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1.
Cell ; 179(6): 1357-1369.e16, 2019 11 27.
Artículo en Inglés | MEDLINE | ID: mdl-31761533

RESUMEN

Ribosome assembly is an efficient but complex and heterogeneous process during which ribosomal proteins assemble on the nascent rRNA during transcription. Understanding how the interplay between nascent RNA folding and protein binding determines the fate of transcripts remains a major challenge. Here, using single-molecule fluorescence microscopy, we follow assembly of the entire 3' domain of the bacterial small ribosomal subunit in real time. We find that co-transcriptional rRNA folding is complicated by the formation of long-range RNA interactions and that r-proteins self-chaperone the rRNA folding process prior to stable incorporation into a ribonucleoprotein (RNP) complex. Assembly is initiated by transient rather than stable protein binding, and the protein-RNA binding dynamics gradually decrease during assembly. This work questions the paradigm of strictly sequential and cooperative ribosome assembly and suggests that transient binding of RNA binding proteins to cellular RNAs could provide a general mechanism to shape nascent RNA folding during RNP assembly.


Asunto(s)
Pliegue del ARN , ARN Ribosómico/metabolismo , Proteínas de Unión al ARN/metabolismo , Modelos Biológicos , Conformación de Ácido Nucleico , Unión Proteica , Estabilidad del ARN , ARN Ribosómico/química , Transcripción Genética
2.
Cell ; 165(4): 1002-11, 2016 May 05.
Artículo en Inglés | MEDLINE | ID: mdl-27114037

RESUMEN

Studies of long-lived individuals have revealed few genetic mechanisms for protection against age-associated disease. Therefore, we pursued genome sequencing of a related phenotype-healthy aging-to understand the genetics of disease-free aging without medical intervention. In contrast with studies of exceptional longevity, usually focused on centenarians, healthy aging is not associated with known longevity variants, but is associated with reduced genetic susceptibility to Alzheimer and coronary artery disease. Additionally, healthy aging is not associated with a decreased rate of rare pathogenic variants, potentially indicating the presence of disease-resistance factors. In keeping with this possibility, we identify suggestive common and rare variant genetic associations implying that protection against cognitive decline is a genetic component of healthy aging. These findings, based on a relatively small cohort, require independent replication. Overall, our results suggest healthy aging is an overlapping but distinct phenotype from exceptional longevity that may be enriched with disease-protective genetic factors. VIDEO ABSTRACT.


Asunto(s)
Envejecimiento/genética , Estudio de Asociación del Genoma Completo , Longevidad , Anciano , Anciano de 80 o más Años , Enfermedad de Alzheimer/genética , Envejecimiento Cognitivo , Estudios de Cohortes , Enfermedad de la Arteria Coronaria/genética , Femenino , Predisposición Genética a la Enfermedad , Humanos , Masculino
3.
BMC Biol ; 22(1): 115, 2024 May 20.
Artículo en Inglés | MEDLINE | ID: mdl-38764040

RESUMEN

BACKGROUND: Thromboinflammation is caused by mutual activation of platelets and neutrophils. The site of thromboinflammation is determined by chemoattracting agents release by endothelium, immune cells, and platelets. Impaired neutrophil chemotaxis contributes to the pathogenesis of Shwachman-Diamond syndrome (SDS). In this hereditary disorder, neutrophils are known to have aberrant chemoattractant-induced F-actin properties. Here, we aim to determine whether neutrophil chemotaxis could be analyzed using our previously developed ex vivo assay of the neutrophils crawling among the growing thrombi. METHODS: Adult and pediatric healthy donors, alongside with pediatric patients with SDS, were recruited for the study. Thrombus formation and granulocyte movement in hirudinated whole blood were visualized by fluorescent microscopy in fibrillar collagen-coated parallel-plate flow chambers. Alternatively, fibrinogen, fibronectin, vWF, or single tumor cells immobilized on coverslips were used. A computational model of chemokine distribution in flow chamber with a virtual neutrophil moving in it was used to analyze the observed data. RESULTS: The movement of healthy donor neutrophils predominantly occurred in the direction and vicinity of thrombi grown on collagen or around tumor cells. For SDS patients or on coatings other than collagen, the movement was characterized by randomness and significantly reduced velocities. Increase in wall shear rates to 300-500 1/s led to an increase in the proportion of rolling neutrophils. A stochastic algorithm simulating leucocyte chemotaxis movement in the calculated chemoattractant field could reproduce the experimental trajectories of moving neutrophils for 72% of cells. CONCLUSIONS: In samples from healthy donors, but not SDS patients, neutrophils move in the direction of large, chemoattractant-releasing platelet thrombi growing on collagen.


