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1.
BMC Bioinformatics ; 25(Suppl 1): 153, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38627615

RESUMO

BACKGROUND: With the rapid increase in throughput of long-read sequencing technologies, recent studies have explored their potential for taxonomic classification by using alignment-based approaches to reduce the impact of higher sequencing error rates. While alignment-based methods are generally slower, k-mer-based taxonomic classifiers can overcome this limitation, potentially at the expense of lower sensitivity for strains and species that are not in the database. RESULTS: We present MetageNN, a memory-efficient long-read taxonomic classifier that is robust to sequencing errors and missing genomes. MetageNN is a neural network model that uses short k-mer profiles of sequences to reduce the impact of distribution shifts on error-prone long reads. Benchmarking MetageNN against other machine learning approaches for taxonomic classification (GeNet) showed substantial improvements with long-read data (20% improvement in F1 score). By utilizing nanopore sequencing data, MetageNN exhibits improved sensitivity in situations where the reference database is incomplete. It surpasses the alignment-based MetaMaps and MEGAN-LR, as well as the k-mer-based Kraken2 tools, with improvements of 100%, 36%, and 23% respectively at the read-level analysis. Notably, at the community level, MetageNN consistently demonstrated higher sensitivities than the previously mentioned tools. Furthermore, MetageNN requires < 1/4th of the database storage used by Kraken2, MEGAN-LR and MMseqs2 and is > 7× faster than MetaMaps and GeNet and > 2× faster than MEGAN-LR and MMseqs2. CONCLUSION: This proof of concept work demonstrates the utility of machine-learning-based methods for taxonomic classification using long reads. MetageNN can be used on sequences not classified by conventional methods and offers an alternative approach for memory-efficient classifiers that can be optimized further.


Assuntos
Metagenômica , Viverridae , Animais , Metagenômica/métodos , Redes Neurais de Computação , Metagenoma , Aprendizado de Máquina , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Análise de Sequência de DNA/métodos
2.
Biochemistry ; 63(2): 230-240, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38150593

RESUMO

The first step of histidine biosynthesis in Acinetobacter baumannii, the condensation of ATP and 5-phospho-α-d-ribosyl-1-pyrophosphate to produce N1-(5-phospho-ß-d-ribosyl)-ATP (PRATP) and pyrophosphate, is catalyzed by the hetero-octameric enzyme ATP phosphoribosyltransferase, a promising target for antibiotic design. The catalytic subunit, HisGS, is allosterically activated upon binding of the regulatory subunit, HisZ, to form the hetero-octameric holoenzyme (ATPPRT), leading to a large increase in kcat. Here, we present the crystal structure of ATPPRT, along with kinetic investigations of the rate-limiting steps governing catalysis in the nonactivated (HisGS) and activated (ATPPRT) forms of the enzyme. A pH-rate profile showed that maximum catalysis is achieved above pH 8.0. Surprisingly, at 25 °C, kcat is higher when ADP replaces ATP as substrate for ATPPRT but not for HisGS. The HisGS-catalyzed reaction is limited by the chemical step, as suggested by the enhancement of kcat when Mg2+ was replaced by Mn2+, and by the lack of a pre-steady-state burst of product formation. Conversely, the ATPPRT-catalyzed reaction rate is determined by PRATP diffusion from the active site, as gleaned from a substantial solvent viscosity effect. A burst of product formation could be inferred from pre-steady-state kinetics, but the first turnover was too fast to be directly observed. Lowering the temperature to 5 °C allowed observation of the PRATP formation burst by ATPPRT. At this temperature, the single-turnover rate constant was significantly higher than kcat, providing additional evidence for a step after chemistry limiting catalysis by ATPPRT. This demonstrates allosteric activation by HisZ accelerates the chemical step.


Assuntos
ATP Fosforribosiltransferase , Acinetobacter baumannii , ATP Fosforribosiltransferase/química , Difosfatos , Acinetobacter baumannii/metabolismo , Domínio Catalítico , Cinética , Trifosfato de Adenosina/metabolismo , Catálise
3.
Apoptosis ; 29(1-2): 1-2, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37794219

RESUMO

Fas and Fas ligand (FasL)-induced cell death is critical for the appropriate regulation of immune responses, especially those mediated by T cells. In this letter, several studies are discussed that reinforce the importance of FasL intracellular signaling for CD4 + T cell death, which might involve PSTPIP phosphatase and/or MAPKs.


