinal symptoms are common in patients with hidradenitis suppurativa (HS). HS patients may experience a broad spectrum of chronic inflammatory intestinal disorders (CIID), not exclusive to inflammatory bowel diseases, which are diagnosed by colonoscopy and intestinal biopsies. The frequency of CIID in patients with HS has not been investigated. OBJECTIVE: The objectives of this study were to determine the occurrence of CIID in HS and characterize this clinical population. Furthermore, the feasibility of using faecal calprotectin (FC) test or anti-Saccharomyces cerevisiae antibody (ASCA) levels to assess the colonic inflammation of CIID in HS patients was investigated. METHODS: All newly diagnosed and untreated HS patients (n = 74) were referred to a gastroenterologist for FC followed by colonoscopy after informed consent. C-reactive protein (CRP), white blood cell count, nucleotide-binding oligomerization-domain-containing protein 2 (NOD2) polymorphism, and ASCA levels were measured. Patients were divided into HS-only and HS with CIID (HS + CIID) groups, based on the absence or presence of CIID. Laboratory and clinical parameters (age, gender, HS onset, clinical stage, family history, body mass index (BMI), smoking) were compared between the groups. RESULTS: Thirteen patients complained gastrointestinal symptoms prior to any examination, including 11 in the HS + CIID group. The CIID frequency in HS was 28.4% (n = 21/74), based on colonoscopy and histology. Significantly more patients had severe disease state in the HS + CIID group compared with the HS-only group, and BMI was significantly lower in the HS + CIID group (28.20 ± 5.58 vs. 32.74 ± 6.45, p = 0.006). FC positivity occurred significantly more in HS + CIID patients compared with HS-only patients (90.48% vs. 3.77%, p < 0.001), and ASCA IgG levels were significantly elevated in HS + CIID patients (22.08 ± 23.07 vs. 8.41 ± 10.94 U/mL, p = 0.001). The FC test identified HS + CIID patients with 96.23% specificity and 91.3% sensitivity, while ASCA displayed 77.8% sensitivity and 76.3% specificity. Blood count, CRP, and the presence of NOD2 polymorphisms were indifferent between the two groups. CONCLUSION: A high frequency of CIID was detected in the examined HS population. The noninvasive FC test has high sensitivity and specificity for diagnosing CIID in HS patients. Concomitant CIID and HS may indicate the need for an early-start for biological treatment.


Assuntos
Hidradenite Supurativa , Humanos , Hidradenite Supurativa/complicações , Hidradenite Supurativa/diagnóstico , Hidradenite Supurativa/tratamento farmacológico , Fumar , Proteína C-Reativa/metabolismo , Índice de Gravidade de Doença
13.
Oral Dis ; 29(7): 2756-2764, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35611648

RESUMO

OBJECTIVE: One-third of the Hungarian population suffers from xerostomia. Since there is no evidence of the actual prevalence of Sjögren's syndrome (SS) in Hungary, this study aimed to evaluate the same. MATERIALS AND METHODS: Data were collected from the Faculty of Dentistry, Semmelweis University from 2008 to 2015. A diagnosis of SS was established based on the American College of Rheumatology and European League Against Rheumatism criteria. RESULTS: Of the 1076 patients examined with sicca symptoms, 188 patients had confirmed SS. Primary SS (pSS) was diagnosed in 135 patients and secondary SS (sSS) was confirmed in 53 patients. According to the available statistical records of the public health service of Hungary, there were an average of 16 (0.0014%, 5-26) newly diagnosed SS cases in the entire population and 141 SS patient-practitioner consultations (49-232) per 100,000 inhabitants in the country over the past 10 years (based on the past 10 years: 2011-2020). CONCLUSION: Results revealed that approximately 1/5th-1/6th of patients with sicca symptoms have SS, among whom 72% and 285 have pSS and sSS, respectively. Global Hungarian records simultaneously revealed that the number of both new diagnoses and doctor-SS patient encounters has significantly decreased (by 50%) yearly over the last decade.