Asunto(s)
Neutrófilos , Trombosis , Humanos , Neutrófilos/fisiología , Trombosis/fisiopatología , Quimiotaxis , Adulto , Niño , Masculino , Quimiotaxis de Leucocito , Femenino , Movimiento Celular
4.
Chembiochem ; 25(7): e202300848, 2024 Apr 02.
Artículo en Inglés | MEDLINE | ID: mdl-38353515

RESUMEN

We have recently discovered that ester-stabilized phosphorus ylides, resulting from deprotonation of a phosphonium salt such as [Ph3PCH2COOR], can transfer protons across artificial and biological membranes. To create more effective cationic protonophores, we synthesized similar phosphonium salts with one ((heptyloxycarbonylmethyl)(p-tolyl)bromide) or two ((butyloxycarbonylmethyl)(3,5-xylyl)osphonium bromide) methyl substituents in the phenyl groups. The methylation enormously augmented both protonophoric activity of the ylides on planar bilayer lipid membrane (BLM) and uncoupling of mammalian mitochondria, which correlated with strongly accelerated flip-flop of their cationic precursors across the BLM.


Asunto(s)
Mitocondrias Hepáticas , Fósforo , Animales , Mitocondrias Hepáticas/metabolismo , Fósforo/metabolismo , Ésteres/metabolismo , Bromuros/metabolismo , Metilación , Membrana Dobles de Lípidos/metabolismo , Mamíferos
5.
Ann Surg Oncol ; 31(8): 4956-4965, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38386198

RESUMEN

BACKGROUND: Novel definitions suggest that resectability status for pancreatic ductal adenocarcinoma (PDAC) should be assessed beyond anatomical criteria, considering both biological and conditional factors. This has, however, yet to be validated on a nationwide scale. This study evaluated the prognostic value of biological and conditional factors for staging of patients with resectable PDAC. PATIENTS AND METHODS: A nationwide observational cohort study was performed, including all consecutive patients who underwent upfront resection of National Comprehensive Cancer Network resectable PDAC in the Netherlands (2014-2019) with complete information on preoperative carbohydrate antigen (CA) 19-9 and Eastern Cooperative Oncology Group (ECOG) performance status. PDAC was considered biologically unfavorable (RB+) if CA19-9 ≥ 500 U/mL and favorable (RB-) otherwise. ECOG ≥ 2 was considered conditionally unfavorable (RC+) and favorable otherwise (RC-). Overall survival (OS) was assessed using Kaplan-Meier and Cox-proportional hazard analysis, presented as hazard ratios (HRs) with 95% confidence interval (CI). RESULTS: Overall, 688 patients were analyzed with a median overall survival (OS) of 20 months (95% CI 19-23). OS was 14 months (95% CI 10 months-median not reached) in 20 RB+C+ patients (3%; HR 1.61, 95% CI 0.86-2.70), 13 months (95% CI 11-15) in 156 RB+C- patients (23%; HR 1.86, 95% CI 1.50-2.31), and 21 months (95% CI 12-41) in 47 RB-C+ patients (7%; HR 1.14, 95% CI 0.80-1.62) compared with 24 months (95% CI 22-27) in 465 patients with RB-C- PDAC (68%; reference). CONCLUSIONS: Survival after upfront resection of anatomically resectable PDAC is worse in patients with CA19-9 ≥ 500 U/mL, while performance status had no impact. This supports consideration of CA19-9 in preoperative staging of resectable PDAC.