Assuntos
Apoptose , Receptor fas , Proteína Ligante Fas/genética , Transdução de Sinais , Morte Celular
4.
J Mol Evol ; 92(1): 3-20, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38281163

RESUMO

Innate immunity is present in all animals. In this review, we explore the main conserved mechanisms of recognition and innate immune responses among animals. In this sense, we discuss the receptors, critical for binding to pathogen-associated molecular patterns (PAMPs) or danger-associated molecular patterns (DAMPs); the downstream signaling proteins; and transcription factors that govern immune responses. We also highlight conserved inflammatory mediators that are induced after the recognition of DAMPs and PAMPs. At last, we discuss the mechanisms that are involved in the regulation and/or generation of reactive oxygen species (ROS), influencing immune responses, like heme-oxygenases (HOs).


Assuntos
Imunidade Inata , Moléculas com Motivos Associados a Patógenos , Animais , Imunidade Inata/genética , Alérgenos , Fatores de Transcrição , Proteínas de Transporte
5.
Chembiochem ; 25(7): e202400047, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38350003

RESUMO

The human enzyme 2'-deoxynucleoside 5'-phosphate N-hydrolase 1 (HsDNPH1) catalyses the hydrolysis of 5-hydroxymethyl-2'-deoxyuridine 5'-phosphate to generate 5-hydroxymethyluracil and 2-deoxyribose-5-phosphate via a covalent 5-phospho-2-deoxyribosylated enzyme intermediate. HsDNPH1 is a promising target for inhibitor development towards anticancer drugs. Here, site-directed mutagenesis of conserved active-site residues, followed by HPLC analysis of the reaction and steady-state kinetics are employed to reveal the importance of each of these residues in catalysis, and the reaction pH-dependence is perturbed by each mutation. Solvent deuterium isotope effects indicate no rate-limiting proton transfers. Crystal structures of D80N-HsDNPH1 in unliganded and substrate-bound states, and of unliganded D80A- and Y24F-HsDNPH1 offer atomic level insights into substrate binding and catalysis. The results reveal a network of hydrogen bonds involving the substrate and the E104-Y24-D80 catalytic triad and are consistent with a proposed mechanism whereby D80 is important for substrate positioning, for helping modulate E104 nucleophilicity, and as the general acid in the first half-reaction. Y24 positions E104 for catalysis and prevents a catalytically disruptive close contact between E104 and D80.


Assuntos
Fosfatos , Humanos , Sítios de Ligação/genética , Catálise , Domínio Catalítico , Concentração de Íons de Hidrogênio , Cinética
6.
Ann Surg Oncol ; 31(6): 3639-3648, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38530529

RESUMO

BACKGROUND: The impact of coronavirus disease 2019 (COVID-19) on postoperative recovery from oncology surgeries should be understood for the clinical decision-making. Therefore, this study was designed to evaluate the postoperative cumulative 28-day mortality and the morbidity of surgical oncology patients during the COVID-19 pandemic. METHODS: This retrospective cohort study included patients consecutively admitted to intensive care units (ICU) of three centres for postoperative care of oncologic surgeries between March to June 2019 (first phase) and March to June 2020 (second phase). The primary outcome was cumulative 28-day postoperative mortality. Secondary outcomes were postoperative organic dysfunction and the incidence of clinical complications. Because of the possibility of imbalance between groups, adjusted analyses were performed: Cox proportional hazards model (primary outcome) and multiple logistic regression model (secondary outcomes). RESULTS: After screening 328 patients, 291 were included. The proportional hazard of cumulative 28-day mortality was higher in the second phase than that in the first phase in the Cox model, with the adjusted hazard ratio of 4.35 (95% confidence interval [CI] 2.15-8.82). The adjusted incidences of respiratory complications (odds ratio [OR] 5.35; 95% CI 1.42-20.11) and pulmonary infections (OR 1.53; 95% CI 1.08-2.17) were higher in the second phase. However, the adjusted incidence of other infections was lower in the second phase (OR 0.78; 95% CI 0.67-0.91). CONCLUSIONS: Surgical oncology patients who underwent postoperative care in the intensive care unit during the COVID-19 pandemic had higher hazard of 28-day mortality. Furthermore, these patients had higher odds of respiratory complications and pulmonary infections. Trials registration The study is registered in the Brazilian Registry of Clinical Trials under the code RBR-8ygjpqm, UTN code U1111-1293-5414.


Assuntos
COVID-19 , Neoplasias , Complicações Pós-Operatórias , Humanos , COVID-19/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Retrospectivos , Neoplasias/cirurgia , Neoplasias/mortalidade , Complicações Pós-Operatórias/epidemiologia , Idoso , SARS-CoV-2 , Taxa de Sobrevida , Unidades de Terapia Intensiva/estatística & dados numéricos , Incidência , Prognóstico , Pandemias , Seguimentos
7.
Cytokine ; 173: 156408, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37925788

RESUMO

Cytokines are known for their pleiotropic effects. They can be classified by their function as pro-inflammatory, such as tumor necrosis factor (TNF), interleukin (IL) 1 and IL-12, or anti-inflammatory, like IL-10, IL-35 and transforming growth factor ß (TGF-ß). Though this type of classification is an important simplification for the understanding of the general cytokine's role, it can be misleading. Here, we discuss recent studies that show a dichotomic role of the so-called pro and anti-inflammatory cytokines, highlighting that their function can be dependent on the microenvironment and their concentrations. Furthermore, we discuss how the back-and-forth interplay between cytokines and immunometabolism can influence the dichotomic role of inflammatory responses as an important target to complement cytokine-based therapies.