Assuntos
Síndrome de Sjogren , Xerostomia , Humanos , Estados Unidos , Síndrome de Sjogren/complicações , Síndrome de Sjogren/epidemiologia , Síndrome de Sjogren/diagnóstico , Hungria/epidemiologia , Prevalência , Xerostomia/epidemiologia , Xerostomia/complicações
14.
Int J Mol Sci ; 24(15)2023 Jul 26.
Artigo em Inglês | MEDLINE | ID: mdl-37569316

RESUMO

Huntington's disease (HD) is a fatal neurodegenerative disorder caused by the expansion of a CAG trinucleotide repeat in the Huntingtin gene. Transcriptional dysregulation is one of the main cellular processes affected by mutant Huntingtin (mHtt). In this study, we investigate the alterations in miRNA and mRNA expression levels in a Drosophila model of HD by RNA sequencing and assess the functional effects of misregulated miRNAs in vivo. We found that in head samples of HD flies, the level of 32 miRNAs changed significantly; half of these were upregulated, while the other half were downregulated. After comparing miRNA and mRNA expression data, we discovered similarities in the impacted molecular pathways. Additionally, we observed that the putative targets of almost all dysregulated miRNAs were overrepresented among the upregulated mRNAs. We tested the effects of overexpression of five misregulated miRNAs in the HD model and found that while mir-10 and mir-219 enhanced, mir-137, mir-305, and mir-1010 ameliorated mHtt-induced phenotypes. Based on our results, we propose that while altered expression of mir-10, mir-137, and mir-1010 might be part of HD pathology, the upregulation of mir-305 might serve as a compensatory mechanism as a response to mHtt-induced transcriptional dysregulation.


Assuntos
Doença de Huntington , MicroRNAs , Animais , Doença de Huntington/metabolismo , MicroRNAs/genética , MicroRNAs/metabolismo , Repetições de Trinucleotídeos , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Proteína Huntingtina/genética , Modelos Animais de Doenças
15.
Int J Mol Sci ; 24(5)2023 Feb 24.
Artigo em Inglês | MEDLINE | ID: mdl-36901890

RESUMO

ABCB4 is almost exclusively expressed in the liver, where it plays an essential role in bile formation by transporting phospholipids into the bile. ABCB4 polymorphisms and deficiencies in humans are associated with a wide spectrum of hepatobiliary disorders, attesting to its crucial physiological function. Inhibition of ABCB4 by drugs may lead to cholestasis and drug-induced liver injury (DILI), although compared with other drug transporters, there are only a few identified substrates and inhibitors of ABCB4. Since ABCB4 shares up to 76% identity and 86% similarity in the amino acid sequence with ABCB1, also known to have common drug substrates and inhibitors, we aimed to develop an ABCB4 expressing Abcb1-knockout MDCKII cell line for transcellular transport assays. This in vitro system allows the screening of ABCB4-specific drug substrates and inhibitors independently of ABCB1 activity. Abcb1KO-MDCKII-ABCB4 cells constitute a reproducible, conclusive, and easy to use assay to study drug interactions with digoxin as a substrate. Screening a set of drugs with different DILI outcomes proved that this assay is applicable to test ABCB4 inhibitory potency. Our results are consistent with prior findings concerning hepatotoxicity causality and provide new insights for identifying drugs as potential ABCB4 inhibitors and substrates.


Assuntos
Doença Hepática Induzida por Substâncias e Drogas , Colestase , Humanos , Polimorfismo Genético , Sequência de Aminoácidos , Colestase/metabolismo , Bile/metabolismo
16.
Crit Care ; 26(1): 217, 2022 07 16.
Artigo em Inglês | MEDLINE | ID: mdl-35842675

RESUMO

BACKGROUND: Neurologic manifestations are increasingly reported in patients with coronavirus disease 2019 (COVID-19). Yet, data on prevalence, predictors and relevance for outcome of neurological manifestations in patients requiring intensive care are scarce. We aimed to characterize prevalence, risk factors and impact on outcome of neurologic manifestations in critically ill COVID-19 patients. METHODS: In the prospective, multicenter, observational registry study PANDEMIC (Pooled Analysis of Neurologic DisordErs Manifesting in Intensive care of COVID-19), we enrolled COVID-19 patients with neurologic manifestations admitted to 19 German intensive care units (ICU) between April 2020 and September 2021. We performed descriptive and explorative statistical analyses. Multivariable models were used to investigate factors associated with disorder categories and their underlying diagnoses as well as to identify predictors of outcome. RESULTS: Of the 392 patients included in the analysis, 70.7% (277/392) were male and the mean age was 65.3 (SD ± 3.1) years. During the study period, a total of 2681 patients with COVID-19 were treated at the ICUs of 15 participating centers. New neurologic disorders were identified in 350 patients, reported by these centers, suggesting a prevalence of COVID-19-associated neurologic disorders of 12.7% among COVID-19 ICU patients. Encephalopathy (46.2%; 181/392), cerebrovascular (41.0%; 161/392) and neuromuscular disorders (20.4%; 80/392) were the most frequent categories identified. Out of 35 cerebrospinal fluid analyses with reverse transcriptase PCR for SARS-COV-2, only 3 were positive. In-hospital mortality was 36.0% (140/389), and functional outcome (mRS 3 to 5) of surviving patients was poor at hospital discharge in 70.9% (161/227). Intracerebral hemorrhage (OR 6.2, 95% CI 2.5-14.9, p < 0.001) and acute ischemic stroke (OR 3.9, 95% CI 1.9-8.2, p < 0.001) were the strongest predictors of poor outcome among the included patients. CONCLUSIONS: Based on this well-characterized COVID-19 ICU cohort, that comprised 12.7% of all severe ill COVID-19 patients, neurologic manifestations increase mortality and morbidity. Since no reliable evidence of direct viral affection of the nervous system by COVID-19 could be found, these neurologic manifestations may for a great part be indirect para- or postinfectious sequelae of the infection or severe critical illness. Neurologic ICU complications should be actively searched for and treated.