Asunto(s)
Carcinoma Ductal Pancreático , Estadificación de Neoplasias , Pancreatectomía , Neoplasias Pancreáticas , Humanos , Neoplasias Pancreáticas/cirugía , Neoplasias Pancreáticas/patología , Femenino , Masculino , Anciano , Tasa de Supervivencia , Carcinoma Ductal Pancreático/cirugía , Carcinoma Ductal Pancreático/patología , Estudios de Seguimiento , Pronóstico , Persona de Mediana Edad , Países Bajos/epidemiología , Antígeno CA-19-9/sangre , Biomarcadores de Tumor
6.
Ophthalmology ; 131(8): 880-891, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38307466

RESUMEN

PURPOSE: A recent genome-wide association study of age-related macular degeneration (AMD) identified new AMD-associated risk variants. These variants now can be incorporated into an updated polygenic risk score (PRS). This study aimed to assess the performance of an updated PRS, PRS2023, in an independent cohort of older individuals with retinal imaging data and to compare performance with an older PRS, PRS2016. DESIGN: Cross-sectional study. PARTICIPANTS: A total of 4175 participants of European ancestry, 70 years of age or older, with genotype and retinal imaging data. METHODS: We used logistic regression models and area under the receiver operating characteristic curve (AUC) to assess the performance of PRS2023 compared with PRS2016. AMD status and severity were graded using color fundus photography. MAIN OUTCOME MEASURES: Association of PRS2023 and PRS2016 with AMD risk at baseline. RESULTS: At enrollment among 4175 participants, 2605 participants (62.4%) had no AMD and 853 participants (20.4%), 671 participants (16.1%), and 46 participants (1.1%) had early, intermediate, and late-stage AMD, respectively. More than 27% of the participants with a high PRS2023 (top quartile) had intermediate or late-stage AMD, compared with < 15% for those in the middle 2 quartiles and less than 13% for those in the lowest quartile. Both PRS2023 and PRS2016 were associated significantly with AMD after adjustment for age, sex, smoking status, and lipid levels, with increasing odds ratios (ORs) for worsening AMD grades. PRS2023 outperformed PRS2016 (P = 0.03 for all AMD and P = 0.03 for late AMD, DeLong test comparing AUC). PRS2023 was associated with late-stage AMD with an adjusted OR of 5.05 (95% confidence interval [CI], 3.41-7.47) per standard deviation. The AUC of a model containing conventional or nongenetic risk factors and PRS2023 was 91% (95% CI, 87%-95%) for predicting late-stage AMD, which improved 12% over the model without the PRS (AUC, 79%; P < 0.001 for difference). CONCLUSIONS: A new PRS, PRS2023, for AMD outperforms a previous PRS and predicts increasing risk for late-stage AMD (with stronger association for more severe imaging-confirmed AMD grades). Our findings have clinical implications for the improved prediction and risk stratification of AMD. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.


Asunto(s)
Estudio de Asociación del Genoma Completo , Degeneración Macular , Curva ROC , Humanos , Masculino , Femenino , Anciano , Estudios Transversales , Factores de Riesgo , Degeneración Macular/genética , Degeneración Macular/diagnóstico , Anciano de 80 o más Años , Polimorfismo de Nucleótido Simple , Área Bajo la Curva , Medición de Riesgo/métodos , Predisposición Genética a la Enfermedad , Herencia Multifactorial , Valor Predictivo de las Pruebas , Genotipo , Puntuación de Riesgo Genético
7.
Langmuir ; 40(18): 9414-9425, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38651693

RESUMEN

Emulsions have become a crucial product form in various industries in modern times. Expanding the class of substances used to stabilize emulsions can improve their stability or introduce new properties. Particularly, the use of stimuli-responsive microgels makes it possible to create "smart" emulsions whose stability can be controlled by changing any of the specified stimuli. Thus, finding new ways to stabilize emulsions may broaden their application. In this work, for the first time, we applied microgels based on interpenetrating polymeric networks (IPNs) of poly(N-isopropylacrylamide) (PNIPAM) and poly(acrylic acid) (PAA) as stabilizing agents for "oil-in-water" emulsions. We have demonstrated that emulsions stabilized by such soft particles can remain colloidally stable for an extended period, even after being heated up to 40 °C, which is above the lower critical solution temperature (LCST) of PNIPAM. On the contrary, the emulsions stabilized by PNIPAM homopolymer microgels were broken upon heating. To understand the stabilization mechanism of the emulsions, mesoscopic computer simulations were performed to study the IPN microgels at the liquid-liquid interface. The simulations demonstrated that when the first subnetwork (PNIPAM) collapses, the particle adopts a flattened core-shell morphology with a highly swollen PAA-rich shell and a collapsed PNIPAM-rich core. Unlike its PNIPAM homopolymer counterpart, the IPN microgel maintains its three-dimensional shape, which provides stability to the microgel-based emulsions over a wide range of temperatures. Our combined findings could be useful in developing new approaches to emulsions' storage, biphasic catalysis, and lubrication of mechanisms in various operating and climatic conditions.

8.
Pediatr Res ; 95(4): 966-973, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37872237

RESUMEN

BACKGROUND: Platelets are blood cells responsible for the prevention of blood loss upon vessel wall disruption. It has been demonstrated that platelet functioning differs significantly between adult and pediatric donors. This study aimed to identify potential differences between the protein composition of platelets of pediatric, adolescent, and adult donors. METHODS: Platelet functional testing was conducted with live cell flow cytometry. Using a straightforward approach to platelet washing based on the sequential platelets centrifugation-resuspension, we were able to obtain stable and robust proteomics results, which corresponded to previously published data. RESULTS: We have identified that pediatric donors' platelets have increased amounts of proteins, responsible for mitochondrial activity, proteasome activity, and vesicle transport. Flow cytometry analysis of platelet intracellular signaling and functional responses revealed that platelets of the pediatric donors have diminished granule secretion and increased quiescent platelet calcium concentration and decreased calcium mobilization in response to ADP. We could explain the observed changes in calcium responses by the increased mitochondria protein content, and the changes in granule secretion could be explained by the differences in vesicle transport protein content. CONCLUSIONS: Therefore, we can conclude that the age-dependence of platelet functional responses originates from the difference in platelet protein content. IMPACT: Platelets of infants are known to functionally differ from the platelet of adult donors, although the longevity and persistivity of these differences are debatable. Pediatric donor platelets have enhanced amounts of mitochondrial, proteasomal, and vesicle transport proteins. Platelets of the pediatric donors had increased cytosolic calcium in the resting state, what is explained by the increased numbers of mitochondrial proteins. Infants had decreased platelet granule release, which resolved upon adolescence. Thus, platelets of the infants should be assessed differently from adult platelets. Differences in platelet proteomic contents persisted in adolescent groups, yet, no significant differences in platelet function were observed.


Asunto(s)
Calcio , Proteómica , Adulto , Adolescente , Humanos , Niño , Calcio/metabolismo , Plaquetas/metabolismo , Hemorragia , Hemostasis
9.
Eur J Haematol ; 112(4): 554-565, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38083800

RESUMEN

OBJECTIVES: Flow cytometry with adenosine diphosphate (ADP) allows to characterize molecular changes of platelet function caused by this physiologically important activation, but the methodology has not been thoroughly investigated, standardized and characterized yet. We analyzed the influence of several major variables and chose optimal conditions for platelet function assessment. METHODS: For activation, 2.5 µM CaCl2 , 5 µM ADP and antibodies were added to diluted blood and incubated for 15 min. We analyzed kinetics of antibody binding and effects of their addition sequence, agonist concentration, blood dilution, exogenous calcium addition and platelet fixation. RESULTS: We tested our protocol on 11 healthy children, 22 healthy adult volunteers, 9 patients after a month on dual antiplatelet therapy after percutaneous coronary intervention (PCI), 7 adult patients and 14 children with immune thrombocytopenia (ITP). We found that our protocol is highly sensitive to ADP stimulation with low percentage of aggregates formation. The assay is also sensitive to platelet function inhibition in post-PCI patients. Finally, platelet preactivation with ITP plasma was stronger and caused increase in activation response to ADP stimulation compared to preactivation with low dose of ADP. CONCLUSIONS: Our assay is sensitive to antiplatelet therapy and platelet preactivation in ITP patients under physiological conditions with minimal percentage of aggregates formation.


Asunto(s)
Intervención Coronaria Percutánea , Púrpura Trombocitopénica Idiopática , Adulto , Niño , Humanos , Citometría de Flujo/métodos , Plaquetas/metabolismo , Púrpura Trombocitopénica Idiopática/terapia , Púrpura Trombocitopénica Idiopática/tratamiento farmacológico , Adenosina Difosfato/farmacología , Adenosina Difosfato/metabolismo , Adenosina Difosfato/uso terapéutico , Inhibidores de Agregación Plaquetaria/farmacología , Inhibidores de Agregación Plaquetaria/uso terapéutico , Agregación Plaquetaria , Activación Plaquetaria
10.
Org Biomol Chem ; 2024 Sep 10.
Artículo en Inglés | MEDLINE | ID: mdl-39254682

RESUMEN

Flow hydrogenation performed over heterogeneous catalysts makes organic synthesis more economical, safe and environmentally friendly. Over the past two decades, a significant amount of research with a major focus on noble metal catalysts has been carried out in this area. However, catalysts based on non-noble metals (Ni, Cu, Co, etc.) are more promising for practical use due to their low cost and high availability. This review article discusses the use of supported and bulk non-noble metal catalysts for the liquid-phase hydrogenation of bi- and polyfunctional organic compounds in flow mode. The main attention is paid to the selective reduction of one functional group (NO2, CC, CN, CO, and CN) in the presence of other substituents. In addition, cascade synthetic protocols involving hydrogenation are presented.

11.
Xenobiotica ; 54(1): 18-25, 2024 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-38153086

RESUMEN

The dose proportionality and bioavailability of the potential anti-inflammatory and neuroprotective JNK inhibitor 11H-indeno[1,2-b]quinoxalin-11-one oxime (IQ-1) were evaluated by comparing pharmacokinetic parameters after single oral (25, 50 and 100 mg/kg) and intravenous (1 mg/kg) IQ-1 administration in rats.IQ-1 and its major metabolite ketone 11H-indeno[1,2-b]quinoxalin-11-one (IQ-18) were isolated from plasma samples by liquid-liquid extraction. IQ-1 (E-isomer) and IQ-18 were simultaneously quantified in plasma by the validated method of liquid chromatography with triple quadrupole mass spectrometry (HPLC-MS/MS).The absolute bioavailability of IQ-1 was < 1.5%. Cmax values were 24.72 ± 4.30, 25.66 ± 7.11 and 37.61 ± 3.53 ng/mL after single oral administration of IQ-1 at doses of 25, 50 and 100 mg/kg, respectively. IQ-1 exhibited dose proportionality at 50-100 mg/kg dose levels, whereas its pharmacokinetics was not dose proportional over the range of 25-50 mg/kg. IQ-18 demonstrated the invariance of the dose-normalized Cmax.In this study we systematically elucidated the absorption characteristics of IQ-1 in rat gastrointestinal tract and provided better understanding of IQ-1 pharmacology for the future development of a new formulations and therapeutic optimisation.


Asunto(s)
Quinoxalinas , Espectrometría de Masas en Tándem , Ratas , Animales , Disponibilidad Biológica , Administración Intravenosa , Cromatografía Líquida de Alta Presión/métodos , Administración Oral
12.
Biochemistry (Mosc) ; 89(3): 523-542, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-38648770

RESUMEN

Less than ten years ago, evidence began to accumulate about association between the changes in the composition of gut microbiota and development of human synucleinopathies, in particular sporadic form of Parkinson's disease. We collected data from more than one hundred and thirty experimental studies that reported similar results and summarized the frequencies of detection of different groups of bacteria in these studies. It is important to note that it is extremely rare that a unidirectional change in the population of one or another group of microorganisms (only an elevation or only a reduction) was detected in the patients with Parkinson's disease. However, we were able to identify several groups of bacteria that were overrepresented in the patients with Parkinson's disease in the analyzed studies. There are various hypotheses about the molecular mechanisms that explain such relationships. Usually, α-synuclein aggregation is associated with the development of inflammatory processes that occur in response to the changes in the microbiome. However, experimental evidence is accumulating on the influence of bacterial proteins, including amyloids (curli), as well as various metabolites, on the α-synuclein aggregation. In the review, we provided up-to-date information about such examples.


Asunto(s)
Amiloide , Microbioma Gastrointestinal , Enfermedad de Parkinson , Sinucleinopatías , alfa-Sinucleína , Humanos , Sinucleinopatías/metabolismo , Sinucleinopatías/microbiología , Sinucleinopatías/patología , Amiloide/metabolismo , Enfermedad de Parkinson/metabolismo , Enfermedad de Parkinson/microbiología , alfa-Sinucleína/metabolismo , Animales , Bacterias/metabolismo , Proteínas Bacterianas/metabolismo
13.
Int J Mol Sci ; 25(7)2024 Apr 04.
Artículo en Inglés | MEDLINE | ID: mdl-38612824

RESUMEN

The intention of this Special Issue is to focus on new achievements in the design, preparation, and in vitro and in vivo biological evaluation of bioactive molecules that can result in the development of natural or artificial potent compounds looking for promising pharmaceuticals and agrochemicals [...].


Asunto(s)
Agroquímicos
14.
Int J Mol Sci ; 25(7)2024 Mar 29.
Artículo en Inglés | MEDLINE | ID: mdl-38612667

RESUMEN

Knee osteoarthritis (KOA) is characterized by low-grade inflammation, loss of articular cartilage, subchondral bone remodeling, synovitis, osteophyte formation, and pain. Strong, continuous pain may indicate the need for joint replacement in patients with end-stage OA, although postoperative pain (POP) of at least a two-month duration persists in 10-40% of patients with OA. STUDY PURPOSE: The inflammation observed in joint tissues is linked to pain caused by the production of proinflammatory cytokines. Since the biosynthesis of cytokines requires energy, their production is supported by extensive metabolic conversions of carbohydrates and fatty acids, which could lead to a disruption in cellular homeostasis. Therefore, this study aimed to investigate the association between POP development and disturbances in energy metabolic conversions, focusing on carbohydrate and fatty acid metabolism. METHODS: Peripheral blood samples were collected from 26 healthy subjects and 50 patients with end-stage OA before joint replacement surgery. All implants were validated by orthopedic surgeons, and patients with OA demonstrated no inherent abnormalities to cause pain from other reasons than OA disease, such as malalignment, aseptic loosening, or excessive bleeding. Pain levels were assessed before surgery using the visual analogue scale (VAS) and neuropathic pain questionnaires, DN4 and PainDETECT. Functional activity was evaluated using the Western Ontario and McMaster Universities Osteoarthritis Index (WOMAC). Three and six months after surgery, pain indices according to a VAS of 30 mm or higher were considered. Total RNA isolated from whole blood was analyzed using quantitative real-time RT-PCR (qRT-PCR) for the expression of genes related to carbohydrate and fatty acid metabolism. Protein levels of the examined genes were measured using an ELISA in the peripheral blood mononuclear cells (PBMCs). We used qRT-PCR because it is the most sensitive and reliable method for gene expression analysis, while an ELISA was used to confirm our qRT-PCR results. KEY FINDINGS: Among the study cohort, 17 patients who reported POP demonstrated significantly higher (p < 0.05) expressions of the genes PKM2, LDH, SDH, UCP2, CPT1A, and ACLY compared to pain-free patients with KOA. Receiver-operating characteristic (ROC) curve analyses confirmed the association between these gene expressions and pain development post-arthroplasty. A principle component analysis identified the prognostic values of ACLY, CPT1A, AMPK, SDHB, Caspase 3, and IL-1ß gene expressions for POP development in the examined subjects. CONCLUSION: These findings suggest that the disturbances in energy metabolism, as observed in the PBMCs of patients with end-stage KOA before arthroplasty, may contribute to POP development. An understanding of these metabolic processes could provide insights into the pathogenesis of KOA. Additionally, our findings can be used in a clinical setting to predict POP development in end-stage patients with KOA before arthroplasty.


Asunto(s)
Artroplastia de Reemplazo , Osteoartritis de la Rodilla , Humanos , Osteoartritis de la Rodilla/cirugía , Leucocitos Mononucleares , Dolor Postoperatorio , Inflamación , Carbohidratos , Citocinas , Ácidos Grasos
15.
Int J Mol Sci ; 25(12)2024 Jun 07.
Artículo en Inglés | MEDLINE | ID: mdl-38928012

RESUMEN

In yeast Saccharomyces cerevisiae, there are two translation termination factors, eRF1 (Sup45) and eRF3 (Sup35), which are essential for viability. Previous studies have revealed that presence of nonsense mutations in these genes leads to amplification of mutant alleles (sup35-n and sup45-n), which appears to be necessary for the viability of such cells. However, the mechanism of this phenomenon remained unclear. In this study, we used RNA-Seq and proteome analysis to reveal the complete set of gene expression changes that occur during cellular adaptation to the introduction of the sup35-218 nonsense allele. Our analysis demonstrated significant changes in the transcription of genes that control the cell cycle: decreases in the expression of genes of the anaphase promoting complex APC/C (APC9, CDC23) and their activator CDC20, and increases in the expression of the transcription factor FKH1, the main cell cycle kinase CDC28, and cyclins that induce DNA biosynthesis. We propose a model according to which yeast adaptation to nonsense mutations in the translation termination factor genes occurs as a result of a delayed cell cycle progression beyond the G2-M stage, which leads to an extension of the S and G2 phases and an increase in the number of copies of the mutant sup35-n allele.


Asunto(s)
Codón sin Sentido , Regulación Fúngica de la Expresión Génica , Factores de Terminación de Péptidos , Proteínas de Saccharomyces cerevisiae , Saccharomyces cerevisiae , Saccharomyces cerevisiae/genética , Saccharomyces cerevisiae/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/metabolismo , Codón sin Sentido/genética , Factores de Terminación de Péptidos/genética , Factores de Terminación de Péptidos/metabolismo , Adaptación Fisiológica/genética , Ciclo Celular/genética
16.
Molecules ; 29(14)2024 Jul 09.
Artículo en Inglés | MEDLINE | ID: mdl-39064826

RESUMEN

In the past, polyacrylamide hydrogel was a popular choice for breast augmentation filler, and many women underwent mammoplasty with this gel. However, due to frequent complications, the use of polyacrylamide hydrogel in mammoplasty has been banned. Despite this ban, patients experiencing complications still seek medical treatment. The aim of this study was to investigate the fate of the polymer over a defined implantation period. Biopsies of breast implants were obtained from patients with 23 and 27 years of post-mammoplasty. These biopsies were meticulously purified from biological impurities and subjected to analysis using IR spectrometry, liquid chromatography-mass spectrometry, gas chromatography, and differential scanning calorimetry. The findings revealed the presence of polyacrylamide hydrogel residues, along with degradation products, within the infected material. Notably, the low-molecular-weight degradation products revealed via gas chromatography are aggressive and toxic substances capable of inducing chronic inflammation. This study sheds light on the long-term consequences of polyacrylamide hydrogel implantation, highlighting the persistence of harmful degradation products and their role in exacerbating patient complications.


Asunto(s)
Resinas Acrílicas , Inflamación , Humanos , Resinas Acrílicas/química , Femenino , Glándulas Mamarias Humanas/metabolismo , Glándulas Mamarias Humanas/patología , Implantes de Mama/efectos adversos , Adulto , Mamoplastia , Persona de Mediana Edad
17.
Br J Haematol ; 202(3): 645-656, 2023 08.
Artículo en Inglés | MEDLINE | ID: mdl-37221654

RESUMEN

Wiskott-Aldrich syndrome (WAS) is an X-linked recessive disorder caused by WAS gene mutations resulting in haematopoietic/immune cell defects. Recent studies report accelerated death of WAS platelets and lymphocytes. Data on megakaryocyte (MK) maturation, viability and their possible role in thrombocytopenia development in WAS are limited. In this study we evaluate the MK viability and morphology in untreated, romiplostim-treated WAS patients compared with normal controls. The study included 32 WAS patients and 17 healthy donors. MKs were captured from bone marrow aspirates by surface-immobilized anti-GPIIb-IIIa antibody. Viability (by phosphatidylserine [PS] externalization), distribution by maturation stages and size of MK were determined by light microscopy. MK distribution by maturation stages in patients differed from controls. 40 ± 22% of WAS MKs versus 23 ± 11% of normal MKs were at maturation stage 3 (p = 0.02), whereas 24 ± 20% in WAS and 39 ± 14% in controls had megakaryoblast morphology (p = 0.05). Romiplostim treatment changed the MK maturation stages distribution close to normal. PS-positive (PS+) MK in WAS was significantly higher (21 ± 21%) than in healthy controls (2 ± 4%, p < 0.01). WAS patients with more damaging truncating mutations and higher disease score had higher PS+ MK fraction (Spearman r = 0.6, p < 0.003). We conclude that WAS MKs have increased cell death tendency and changes in maturation pattern. Both could contribute to thrombocytopenia in WAS patients.


Asunto(s)
Trombocitopenia , Síndrome de Wiskott-Aldrich , Humanos , Megacariocitos , Síndrome de Wiskott-Aldrich/genética , Plaquetas/metabolismo , Trombocitopenia/genética , Hematopoyesis
18.
Org Biomol Chem ; 21(8): 1827-1834, 2023 Feb 22.
Artículo en Inglés | MEDLINE | ID: mdl-36751947

RESUMEN

A simple method for the synthesis of water-soluble potassium 3-[(imidazotriazin-3-yl)thio]-2-oxoquinoline-4-carboxylates was developed based on a new reversible transformation of oxindolylidene derivatives of imidazothiazolotriazine that results from their treatment with potassium hydroxide. The antiproliferative activity of the synthesized compounds was evaluated against 58 cell lines and compared with oxindolylidene derivatives of imidazothiazolotriazine. Quinoline derivatives 3 demonstrated high activity with average GI50 values of <10 µM which are comparable or higher than those of the oxindolylidene imidazothiazolotriazines. Compound 3a, with a pent-3-yl substituent at the nitrogen atom of the quinoline fragment, possessed the highest antiproliferative activity with an average GI50 value of 1.71 µM. The GI50 values of compound 3a against 52 of the 58 cell lines were <1 µM; against the remaining 6 of the 58 cell lines, they were in the range 1.21-39.2 µM.

19.
J Head Trauma Rehabil ; 38(6): E384-E393, 2023.
Artículo en Inglés | MEDLINE | ID: mdl-36854141

RESUMEN

OBJECTIVE: To directly compare the effect of incident age 68+ traumatic brain injury (TBI) on the risk of diagnosis of clinical Alzheimer's disease (AD) in the general population of older adults, and between male veterans and nonveterans; to assess how this effect changes with time since TBI. SETTING AND PARTICIPANTS: Community-dwelling traditional Medicare beneficiaries 68 years or older from the Health and Retirement Study (HRS). DESIGN: Fine-Gray models combined with inverse-probability weighting were used to identify associations between incident TBI, post-TBI duration, and TBI treatment intensity, with a diagnosis of clinical AD dementia. The study included 16 829 older adults followed over the 1991-2015 period. For analyses of veteran-specific risks, 4281 veteran males and 3093 nonveteran males were identified. Analysis of veteran females was unfeasible due to the age structure of the population. Information on occurrence(s) of TBI, and onset of AD and risk-related comorbidities was constructed from individual-level HRS-linked Medicare claim records while demographic and socioeconomic risk factors were based on the survey data. RESULTS: Later-life TBI was strongly associated with increased clinical AD risk in the full sample (pseudo-hazard ratio [HR]: 3.22; 95% confidence interval [CI]: 2.57-4.05) and in veteran/nonveteran males (HR: 5.31; CI: 3.42-7.94), especially those requiring high-intensity/duration care (HR: 1.58; CI: 1.29-1.91). Effect magnitude decreased with time following TBI (HR: 0.72: CI: 0.68-0.80). CONCLUSION: Later-life TBI was strongly associated with increased AD risk, especially in those requiring high-intensity/duration care. Effect magnitude decreased with time following TBI. Univariate analysis showed no differences in AD risk between veterans and nonveterans, while the protective effect associated with veteran status in Fine-Gray models was largely due to differences in demographics, socioeconomics, and morbidity. Future longitudinal studies incorporating diagnostic procedures and documentation quantifying lifetime TBI events are necessary to uncover pathophysiological mediating and/or moderating mechanisms between TBI and AD.


Asunto(s)
Enfermedad de Alzheimer , Lesiones Traumáticas del Encéfalo , Encefalopatía Traumática Crónica , Veteranos , Femenino , Humanos , Masculino , Anciano , Estados Unidos/epidemiología , Enfermedad de Alzheimer/epidemiología , Enfermedad de Alzheimer/complicaciones , Medicare , Lesiones Traumáticas del Encéfalo/diagnóstico , Lesiones Traumáticas del Encéfalo/epidemiología , Lesiones Traumáticas del Encéfalo/complicaciones
20.
Int J Mol Sci ; 24(18)2023 Sep 15.
Artículo en Inglés | MEDLINE | ID: mdl-37762440

RESUMEN

Many research papers describe selective hydrogenation of functional groups, such as nitro groups, carbonyl groups, or unsaturated carbon bonds to obtain fine chemicals or precursors of pharmaceuticals. Quite often, the catalyst performance is investigated in batch or continuous flow reactors without finding advantages and disadvantages of this or that regime. At the same time, the transition from batch processes to continuous flow occurs on the industrial scale. However, the batch process can be preferable for some reactions, in spite of its drawbacks. This review article aims to identify all publications that consider selective hydrogenation of functional groups in organic compounds, both in batch and continuous flow reactors, at the same reaction conditions that allow making conclusions about the benefits of one of the regimes in a particular case.


Asunto(s)
Carbono , Compuestos Orgánicos , Hidrogenación , Industrias
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