Assuntos
Citocinas , Interleucina-1 , Citocinas/metabolismo , Fator de Necrose Tumoral alfa/metabolismo , Fator de Crescimento Transformador beta/metabolismo , Anti-Inflamatórios , Imunidade
8.
Toxicol Appl Pharmacol ; 491: 117045, 2024 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-39127352

RESUMO

Antiretrovirals have improved considerably since the introduction of 3'-azido-3'-deoxythymidine (zidovudine or AZT), a molecule with also anticancer effects. Subsequently, a variety of other nucleosides have been synthesized. However, these medications are often associated with serious adverse events and the onset or exacerbation of degenerative processes, diseases, and syndromes, affecting mainly the mitochondria. In this study, we used Caenorhabditis elegans to investigate the toxicity potential of AZT and three new organoselenium derivatives with modifications in the 5' position of the sugar ring in place of the 5'-OH group, with the insertion of a neutral, an electron-withdrawing and an electron-donating group attached to the aryl selenol moiety: 5'-seleno-(4-chloro-phenyl)-3-(amino)-thymidine (ASAT-4-Cl), 5'-seleno-(phenyl)-3-(amino)-thymidine (ASAT-Ph), and 5'-seleno-(4-methoxyphenyl)-3-(amino)- thymidine (ASAT-4-OMe). Analyzes included worm survival, behavior parameters, high-resolution respirometry, citrate synthase activity, and ATP levels. Although all compounds negatively affected C. elegans, ASAT-4-Cl and ASAT-Ph showed lower toxicity compared to AZT, especially in mitochondrial viability and ATP production. Therefore, more studies must be carried out on the use of these new compounds as pharmacological interventions.


Assuntos
Caenorhabditis elegans , Compostos Organosselênicos , Zidovudina , Animais , Caenorhabditis elegans/efeitos dos fármacos , Zidovudina/toxicidade , Compostos Organosselênicos/farmacologia , Compostos Organosselênicos/toxicidade , Mitocôndrias/efeitos dos fármacos , Fármacos Anti-HIV/toxicidade
9.
Exp Eye Res ; 238: 109745, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-38043763

RESUMO

The epiretinal membrane is a fibrocontractile tissue that forms on the inner surface of the retina, causing visual impairment ranging from mild to severe, and even retinal detachment. Müller glial cells actively participate in the formation of this membrane. Current research is constantly seeking for new therapeutic approaches that aim to prevent or treat cellular dysfunctions involved in the progression of this common fibrosis condition. The Rho GTPases signaling pathway regulates several processes associated with the epiretinal membrane, such as cell proliferation, migration, and contraction. Rho kinase (ROCK), an effector of the RhoA GTPase, is an interesting potential therapeutic target. This study aimed to evaluate the effects of a ROCK inhibitor (Y27632) on human Müller cells viability, growth, cytoskeletal organization, expression of extracellular matrix components, myofibroblast differentiation, migration, and contractility. Müller cells of the MIO-M1 lineage were cultured and treated for different periods with the inhibitor. Viability was evaluated by MTT assay and trypan blue exclusion method, and growth was evaluated by growth curve and BrdU incorporation assay. The actin cytoskeleton was stained with fluorescent phalloidin, intermediate filaments and microtubules were analyzed with immunofluorescence for vimentin and α-tubulin. Gene and protein expression of collagens I and V, laminin and fibronectin were evaluated by rt-PCR and immunofluorescence. Chemotactic and spontaneous cell migration were studied by transwell assay and time-lapse observation of live cells, respectively. Cell contractility was assessed by collagen gel contraction assay. The results showed that ROCK inhibition by Y27632 did not affect cell viability, but decreased cell growth and proliferation after 72 h. There was a change in cell morphology and organization of F-actin, with a reduction in the cell body, disappearance of stress fibers and formation of long, branched cell extensions. Microtubules and vimentin filaments were also affected, possibly because of F-actin alterations. The inhibitor also reduced gene expression and immunoreactivity of smooth muscle α-actin, a marker of myofibroblasts. The expression of extracellular matrix components was not affected by the inhibitor. Chemotactic cell migration showed no significant changes, while cell contractility was substantially reduced. No spontaneous migration of MIO-M1 cells was observed. In conclusion, pharmacological inhibition of ROCK in Müller cells could be a potentially promising approach to treat epiretinal membranes by preventing cell proliferation, contractility and transdifferentiation, without affecting cell viability.


Assuntos
Membrana Epirretiniana , Quinases Associadas a rho , Humanos , Actinas/metabolismo , Células Ependimogliais/metabolismo , Vimentina/metabolismo , Sobrevivência Celular , Membrana Epirretiniana/metabolismo , Células Cultivadas , Matriz Extracelular/metabolismo
10.
Langmuir ; 40(11): 5663-5672, 2024 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-38451216

RESUMO

The complex nature and structure of biomolecules and nanoparticles and their interactions make it challenging to achieve a deeper understanding of the dynamics at the nano-bio interface of enzymes and plasmonic nanoparticles subjected to light excitation. In this study, circular dichroism (CD) and Raman spectroscopic experiments and molecular dynamics (MD) simulations were used to investigate the potential changes at the nano-bio interface upon plasmonic excitation. Our data showed that photothermal and thermal heating induced distinct changes in the secondary structure of a model nanobioconjugate composed of lipase fromCandida antarcticafraction B (CALB) and gold nanoparticles (AuNPs). The use of a green laser led to a substantial decrease in the α-helix content of the lipase from 66% to 13% and an increase in the ß-sheet content from 5% to 31% compared to the initial conformation of the nanobioconjugate. In contrast, the differences under similar thermal heating conditions were only 55% and 11%, respectively. This study revealed important differences related to the enzyme secondary structure, enzyme-nanoparticle interactions, and the stability of the enzyme catalytic triad (Ser105-Asp187-His224), influenced by the instantaneous local temperature increase generated from photothermal heating compared to the slower rate of thermal heating of the bulk. These results provide valuable insights into the interactions between biomolecules and plasmonic nanoparticles induced by photothermal heating, advancing plasmonic biocatalysis and related fields.


Assuntos
Ouro , Nanopartículas Metálicas , Ouro/química , Lipase , Nanopartículas Metálicas/química , Luz , Lasers
11.
J Chem Ecol ; 50(5-6): 222-236, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38748380

RESUMO

In myrmecophilous organisms, which live in symbiosis with ants, cuticular hydrocarbons (CHCs) play a pivotal role in interspecific communication and defense against chemical-oriented predators. Although these interactions form complex information webs, little is known about the influence of biotic environmental factors on the CHC profiles of myrmecophiles. Here, we analyzed the effect of different host plants and tending ants on the larval CHC profile of Synargis calyce (Lepidoptera: Riodinidae), a polyphagous species with facultative myrmecophily. Groups of caterpillars were fed individually with three host plant species (without tending ants), and with two tending ant species. Through gas chromatography analysis, we compared the cuticular profiles of treatments and found a high similarity between plants and caterpillars (65-82%), but a low similarity between caterpillars and their tending ants (30 - 25%). Cluster analysis showed that caterpillars, ants, and plants form distinct groups, indicating that S. calyce caterpillars have their own chemical profile. These results are similar to those observed for Lycaenidae caterpillars indicating that there is functional convergence in the chemical strategies used by myrmecophilous caterpillar species with similar ecology. Also, the results suggest that the cuticular compounds of S. calyce are primarily influenced by their host plants rather than their tending ants. Thus, we propose that these caterpillars present a trade-off between camouflage and directly informing their presence to ants, maintaining their unique chemical profile, though slightly affected by biotic environmental factors.


Assuntos
Formigas , Hidrocarbonetos , Larva , Animais , Formigas/fisiologia , Formigas/química , Formigas/metabolismo , Hidrocarbonetos/metabolismo , Hidrocarbonetos/química , Hidrocarbonetos/análise , Larva/fisiologia , Larva/química , Simbiose , Borboletas/fisiologia , Borboletas/química
12.
Exp Parasitol ; 261: 108749, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38593864

RESUMO

Trypanosoma cruzi (T. cruzi) causes Chagas, which is a neglected tropical disease (NTD). WHO estimates that 6 to 7 million people are infected worldwide. Current treatment is done with benznidazole (BZN), which is very toxic and effective only in the acute phase of the disease. In this work, we designed, synthesized, and characterized thirteen new phenoxyhydrazine-thiazole compounds and applied molecular docking and in vitro methods to investigate cell cytotoxicity, trypanocide activity, nitric oxide (NO) production, cell death, and immunomodulation. We observed a higher predicted affinity of the compounds for the squalene synthase and 14-alpha demethylase enzymes of T. cruzi. Moreover, the compounds displayed a higher predicted affinity for human TLR2 and TLR4, were mildly toxic in vitro for most mammalian cell types tested, and LIZ531 (IC50 2.8 µM) was highly toxic for epimastigotes, LIZ311 (IC50 8.6 µM) for trypomastigotes, and LIZ331 (IC50 1.9 µM) for amastigotes. We observed that LIZ311 (IC50 2.5 µM), LIZ431 (IC50 4.1 µM) and LIZ531 (IC50 5 µM) induced 200 µg/mL of NO and JM14 induced NO production in three different concentrations tested. The compound LIZ331 induced the production of TNF and IL-6. LIZ311 induced the secretion of TNF, IFNγ, IL-2, IL-4, IL-10, and IL-17, cell death by apoptosis, decreased acidic compartment formation, and induced changes in the mitochondrial membrane potential. Taken together, LIZ311 is a promising anti-T. cruzi compound is not toxic to mammalian cells and has increased antiparasitic activity and immunomodulatory properties.


Assuntos
Doença de Chagas , Simulação de Acoplamento Molecular , Óxido Nítrico , Tiazóis , Tripanossomicidas , Trypanosoma cruzi , Trypanosoma cruzi/efeitos dos fármacos , Tiazóis/farmacologia , Tiazóis/química , Doença de Chagas/tratamento farmacológico , Doença de Chagas/imunologia , Humanos , Animais , Camundongos , Óxido Nítrico/metabolismo , Óxido Nítrico/biossíntese , Tripanossomicidas/farmacologia , Tripanossomicidas/química , Concentração Inibidora 50 , Potencial da Membrana Mitocondrial/efeitos dos fármacos , Hidrazinas/farmacologia , Hidrazinas/química , Citocinas/metabolismo , Camundongos Endogâmicos BALB C
13.
Neurosurg Rev ; 47(1): 490, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39190169

RESUMO

BACKGROUND: The L5-S1 interlaminar access described in 2006 by Ruetten et al. represented a paradigm shift and a new perspective on endoscopic spinal approaches. Since then, the spinal community has shown that both the traditional ipsilateral and novel contralateral interlaminar approaches to the L5-S1 foramen are good alternatives to transforaminal access. This study aimed to provide a technical description and brief case series analysis of a new endoscopic foraminal and extraforaminal approach for pathologies at the lumbar L5-S1 level using a new ipsilateral interlaminar approach. METHODS: Thirty patients with degenerative stenotic conditions at the L5-S1 disc level underwent the modified interlaminar approach. The surgical time, blood loss, occurrence of complications, and clinical outcomes were recorded. The data were compiled in Excel and analyzed using R software version 4.2. All continuous variables are presented as the mean, median, minimum, and maximal ranges. For categorical variables, data are described as counts and percentages. RESULTS: Thirty patients were included in the study. The cohort showed significant improvements in all quality-of-life scores (ODI, visual analog scale of back pain, and visual analog scale of leg pain). Five cases of postoperative numbness and three cases of postoperative dysesthesia have been reported. No case of durotomy or leg weakness has been reported. CONCLUSIONS: The fundamental change proposed by this procedure, the new ipsilateral approach, presents potential advantages to surgeons by overcoming anatomical challenges at the L5-S1 level and by providing surgeon-friendly visualization and access. This approach allows for extensive foraminal and extraforaminal decompression, including the removal of hernias and osteophytosis, without causing neural retraction of the L5-S1 roots while maintaining the stability of the operated level.


Assuntos
Descompressão Cirúrgica , Vértebras Lombares , Humanos , Feminino , Masculino , Descompressão Cirúrgica/métodos , Pessoa de Meia-Idade , Vértebras Lombares/cirurgia , Idoso , Adulto , Sacro/cirurgia , Endoscopia/métodos , Estenose Espinal/cirurgia , Resultado do Tratamento , Neuroendoscopia/métodos
14.
An Acad Bras Cienc ; 96(1): e20221048, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38597499

RESUMO

The cognitive deficit, which is like Alzheimer's disease and is associated with oxidative damage, may be induced by exposure to streptozotocin. This study aimed to evaluate if the tellurium-containing organocompound, 3j, 5'-arylchalcogeno-3-aminothymidine derivative, interferes with the effects of streptozotocin, as well as to investigate its toxicity in adult mice. Cognitive deficit was induced by two doses of streptozotocin (2.25 mg/kg/day, 48 h interval) intracerebroventricularly. After, the mice were subcutaneously treated with 3j (8.62 mg/kg/day) for 25 days. The effects were assessed by evaluating hippocampal and cortical acetylcholinesterase and behavioral tasks. 3j toxicity was investigated for 10 (0, 21.55, or 43.10 mg/kg/day) and 37 (0, 4.31, or 8.62 mg/kg/day) days by assessing biometric parameters and glucose and urea levels, and alanine aminotransferase activity in blood plasma. 3j exposure did not alter the behavioral alterations induced by streptozotocin exposure. On the other hand, 3j exposure normalized hippocampus acetylcholinesterase activity, which is enhanced by streptozotocin exposure. Toxicity evaluation showed that the administration of 3j for either 10 or 37 days did not cause harmful effects on the biometric and biochemical parameters analyzed. Therefore, 3j does not present any apparent toxicity and reverts acetylcholinesterase activity increase induced by streptozotocin in young adult mice.


Assuntos
Doença de Alzheimer , Transtornos Cognitivos , Camundongos , Animais , Acetilcolinesterase/metabolismo , Estreptozocina/toxicidade , Transtornos Cognitivos/induzido quimicamente , Transtornos Cognitivos/tratamento farmacológico , Estresse Oxidativo , Doença de Alzheimer/induzido quimicamente , Doença de Alzheimer/tratamento farmacológico , Hipocampo , Modelos Animais de Doenças
15.
Chem Biodivers ; 21(3): e202301960, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38196022

RESUMO

The fixed oil from the inner mesocarp of Caryocar coriaceum Wittm. is used in the Chapada do Araripe region of Brazil for the treatment of genitourinary candidiasis. This study aimed to evaluate the chemical composition, antifungal activity, reduction of fungal virulence, and the preliminary toxicity of the fixed oil from the inner mesocarp of C. coriaceum tested against three Candida yeasts. The oil was characterized by gas chromatography (GC-MS and GC-FID). Antifungal activity was assessed using the serial microdilution method. Additionally, the potential of the oil as an enhancer of fluconazole action was tested at sub-inhibitory concentrations (MIC/8). The mechanism of action of C. coriaceum fixed oil was determined by evaluating the inhibition of morphological transition in Candida spp. The chemical composition of the fixed oil of C. coriaceum comprised both unsaturated and saturated fatty acids. Oleic (61 %) and palmitic (33 %) acids were the major constituents. Regarding its anti-Candida activity, the oil inhibited the growth of C. albicans (IC50 : 371 µg/mL) and C. tropicalis (IC50 : 830 µg/mL). Furthermore, the oil reversed the antifungal resistance of C. albicans and C. tropicalis, restoring the susceptibility to fluconazole and reducing their IC50 from 12.33 µg/mL and 362 µg/mL to 0.22 µg/mL and 13.93 µg/mL, respectively. The fixed oil of C. coriaceum completely inhibited the morphological transition of C. albicans and C. tropicalis at a concentration of 512 µg/mL, but exhibited limited low antifungal potential against C. krusei. The observed antifungal activity may be attributed to the overproduction of reactive oxygen species. Additionally, the oil showed no toxic effect on the Drosophila melanogaster in vivo model. The fixed oil from the inner mesocarp of C. coriaceum emerge as a strong candidate for the development of new pharmaceutical formulations to treat infections caused by Candida spp.


Assuntos
Fluconazol , Malpighiales , Animais , Fluconazol/farmacologia , Candida , Antifúngicos/farmacologia , Antifúngicos/química , Drosophila melanogaster , Óleos de Plantas/farmacologia , Óleos de Plantas/química , Candida albicans , Testes de Sensibilidade Microbiana
16.
J Adv Nurs ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38523566

RESUMO

AIMS AND OBJECTIVES: To analyse the process of elaborating social representations about pressure injury preventive measures by the nursing team (nurses and nurse technicians) and how this process relates to preventive practices for hospitalized patients. DESIGN: Qualitative study, with the application of the theory of social representations in its procedural methodological approach. METHODS: The study was carried out in an inpatient clinic of a public hospital in the state of Rondônia, Brazil. Totally, 28 nursing professionals in the medical clinic sectors who had worked directly with patient care for more than 6 months participated. The data were collected between July and September 2021 via in-depth interviews with the application of a semi-structured instrument. Analysis was carried out with the help of ALCESTE software, which performed a lexicographic analysis, and also via thematic analysis. The COREQ guided the presentation of the research report. RESULTS: The social representations were developed based on the professionals' symbolic beliefs about the visibility/invisibility of the results of applying preventive care. These symbolic constructions mobilized positive and negative feelings among the nursing team, which guided the classification of prevention practices as being of greater or lesser priority among other care activities. There were favourable attitudes among professionals, which included applying prevention measures in their daily routines, and unfavourable attitudes of non-adherence to the institution's protocol for preventing pressure injuries. CONCLUSIONS: The nursing team's perception of pressure injury prevention is influenced by symbolic, affective, values, and social dimensions. Non-adherence behaviours are attributed to the belief in the invisibility of prevention outcomes, resulting in a reluctance to implement preventive measures. RELEVANCE TO CLINICAL PRACTICE: Understanding the subjective logic that explains the thinking and actions of the nursing team suggests the need to incorporate discussions on beliefs, values, sentiments, and attitudes of nursing professionals into educational programs on pressure injury prevention. PATIENT OR PUBLIC CONTRIBUTION: No public contribution.

17.
Int J Sport Nutr Exerc Metab ; 34(4): 199-206, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38458180

RESUMO

Carbohydrate (CHO) supplementation during endurance exercise can improve performance. However, it is unclear whether low glycemic index (GI) CHO leads to differential ergogenic and metabolic effects compared with a standard high GI CHO. This study investigated the ergogenic and metabolic effects of CHO supplementation with distinct GIs, namely, (a) trehalose (30 g/hr), (b) isomaltulose (30 g/hr), (c) maltodextrin (60 g/hr), and (d) placebo (water). In this double-blind, crossover, counterbalanced, placebo-controlled study, 13 male cyclists cycled a total of 100 min at varied exercise intensity (i.e., 10-min stages at 1.5, 2.0, and 2.5 W/kg; repeated three times plus two 5-min stages at 1.0 W/kg before and after the protocol), followed by a 20-min time trial on four separated occasions. Blood glucose and lactate (every 20 min), heart rate, and ratings of perceived exertion were collected throughout, and muscle biopsies were taken before and immediately after exercise. The results showed that trehalose improved time-trial performance compared with placebo (total work done 302 ± 39 vs. 287 ± 48 kJ; p = .01), with no other differences between sessions (all p ≥ .07). Throughout the 100-min protocol, blood glucose was higher with maltodextrin compared with the other supplements at all time points (all p < .05). Heart rate, ratings of perceived exertion, muscle glycogen content, blood glucose, and lactate were not different between conditions when considering the 20-min time trial (all p > .05). Trehalose supplementation throughout endurance exercise improved cycling performance and appears to be an appropriate CHO source for exercise tasks up to 2 hr. No ergogenic superiority between the different types of CHO was established.


Assuntos
Desempenho Atlético , Ciclismo , Glicemia , Estudos Cross-Over , Frequência Cardíaca , Isomaltose , Ácido Láctico , Polissacarídeos , Trealose , Humanos , Masculino , Ciclismo/fisiologia , Método Duplo-Cego , Trealose/administração & dosagem , Trealose/farmacologia , Desempenho Atlético/fisiologia , Adulto , Glicemia/metabolismo , Glicemia/efeitos dos fármacos , Frequência Cardíaca/efeitos dos fármacos , Ácido Láctico/sangue , Polissacarídeos/administração & dosagem , Polissacarídeos/farmacologia , Isomaltose/análogos & derivados , Isomaltose/administração & dosagem , Isomaltose/farmacologia , Suplementos Nutricionais , Índice Glicêmico , Resistência Física/efeitos dos fármacos , Resistência Física/fisiologia , Músculo Esquelético/efeitos dos fármacos , Músculo Esquelético/metabolismo , Fenômenos Fisiológicos da Nutrição Esportiva , Substâncias para Melhoria do Desempenho/administração & dosagem , Substâncias para Melhoria do Desempenho/farmacologia , Carboidratos da Dieta/administração & dosagem , Adulto Jovem , Esforço Físico/fisiologia , Esforço Físico/efeitos dos fármacos , Glicogênio/metabolismo
18.
JAMA ; 332(5): 380-389, 2024 08 06.
Artigo em Inglês | MEDLINE | ID: mdl-38762797

RESUMO

Importance: Current treatments for idiopathic pulmonary fibrosis slow the rate of lung function decline, but may be associated with adverse events that affect medication adherence. In phase 2 trials, pamrevlumab (a fully human monoclonal antibody that binds to and inhibits connective tissue growth factor activity) attenuated the progression of idiopathic pulmonary fibrosis without substantial adverse events. Objective: To assess the efficacy and safety of pamrevlumab for patients with idiopathic pulmonary fibrosis. Design, Setting, and Participants: Phase 3 randomized clinical trial including 356 patients aged 40 to 85 years with idiopathic pulmonary fibrosis who were not receiving antifibrotic treatment with nintedanib or pirfenidone at enrollment. Patients were recruited from 117 sites in 9 countries between July 18, 2019, and July 29, 2022; the last follow-up encounter occurred on August 28, 2023. Interventions: Pamrevlumab (30 mg/kg administered intravenously every 3 weeks; n = 181) or placebo (n = 175) for 48 weeks. Main Outcomes and Measures: The primary outcome was absolute change in forced vital capacity (FVC) from baseline to week 48. There were 5 secondary outcomes (including time to disease progression, which was defined as a decline of ≥10% in predicted FVC or death). The exploratory outcomes included patient-reported symptoms. Adverse events were reported. Results: Among 356 patients (mean age, 70.5 years; 258 [72.5%] were men; 221 [62.1%] were White), 277 (77.8%) completed the trial. There was no significant between-group difference for absolute change in FVC from baseline to week 48 (least-squares mean, -260 mL [95% CI, -350 to -170 mL] in the pamrevlumab group vs -330 mL [95% CI, -430 to -230 mL] in the placebo group; mean between-group difference, 70 mL [95% CI, -60 to 190 mL], P = .29). There were no significant between-group differences in any of the secondary outcomes or in the patient-reported outcomes. In the pamrevlumab group, there were 160 patients (88.4%) with treatment-related adverse events and 51 patients (28.2%) with serious adverse events vs 151 (86.3%) and 60 (34.3%), respectively, in the placebo group. During the study, 23 patients died in each group (12.7% in the pamrevlumab group vs 13.1% in the placebo group). Conclusions and Relevance: Among patients with idiopathic pulmonary fibrosis treated with pamrevlumab or placebo, there was no statistically significant between-group difference for the primary outcome of absolute change in FVC from baseline to week 48. Trial Registration: ClinicalTrials.gov Identifier: NCT03955146.


Assuntos
Anticorpos Monoclonais Humanizados , Fibrose Pulmonar Idiopática , Humanos , Fibrose Pulmonar Idiopática/tratamento farmacológico , Masculino , Feminino , Anticorpos Monoclonais Humanizados/uso terapêutico , Anticorpos Monoclonais Humanizados/efeitos adversos , Pessoa de Meia-Idade , Idoso , Capacidade Vital , Adulto , Método Duplo-Cego , Idoso de 80 Anos ou mais , Progressão da Doença , Fator de Crescimento do Tecido Conjuntivo
19.
Genet Mol Biol ; 47(3): e20230313, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39136576

RESUMO

Chromosomal Microarray Analysis (CMA) has increased the comprehension of the mechanisms of copy number variation (CNV) formation, classification of these rearrangements, type of recurrence, and its origin, and has also been a powerful approach to identifying CNVs in individuals with intellectual disability. The aim of this study was to establish the parental origin of de novo pathogenic CNV in a cohort of patients with intellectual disability from the public health system of Goiás-Brazil. CMA was done in 76 trios and we identified 15 de novo pathogenic CNVs in 12 patients with intellectual disability. In a total of 15 de novo pathogenic CNV, 60% were derived from the maternal germline and 40% from the paternal germline. CNV flanked by low copy repeats (LCR) were identified in 46.7% and most of them were of maternal origin. No significant association was observed between paternal age and the mutation rate of de novo CNVs. The presence of high-identity LCRs increases the occurrence of CNV formation mediated by non-allelic homologous recombination and the majority of paternal CNVs are non-recurrent. The mechanism of formation of these CNV may have been by microhomology-mediated break-induced replication or non-homologous end joining.

20.
Environ Monit Assess ; 196(6): 534, 2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38727864

RESUMO

Escherichia coli is one of the key bacteria responsible for a variety of diseases in humans and livestock-associated infections around the globe. It is the leading cause of mortality in neonatal and weaned piglets in pig husbandry, causing diarrhea and significant harm to the industry. Furthermore, the frequent and intensive use of antimicrobials for the prevention of diseases, particularly gastrointestinal diseases, may promote the selection of multidrug-resistant (MDR) strains. These resistant genotypes can be transmitted through the excrement of animals, including swine. It is common practice to use porcine manure processed by biodigesters as fertilizer. This study aimed to examine the antimicrobial susceptibility, the presence of virulence genes frequently associated with pathotypes of intestinal pathogenic E. coli (InPEC), and antimicrobial resistance genes (ARGs) of 28 E. coli isolates collected from swine manure fertilizers. In addition, the enterobacterial repetitive intergenic consensus-PCR (ERIC-PCR) technique was used to investigate the genetic relationship among the strains. Using disk diffusion, the antimicrobial susceptibility profiles of the strains were determined. Using polymerase chain reaction (PCR), 14 distinct virulence genes associated with the most prevalent diarrhea and intestinal pathogenic E. coli (DEC/InPEC) and five ARGs were analyzed. All isolates tested positive for multidrug resistance. There was no detection of any of the 14 virulence genes associated with InPECs, indicating the presence of an avirulent commensal microbiota. Molecular classification by ERIC-PCR revealed that the majority of isolates (27 isolates) coalesced into a larger cluster with a genetic similarity of 47.7%; only one strain did not cluster in this cluster, indicating a high level of genetic diversity among the analyzed isolates. Thus, it is of the utmost importance to conduct epidemiological surveillance of animal breeding facilities in order to determine their microbiota and formulate plans to reduce the use of antimicrobials and improve animal welfare.


Assuntos
Farmacorresistência Bacteriana Múltipla , Escherichia coli , Fertilizantes , Esterco , Animais , Suínos , Escherichia coli/genética , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Esterco/microbiologia , Brasil , Farmacorresistência Bacteriana Múltipla/genética , Antibacterianos/farmacologia
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