Assuntos
COVID-19 , Hemorragia Cerebral , AVC Isquêmico , Doenças do Sistema Nervoso , Idoso , COVID-19/complicações , COVID-19/epidemiologia , Hemorragia Cerebral/virologia , Estado Terminal/epidemiologia , Estado Terminal/terapia , Feminino , Humanos , Unidades de Terapia Intensiva , AVC Isquêmico/virologia , Masculino , Pessoa de Meia-Idade , Doenças do Sistema Nervoso/virologia , Pandemias , Estudos Prospectivos , Sistema de Registros , SARS-CoV-2
17.
Neurocrit Care ; 36(1): 148-156, 2022 02.
Artigo em Inglês | MEDLINE | ID: mdl-34331202

RESUMO

BACKGROUND: Altered pupillary function may reflect nonconvulsive status epilepticus (NCSE). Neurological pupil index (NPi) assessed by automated pupillometry is a surrogate marker of global pupillary function. We aimed to assess NPi changes in relation to NCSE treatment response. METHODS: In this prospective observational study, serial automated pupillometry was performed in 68 NCSE episodes. In accordance with local standards, patients were treated with clonazepam (1-2 mg), levetiracetam (40 mg/kg), and lacosamide (5 mg/kg) in a stepwise approach under continuous electroencephalography monitoring until NCSE was terminated. Patients with refractory NCSE received individualized regimens. NPi was assessed bilaterally before and after each treatment step. For statistical analysis, the lower NPi of both sides (minNPi) was used. Nonparametric testing for matched samples and Cohen's d to estimate effect size were performed. Principal component analysis was applied to assess the contribution of baseline minNPi, age, sex, and NCSE duration to treatment outcome. RESULTS: In 97.1% of 68 episodes, NCSE could be terminated; in 16.2%, NCSE was refractory. In 85.3% of episodes, an abnormal baseline minNPi ≤ 4.0 was obtained. After NCSE termination, minNPi increased significantly (p < 0.001). Cohen's d showed a strong effect size of 1.24 (95% confidence interval 0.88-1.61). Baseline minNPi was higher in clonazepam nonresponders vs. responders (p = 0.008), minNPi increased in responders (p < 0.001) but not in nonresponders. NCSE refractivity was associated with normal baseline minNPi (principal component analysis, component 1, 32.6% of variance, r = 0.78), male sex, and longer NCSE duration (component 2, 27.1% of variance, r = 0.62 and r = 0.78, respectively). CONCLUSIONS: Automated pupillometry may be a helpful noninvasive neuromonitoring tool for the assessment of patients with NCSE and response to treatment.


Assuntos
Eletroencefalografia , Estado Epiléptico , Humanos , Masculino , Monitorização Fisiológica , Estudos Prospectivos , Estado Epiléptico/diagnóstico , Estado Epiléptico/tratamento farmacológico , Resultado do Tratamento
18.
Int J Mol Sci ; 23(20)2022 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-36293420

RESUMO

d-Arabinofuranosyl-pyrimidine and -purine nucleoside analogues containing alkylthio-, acetylthio- or 1-thiosugar substituents at the C2' position were prepared from the corresponding 3',5'-O-silylene acetal-protected nucleoside 2'-exomethylenes by photoinitiated, radical-mediated hydrothiolation reactions. Although the stereochemical outcome of the hydrothiolation depended on the structure of both the thiol and the furanoside aglycone, in general, high d-arabino selectivity was obtained. The cytotoxic effect of the arabinonucleosides was studied on tumorous SCC (mouse squamous cell) and immortalized control HaCaT (human keratinocyte) cell lines by MTT assay. Three pyrimidine nucleosides containing C2'-butylsulfanylmethyl or -acetylthiomethyl groups showed promising cytotoxicity at low micromolar concentrations with good selectivity towards tumor cells. SAR analysis using a methyl ß-d-arabinofuranoside reference compound showed that the silyl-protecting group, the nucleobase and the corresponding C2' substituent are crucial for the cell growth inhibitory activity. The effects of the three most active nucleoside analogues on parameters indicative of cytotoxicity, such as cell size, division time and cell generation time, were investigated by near-infrared live cell imaging, which showed that the 2'-acetylthiomethyluridine derivative induced the most significant functional and morphological changes. Some nucleoside analogues also exerted anti-SARS-CoV-2 and/or anti-HCoV-229E activity with low micromolar EC50 values; however, the antiviral activity was always accompanied by significant cytotoxicity.


Assuntos
COVID-19 , Nucleosídeos de Pirimidina , Tioaçúcares , Humanos , Camundongos , Animais , Arabinonucleosídeos/química , Arabinonucleosídeos/farmacologia , Nucleosídeos/farmacologia , Nucleosídeos/química , Antivirais/farmacologia , Acetais , Compostos de Sulfidrila/química , Purinas , Relação Estrutura-Atividade
19.
Saudi Pharm J ; 30(2): 132-137, 2022 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-35528851

RESUMO

Background: The pharmacist career is constantly adapting to societal and health care needs. The past decade has seen a growing demand for curricular development to align graduation outcome with workforce competencies. Objective: This study aims to identify expectations for both didactic and experiential components of a new curriculum based on young pharmacist practitioner views. Methods: An online survey questionnaire was used in 2019-2020 to evaluate the pharmacy curriculum to detect indicators or key areas which require comprehensive reform. Results: The predominant majority of the 205 study participants recommended reduction in credit hours for Natural Sciences (78.54%) and a similar increase in the Theoretical and Practical Expertise Module (77.9%). Pharmaceutical care, clinical therapeutics and clinical pharmacy competencies should also be more highlighted in the program. Findings indicate the current training does not prepare for problem-solving and daily workplace challenges (72.7%) or for extended pharmacist skills and competencies (71.71%). Results show inconsistency in practical training experience, as all respondents participated in practical training for drug manufacturing and analysis but 61.0% reported no hands-on skills training in a hospital-clinical simulation setting. Indications for practitioner involvement into the natural sciences and biomedical subjects (86.3%) confirm the obvious need for more practice-oriented education. Conclusions: Educational reforms seem to be inevitable to achieve measurable improvement in professional practice and skills competency. The country specific demand for a needs-based pharmacy education reflects global trends but may also provide useful insights for individual transitions to transform education through practice and improve practice through education.

20.
Int J Mol Sci ; 23(1)2021 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-35008628

RESUMO

Inhibitory neurons innervating the perisomatic region of cortical excitatory principal cells are known to control the emergence of several physiological and pathological synchronous events, including epileptic interictal spikes. In humans, little is known about their role in synchrony generation, although their changes in epilepsy have been thoroughly investigated. This paper demonstraits how parvalbumin (PV)- and type 1 cannabinoid receptor (CB1R)-positive perisomatic interneurons innervate pyramidal cell bodies, and their role in synchronous population events spontaneously emerging in the human epileptic and non-epileptic neocortex, in vitro. Quantitative electron microscopy showed that the overall, PV+ and CB1R+ somatic inhibitory inputs remained unchanged in focal cortical epilepsy. On the contrary, the size of PV-stained synapses increased, and their number decreased in epileptic samples, in synchrony generating regions. Pharmacology demonstrated-in conjunction with the electron microscopy-that although both perisomatic cell types participate, PV+ cells have stronger influence on the generation of population activity in epileptic samples. The somatic inhibitory input of neocortical pyramidal cells remained almost intact in epilepsy, but the larger and consequently more efficient somatic synapses might account for a higher synchrony in this neuron population. This, together with epileptic hyperexcitability, might make a cortical region predisposed to generate or participate in hypersynchronous events.


Assuntos
Sincronização Cortical/fisiologia , Epilepsia/fisiopatologia , Neocórtex/fisiopatologia , Inibição Neural/fisiologia , Potenciais de Ação , Adulto , Idoso , Idoso de 80 Anos ou mais , Epilepsia/patologia , Feminino , Humanos , Interneurônios/metabolismo , Interneurônios/ultraestrutura , Masculino , Pessoa de Meia-Idade , Neocórtex/patologia , Neocórtex/ultraestrutura , Parvalbuminas/metabolismo , Receptores de Canabinoides/metabolismo , Sinapses/patologia , Sinapses/ultraestrutura
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA