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1.
Cell ; 173(1): 181-195.e18, 2018 03 22.
Artigo em Inglês | MEDLINE | ID: mdl-29551268

RESUMO

mRNAs can fold into complex structures that regulate gene expression. Resolving such structures de novo has remained challenging and has limited our understanding of the prevalence and functions of mRNA structure. We use SHAPE-MaP experiments in living E. coli cells to derive quantitative, nucleotide-resolution structure models for 194 endogenous transcripts encompassing approximately 400 genes. Individual mRNAs have exceptionally diverse architectures, and most contain well-defined structures. Active translation destabilizes mRNA structure in cells. Nevertheless, mRNA structure remains similar between in-cell and cell-free environments, indicating broad potential for structure-mediated gene regulation. We find that the translation efficiency of endogenous genes is regulated by unfolding kinetics of structures overlapping the ribosome binding site. We discover conserved structured elements in 35% of UTRs, several of which we validate as novel protein binding motifs. RNA structure regulates every gene studied here in a meaningful way, implying that most functional structures remain to be discovered.


Assuntos
Técnicas de Amplificação de Ácido Nucleico/métodos , RNA Mensageiro/metabolismo , Algoritmos , Sítios de Ligação , Sistema Livre de Células , Primers do DNA/metabolismo , Ensaio de Desvio de Mobilidade Eletroforética , Entropia , Escherichia coli/genética , Escherichia coli/metabolismo , Proteínas de Escherichia coli/química , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Modelos Moleculares , Conformação de Ácido Nucleico , Biossíntese de Proteínas , Dobramento de RNA , RNA Mensageiro/química , Proteínas Recombinantes/biossíntese , Proteínas Recombinantes/química , Proteínas Recombinantes/isolamento & purificação , Ribossomos/química , Ribossomos/metabolismo , Regiões não Traduzidas
2.
Nature ; 625(7996): 679-684, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38267683

RESUMO

In conventional Bardeen-Cooper-Schrieffer superconductors1, electrons with opposite momenta bind into Cooper pairs due to an attractive interaction mediated by phonons in the material. Although superconductivity naturally emerges at thermal equilibrium, it can also emerge out of equilibrium when the system parameters are abruptly changed2-8. The resulting out-of-equilibrium phases are predicted to occur in real materials and ultracold fermionic atoms, but not all have yet been directly observed. Here we realize an alternative way to generate the proposed dynamical phases using cavity quantum electrodynamics (QED). Our system encodes the presence or absence of a Cooper pair in a long-lived electronic transition in 88Sr atoms coupled to an optical cavity and represents interactions between electrons as photon-mediated interactions through the cavity9,10. To fully explore the phase diagram, we manipulate the ratio between the single-particle dispersion and the interactions after a quench and perform real-time tracking of the subsequent dynamics of the superconducting order parameter using nondestructive measurements. We observe regimes in which the order parameter decays to zero (phase I)3,4, assumes a non-equilibrium steady-state value (phase II)2,3 or exhibits persistent oscillations (phase III)2,3. This opens up exciting prospects for quantum simulation, including the potential to engineer unconventional superconductors and to probe beyond mean-field effects like the spectral form factor11,12, and for increasing the coherence time for quantum sensing.

3.
Nature ; 614(7948): 564-571, 2023 02.
Artigo em Inglês | MEDLINE | ID: mdl-36755093

RESUMO

Thousands of genetic variants in protein-coding genes have been linked to disease. However, the functional impact of most variants is unknown as they occur within intrinsically disordered protein regions that have poorly defined functions1-3. Intrinsically disordered regions can mediate phase separation and the formation of biomolecular condensates, such as the nucleolus4,5. This suggests that mutations in disordered proteins may alter condensate properties and function6-8. Here we show that a subset of disease-associated variants in disordered regions alter phase separation, cause mispartitioning into the nucleolus and disrupt nucleolar function. We discover de novo frameshift variants in HMGB1 that cause brachyphalangy, polydactyly and tibial aplasia syndrome, a rare complex malformation syndrome. The frameshifts replace the intrinsically disordered acidic tail of HMGB1 with an arginine-rich basic tail. The mutant tail alters HMGB1 phase separation, enhances its partitioning into the nucleolus and causes nucleolar dysfunction. We built a catalogue of more than 200,000 variants in disordered carboxy-terminal tails and identified more than 600 frameshifts that create arginine-rich basic tails in transcription factors and other proteins. For 12 out of the 13 disease-associated variants tested, the mutation enhanced partitioning into the nucleolus, and several variants altered rRNA biogenesis. These data identify the cause of a rare complex syndrome and suggest that a large number of genetic variants may dysregulate nucleoli and other biomolecular condensates in humans.


Assuntos
Nucléolo Celular , Proteína HMGB1 , Humanos , Arginina/genética , Arginina/metabolismo , Nucléolo Celular/genética , Nucléolo Celular/metabolismo , Nucléolo Celular/patologia , Proteína HMGB1/química , Proteína HMGB1/genética , Proteína HMGB1/metabolismo , Proteínas Intrinsicamente Desordenadas/química , Proteínas Intrinsicamente Desordenadas/genética , Proteínas Intrinsicamente Desordenadas/metabolismo , Síndrome , Mutação da Fase de Leitura , Transição de Fase
4.
Nature ; 623(7988): 772-781, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37968388

RESUMO

Mouse models are a critical tool for studying human diseases, particularly developmental disorders1. However, conventional approaches for phenotyping may fail to detect subtle defects throughout the developing mouse2. Here we set out to establish single-cell RNA sequencing of the whole embryo as a scalable platform for the systematic phenotyping of mouse genetic models. We applied combinatorial indexing-based single-cell RNA sequencing3 to profile 101 embryos of 22 mutant and 4 wild-type genotypes at embryonic day 13.5, altogether profiling more than 1.6 million nuclei. The 22 mutants represent a range of anticipated phenotypic severities, from established multisystem disorders to deletions of individual regulatory regions4,5. We developed and applied several analytical frameworks for detecting differences in composition and/or gene expression across 52 cell types or trajectories. Some mutants exhibit changes in dozens of trajectories whereas others exhibit changes in only a few cell types. We also identify differences between widely used wild-type strains, compare phenotyping of gain- versus loss-of-function mutants and characterize deletions of topological associating domain boundaries. Notably, some changes are shared among mutants, suggesting that developmental pleiotropy might be 'decomposable' through further scaling of this approach. Overall, our findings show how single-cell profiling of whole embryos can enable the systematic molecular and cellular phenotypic characterization of mouse mutants with unprecedented breadth and resolution.


Assuntos
Deficiências do Desenvolvimento , Embrião de Mamíferos , Mutação , Fenótipo , Análise da Expressão Gênica de Célula Única , Animais , Camundongos , Núcleo Celular/genética , Deficiências do Desenvolvimento/genética , Deficiências do Desenvolvimento/patologia , Embrião de Mamíferos/metabolismo , Embrião de Mamíferos/patologia , Mutação com Ganho de Função , Genótipo , Mutação com Perda de Função , Modelos Genéticos , Modelos Animais de Doenças
5.
Nature ; 593(7858): 282-288, 2021 05.
Artigo em Inglês | MEDLINE | ID: mdl-33828302

RESUMO

Cancer cells characteristically consume glucose through Warburg metabolism1, a process that forms the basis of tumour imaging by positron emission tomography (PET). Tumour-infiltrating immune cells also rely on glucose, and impaired immune cell metabolism in the tumour microenvironment (TME) contributes to immune evasion by tumour cells2-4. However, whether the metabolism of immune cells is dysregulated in the TME by cell-intrinsic programs or by competition with cancer cells for limited nutrients remains unclear. Here we used PET tracers to measure the access to and uptake of glucose and glutamine by specific cell subsets in the TME. Notably, myeloid cells had the greatest capacity to take up intratumoral glucose, followed by T cells and cancer cells, across a range of cancer models. By contrast, cancer cells showed the highest uptake of glutamine. This distinct nutrient partitioning was programmed in a cell-intrinsic manner through mTORC1 signalling and the expression of genes related to the metabolism of glucose and glutamine. Inhibiting glutamine uptake enhanced glucose uptake across tumour-resident cell types, showing that glutamine metabolism suppresses glucose uptake without glucose being a limiting factor in the TME. Thus, cell-intrinsic programs drive the preferential acquisition of glucose and glutamine by immune and cancer cells, respectively. Cell-selective partitioning of these nutrients could be exploited to develop therapies and imaging strategies to enhance or monitor the metabolic programs and activities of specific cell populations in the TME.


Assuntos
Neoplasias/metabolismo , Neoplasias/patologia , Nutrientes/metabolismo , Microambiente Tumoral , Animais , Carcinoma de Células Renais/imunologia , Carcinoma de Células Renais/metabolismo , Carcinoma de Células Renais/patologia , Linhagem Celular Tumoral , Feminino , Glucose/metabolismo , Glutamina/metabolismo , Humanos , Metabolismo dos Lipídeos , Masculino , Alvo Mecanístico do Complexo 1 de Rapamicina/metabolismo , Camundongos , Células Mieloides/imunologia , Células Mieloides/metabolismo , Neoplasias/imunologia , Microambiente Tumoral/imunologia
6.
Nature ; 584(7821): 403-409, 2020 08.
Artigo em Inglês | MEDLINE | ID: mdl-32760000

RESUMO

The tuatara (Sphenodon punctatus)-the only living member of the reptilian order Rhynchocephalia (Sphenodontia), once widespread across Gondwana1,2-is an iconic species that is endemic to New Zealand2,3. A key link to the now-extinct stem reptiles (from which dinosaurs, modern reptiles, birds and mammals evolved), the tuatara provides key insights into the ancestral amniotes2,4. Here we analyse the genome of the tuatara, which-at approximately 5 Gb-is among the largest of the vertebrate genomes yet assembled. Our analyses of this genome, along with comparisons with other vertebrate genomes, reinforce the uniqueness of the tuatara. Phylogenetic analyses indicate that the tuatara lineage diverged from that of snakes and lizards around 250 million years ago. This lineage also shows moderate rates of molecular evolution, with instances of punctuated evolution. Our genome sequence analysis identifies expansions of proteins, non-protein-coding RNA families and repeat elements, the latter of which show an amalgam of reptilian and mammalian features. The sequencing of the tuatara genome provides a valuable resource for deep comparative analyses of tetrapods, as well as for tuatara biology and conservation. Our study also provides important insights into both the technical challenges and the cultural obligations that are associated with genome sequencing.


Assuntos
Evolução Molecular , Genoma/genética , Filogenia , Répteis/genética , Animais , Conservação dos Recursos Naturais/tendências , Feminino , Genética Populacional , Lagartos/genética , Masculino , Anotação de Sequência Molecular , Nova Zelândia , Caracteres Sexuais , Serpentes/genética , Sintenia
8.
Genome Res ; 32(4): 671-681, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35149543

RESUMO

One of the defining features of transposable elements (TEs) is their ability to move to new locations in the host genome. To minimize the potentially deleterious effects of de novo TE insertions, hosts have evolved several mechanisms to control TE activity, including recombination-mediated removal and epigenetic silencing; however, increasing evidence suggests that silencing of TEs is often incomplete. The crow family experienced a recent radiation of LTR retrotransposons (LTRs), offering an opportunity to gain insight into the regulatory control of young, potentially still active TEs. We quantified the abundance of TE-derived transcripts across several tissues in 15 Eurasian crows (Corvus (corone) spp.) raised under common garden conditions and find evidence for ineffective TE suppression on the female-specific W Chromosome. Using RNA-seq data, we show that ∼9.5% of all transcribed TEs had considerably greater (average, 16-fold) transcript abundance in female crows and that >85% of these female-biased TEs originated on the W Chromosome. After accounting for differences in TE density among chromosomal classes, W-linked TEs were significantly more highly expressed than TEs residing on other chromosomes, consistent with ineffective silencing on the former. Together, our results suggest that the crow W Chromosome acts as a source of transcriptionally active TEs, with possible negative fitness consequences for female birds analogous to Drosophila (an X/Y system), in which overexpression of Y-linked TEs is associated with male-specific aging and fitness loss ("toxic Y").


Assuntos
Elementos de DNA Transponíveis , Evolução Molecular , Animais , Aves , Drosophila , Epigênese Genética , Feminino , Masculino , Cromossomos Sexuais/genética
9.
Small ; 20(27): e2308148, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38290809

RESUMO

Hexagonal boron nitride (hBN) is an emerging 2D material attracting significant attention due to its superior electrical, chemical, and therapeutic properties. However, inhalation toxicity mechanisms of hBN in human lung cells are poorly understood. Here, cellular interaction and effects of hBN nanosheets is investigated in alveolar epithelial cells cultured on porous inserts and exposed under air-liquid interface conditions for 24 h. hBN is taken up by the cells as determined in a label-free manner via RAMAN-confocal microscopy, ICP-MS, TEM, and SEM-EDX. No significant (p > 0.05) effects are observed on cell membrane integrity (LDH release), epithelial barrier integrity (TEER), interleukin-8 cytokine production or reactive oxygen production at tested dose ranges (1, 5, and 10 µg cm-2). However, it is observed that an enhanced accumulation of lipid granules in cells indicating the effect of hBN on lipid metabolism. In addition, it is observed that a significant (p < 0.05) and dose-dependent (5 and 10 µg cm-2) induction of autophagy in cells after exposure to hBN, potentially associated with the downstream processing and breakdown of excess lipid granules to maintain lipid homeostasis. Indeed, lysosomal co-localization of lipid granules supporting this argument is observed. Overall, the results suggest that the continuous presence of excess intracellular lipids may provoke adverse outcomes in the lungs.


Assuntos
Células Epiteliais Alveolares , Autofagia , Compostos de Boro , Humanos , Compostos de Boro/química , Compostos de Boro/farmacologia , Autofagia/efeitos dos fármacos , Células Epiteliais Alveolares/metabolismo , Células Epiteliais Alveolares/efeitos dos fármacos , Nanoestruturas/química , Metabolismo dos Lipídeos/efeitos dos fármacos , Espécies Reativas de Oxigênio/metabolismo
10.
Small ; : e2311115, 2024 Mar 31.
Artigo em Inglês | MEDLINE | ID: mdl-38556634

RESUMO

Engineering of catalytically active inorganic nanomaterials holds promising prospects for biomedicine. Catalytically active metal oxides show applications in enhancing wound healing but have also been employed to induce cell death in photodynamic or radiation therapy. Upon introduction into a biological system, nanomaterials are exposed to complex fluids, causing interaction and adsorption of ions and proteins. While protein corona formation on nanomaterials is acknowledged, its modulation of nanomaterial catalytic efficacy is less understood. In this study, proteomic analyses and nano-analytic methodologies quantify and characterize adsorbed proteins, correlating this protein layer with metal oxide catalytic activity in vitro and in vivo. The protein corona comprises up to 280 different proteins, constituting up to 38% by weight. Enhanced complement factors and other opsonins on nanocatalyst surfaces lead to their uptake into macrophages when applied topically, localizing >99% of the nanomaterials in tissue-resident macrophages. Initially, the formation of the protein corona significantly reduces the nanocatalysts' activity, but this activity can be partially recovered in endosomal conditions due to the proteolytic degradation of the corona. Overall, the research reveals the complex relationship between physisorbed proteins and the catalytic characteristics of specific metal oxide nanoparticles, providing design parameters for optimizing nanocatalysts in complex biological environments.

11.
Basic Res Cardiol ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38483601

RESUMO

Anthracyclines are highly potent anti-cancer drugs, but their clinical use is limited by severe cardiotoxic side effects. The impact of anthracycline-induced cardiotoxicity (AIC) on left ventricular (LV) microarchitecture and diffusion properties remains unknown. This study sought to characterize AIC by cardiovascular magnetic resonance diffusion tensor imaging (DTI). Mice were treated with Doxorubicin (DOX; n = 16) for induction of AIC or saline as corresponding control (n = 15). Cardiac function was assessed via echocardiography at the end of the study period. Whole hearts (n = 8 per group) were scanned ex vivo by high-resolution DTI at 7 T. Results were correlated with histopathology and mass spectrometry imaging. Mice with AIC demonstrated systolic dysfunction (LVEF 52 ± 3% vs. 43 ± 6%, P < 0.001), impaired global longitudinal strain (-19.6 ± 2.0% vs. -16.6 ± 3.0%, P < 0.01), and cardiac atrophy (LV mass index [mg/mm], 4.3 ± 0.1 vs. 3.6 ± 0.2, P < 0.01). Regional sheetlet angles were significantly lower in AIC, whereas helix angle and relative helicity remained unchanged. In AIC, fractional anisotropy was increased (0.12 ± 0.01 vs. 0.14 ± 0.02, P < 0.05). DOX-treated mice displayed higher planar and less spherical anisotropy (CPlanar 0.07 ± 0.01 vs. 0.09 ± 0.01, P < 0.01; CSpherical 0.89 ± 0.01 vs. 0.87 ± 0.02, P < 0.05). CPlanar and CSpherical yielded good discriminatory power to distinguish between mice with and without AIC (c-index 0.91 and 0.84, respectively, P for both < 0.05). AIC is associated with regional changes in sheetlet angle but no major abnormalities of global LV microarchitecture. The geometric shape of the diffusion tensor is altered in AIC. DTI may provide a new tool for myocardial characterization in patients with AIC, which warrants future clinical studies to evaluate its diagnostic utility.

12.
Mol Ecol ; : e17382, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38856653

RESUMO

RNA sequencing (RNAseq) methodology has experienced a burst of technological developments in the last decade, which has opened up opportunities for studying the mechanisms of adaptation to environmental factors at both the organismal and cellular level. Selecting the most suitable experimental approach for specific research questions and model systems can, however, be a challenge and researchers in ecology and evolution are commonly faced with the choice of whether to study gene expression variation in whole bodies, specific tissues, and/or single cells. A wide range of sometimes polarised opinions exists over which approach is best. Here, we highlight the advantages and disadvantages of each of these approaches to provide a guide to help researchers make informed decisions and maximise the power of their study. Using illustrative examples of various ecological and evolutionary research questions, we guide the readers through the different RNAseq approaches and help them identify the most suitable design for their own projects.

13.
Microb Pathog ; 190: 106605, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38428470

RESUMO

The objective of the present study was to evaluate the impacts of trichothecenes (Fusarium sporotrichioides) for dairy calves on animal growth, oxidative and inflammatory responses in the presence or absence of essential oils. Twelve calves weaned at 70 days of age were divided into 2 groups: T-C (control) and T-EO (essential oils - oregano, thyme, basil and rosemary) in the period of 40 days consuming ration contaminated by trichothecenes (500 ppb). The animals in the T-EO group received a mixture of EOs via feed at a dosage of 0.75 mL per/kg of feed. Blood collections were performed on days 1, 20 and 40 for hematological and biochemical analyses; the fecal score was performed every 2 days on a scale of 1-5 and clinical examinations were performed 3 times during the experiment period. The animals were weighed at the beginning and at the end of the experiment; euthanasia of two calves per group for macroscopic and microscopic evaluation of several tissues (spleen, liver, duodenum, jejunum, ilium, cecum and colon) was performed at the end of the experiment. The calves in the T-EO group had a tendency (P = 0.07) of higher body weight when compared to the T-C. Treatment effect and treatment vs day interaction was detected for leukocytes and granulocytes variables, demonstrating a higher count of these cells in the T-EO group on both days (20 and 40), and the same behavior occurred for the distribution amplitude of erythrocytes (RDW). The enzymes alanine transferase (ALT), aspartate transferase (AST) and gamma glutamyl-transferase (GGT) showed higher serum activity in the T-C group (days 20 and 40). The levels of thiobarbituric acid reactive substances (TBARS) were lower in the serum of animals in the T-EO group. For calves in the T-EO group, glutathione S-transferase activity was higher in serum. Haptoglobulin and C-reactive protein levels were lower on days 20 and 40 in T-EO animals when compared to the T-C group. In the macroscopic and microscopic evaluations, which were collected at the end of the experiment after slaughtering the animals, liver and intestine did not show changes for the animals in the T-EO group, unlike the animals in the T-C group, which had moderately firm diffuse consistency of the liver and edema in the mesentery, as well as oxidative stress in tissues (liver, duodenum, jejunum, ileum, cecum and colon). The results concluded that the consumption of a mixture of EOs (essential oils - oregano, thyme, basil and rosemary) minimized the negative effects caused by trichothecenes in dairy calves, thus being an alternative to improving the immunological and antioxidant condition, as well as a possible adsorbent alternative.


Assuntos
Ração Animal , Fezes , Óleos Voláteis , Estresse Oxidativo , Tricotecenos , Animais , Bovinos , Estresse Oxidativo/efeitos dos fármacos , Óleos Voláteis/farmacologia , Inflamação/metabolismo , Doenças dos Bovinos/metabolismo , Doenças dos Bovinos/tratamento farmacológico , Peso Corporal/efeitos dos fármacos , Fígado/patologia , Fígado/metabolismo , Fígado/efeitos dos fármacos
14.
Mol Psychiatry ; 2023 Nov 29.
Artigo em Inglês | MEDLINE | ID: mdl-38030819

RESUMO

Mutations in the PQBP1 gene (polyglutamine-binding protein-1) are responsible for a syndromic X-linked form of neurodevelopmental disorder (XL-NDD) with intellectual disability (ID), named Renpenning syndrome. PQBP1 encodes a protein involved in transcriptional and post-transcriptional regulation of gene expression. To investigate the consequences of PQBP1 loss, we used RNA interference to knock-down (KD) PQBP1 in human neural stem cells (hNSC). We observed a decrease of cell proliferation, as well as the deregulation of the expression of 58 genes, comprising genes encoding proteins associated with neurodegenerative diseases, playing a role in mRNA regulation or involved in innate immunity. We also observed an enrichment of genes involved in other forms of NDD (CELF2, APC2, etc). In particular, we identified an increase of a non-canonical isoform of another XL-NDD gene, UPF3B, an actor of nonsense mRNA mediated decay (NMD). This isoform encodes a shorter protein (UPF3B_S) deprived from the domains binding NMD effectors, however no notable change in NMD was observed after PQBP1-KD in fibroblasts containing a premature termination codon. We showed that short non-canonical and long canonical UPF3B isoforms have different interactomes, suggesting they could play distinct roles. The link between PQBP1 loss and increase of UPF3B_S expression was confirmed in mRNA obtained from patients with pathogenic variants in PQBP1, particularly pronounced for truncating variants and missense variants located in the C-terminal domain. We therefore used it as a molecular marker of Renpenning syndrome, to test the pathogenicity of variants of uncertain clinical significance identified in PQPB1 in individuals with NDD, using patient blood mRNA and HeLa cells expressing wild-type or mutant PQBP1 cDNA. We showed that these different approaches were efficient to prove a functional effect of variants in the C-terminal domain of the protein. In conclusion, our study provided information on the pathological mechanisms involved in Renpenning syndrome, but also allowed the identification of a biomarker of PQBP1 deficiency useful to test variant effect.

15.
Transfusion ; 64(4): 572-577, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38380832

RESUMO

INTRODUCTION: Sanquin donor medicine department is informed when donations or their components are rejected. This can occur isolated or frequently. It is undesirable because the donations cannot be used and there may be an underlying medical cause. Based on regional approaches, a uniform procedure was developed. METHODS: Information about whole blood, plasma- plateletpheresis donations from which one or more components were rejected for filtration time (>2 h), hemolysis or clots were extracted from blood bank information system. After rejection of two successive components or donations or total ≥3 the donor is contacted. Depending on the medical history and investigation by the family doctor, the donor carrier is re-evaluated. We looked for the causes of the discarded products and performed a survey among blood services regarding polices with discarded products. RESULTS: One or more components from 1742 of about 2.2 million successful donations (0.08%) were rejected. The highest percentage of rejection was seen in plateletpheresis (1.5%), all for clots. No underlying medical causes were found. 24 whole blood donors were found to have sickle cell trait (SCT) and were permanently deferred. The policies for follow-up after discarded products or acceptance of SCT donors vary between the 16 blood banks. Six organizations do not follow-up donors and seven accept SCT for blood or plasma donation. CONCLUSION: Informing donors with repeated discarded products avoids the non-use of donations. Causes of repeated discarded products can be found by follow-up of donors. The results of the survey indicate a large discrepancy in policies applied worldwide.


Assuntos
Hemólise , Plaquetoferese , Humanos , Seguimentos , Doadores de Sangue , Bancos de Sangue
16.
Nature ; 555(7694): 61-66, 2018 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-29466338

RESUMO

Molecular communication in biology is mediated by protein interactions. According to the current paradigm, the specificity and affinity required for these interactions are encoded in the precise complementarity of binding interfaces. Even proteins that are disordered under physiological conditions or that contain large unstructured regions commonly interact with well-structured binding sites on other biomolecules. Here we demonstrate the existence of an unexpected interaction mechanism: the two intrinsically disordered human proteins histone H1 and its nuclear chaperone prothymosin-α associate in a complex with picomolar affinity, but fully retain their structural disorder, long-range flexibility and highly dynamic character. On the basis of closely integrated experiments and molecular simulations, we show that the interaction can be explained by the large opposite net charge of the two proteins, without requiring defined binding sites or interactions between specific individual residues. Proteome-wide sequence analysis suggests that this interaction mechanism may be abundant in eukaryotes.


Assuntos
Histonas/química , Histonas/metabolismo , Proteínas Intrinsicamente Desordenadas/química , Proteínas Intrinsicamente Desordenadas/metabolismo , Precursores de Proteínas/química , Precursores de Proteínas/metabolismo , Timosina/análogos & derivados , Sítios de Ligação , Humanos , Ligação Proteica , Eletricidade Estática , Timosina/química , Timosina/metabolismo
17.
Dig Dis Sci ; 69(3): 749-765, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38217680

RESUMO

BACKGROUND: Crohn's disease (CD) and ulcerative colitis (UC) are inflammatory bowel diseases (IBD) that contributes in part to irreversible bowel damage and long-term complications, reduced quality of life, invalidity, and economic burden. Suboptimal control of IBD is associated with higher healthcare resource utilization (HCRU), impaired quality of life (QoL), and reduced work productivity. AIMS: The IBD-PODCAST study aimed to assess the proportion of IBD patients with suboptimal control and its associated impact. METHODS: IBD-PODCAST is a cross-sectional, multicenter study that aimed to characterize the CD and UC population with optimal or suboptimal control according to the STRIDE-II criteria and patient- and physician-reported measures. Here we present the results of the Spanish cohort (n = 396). RESULTS: A total of 104/196 (53.1%) CD and 83/200 (41.5%) UC patients were found to have suboptimal disease control. Long-term treatment targets according to STRIDE-II were applied in 172 (87.8%) CD and 181 (90.5%) UC patients. 125 of 172 (72.7%) CD and 74 of 181 (40.9%) UC patients were currently treated with targeted immunomodulators. Patients with CD and UC and suboptimal disease control showed impaired QoL, higher HCRU and direct costs, and also loss of work productivity compared to those with optimal control. CONCLUSION: Despite a high rate of targeted immunomodulator therapy, a substantial proportion of IBD patients show suboptimal disease control according to the STRIDE II criteria. Those patients with suboptimal disease control exhibit impaired QoL, less work productivity, and higher HCRU, suggesting that there is considerable need for better treatment approaches in IBD.


Assuntos
Colite Ulcerativa , Doença de Crohn , Doenças Inflamatórias Intestinais , Humanos , Qualidade de Vida , Espanha/epidemiologia , Estudos Transversais , Doenças Inflamatórias Intestinais/tratamento farmacológico , Doenças Inflamatórias Intestinais/epidemiologia , Doença de Crohn/diagnóstico , Doença de Crohn/tratamento farmacológico , Colite Ulcerativa/diagnóstico , Colite Ulcerativa/tratamento farmacológico , Fatores Imunológicos/uso terapêutico
18.
Biochemistry (Mosc) ; 89(3): 574-582, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38648774

RESUMO

Rabies is a zoonotic disease with high lethality. Most human deaths are associated with the bites received from dogs and cats. Vaccination is the most effective method of preventing rabies disease in both animals and humans. In this study, the ability of an adjuvant based on recombinant Salmonella typhimurium flagellin to increase protective activity of the inactivated rabies vaccine in mice was evaluated. A series of inactivated dry culture vaccine for dogs and cats "Rabikan" (strain Shchelkovo-51) with addition of an adjuvant at various dilutions were used. The control preparation was a similar series of inactivated dry culture vaccine without an adjuvant. Protective activity of the vaccine preparations was evaluated by the NIH potency test, which is the most widely used and internationally recommended method for testing effectiveness of the inactivated rabies vaccines. The value of specific activity of the tested rabies vaccine when co-administered with the adjuvant was significantly higher (48.69 IU/ml) than that of the vaccine without the adjuvant (3.75 IU/ml). Thus, recombinant flagellin could be considered as an effective adjuvant in the composition of future vaccine preparations against rabies virus.


Assuntos
Adjuvantes Imunológicos , Flagelina , Vacina Antirrábica , Raiva , Vacinas de Produtos Inativados , Vacina Antirrábica/imunologia , Vacina Antirrábica/administração & dosagem , Animais , Flagelina/imunologia , Camundongos , Raiva/prevenção & controle , Raiva/imunologia , Vacinas de Produtos Inativados/imunologia , Cães , Vírus da Raiva/imunologia , Salmonella typhimurium/imunologia , Feminino , Gatos
19.
Med Educ ; 58(5): 544-555, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38011865

RESUMO

INTRODUCTION: Medical educators aim to understand why students differ in performance and stress. While performance and stress are associated with student demographics, school factors and aspects of self-regulated learning (SRL), it remains unclear how these elements interact within individuals. This multi-cohort study identified SRL profiles among medical students and explored their associations with performance and stress. Additionally, we examined the identified profiles' associations with gender, migration status and assessment policy. METHODS: We used latent profile analysis (LPA) to identify profiles on Motivated Strategies for Learning Questionnaire (MSLQ) scores of six cohorts (2014-2019) of Year 1, first semester medical students (n = 1894) in a Dutch medical school. We used nine MSLQ subscales that measure test anxiety (TA), self-efficacy, deep learning, resource management and value. The university's assessment policy varied, demanding students to obtain 100% or 75% of Year 1 credits to remain enrolled. We defined optimal performance as obtaining all credits at the end of Year 1. Two cohorts completed the Perceived Stress Scale (PSS-14, n = 409) in the 2nd semester. RESULTS: We identified three distinct student profiles: 693/1894(36.6%) were classified as TAhighSRLhigh, 661/1894(34.9%) as TAlowSRLhigh and 540/1894(28.5%) as TAmoderateSRLlow. Females were more likely to belong to TAhighSRLhigh profiles compared to males (effect size [ES] Cramer's V = .13, small). Migration background was not associated with these profiles. The TAhighSRLhigh profile was more prevalent under the 100% assessment policy (ES Cramer's V = .10, negligible). TAlowSRLhigh students demonstrated lower stress levels (PSS = 23.9 out of 56) compared to TAhighSRLhigh students (PSS = 28.7, ES Cohen's d = .62, medium) and TAmoderateSRLlow students (PSS = 28.2, ES Cohen's d = .51, medium). Performance differed among the three profiles (ES Cramer's V = .16, small): 82.5% optimal performance in the TAlowSRLhigh, 71.9% in the TAhighSRLhigh and 65.2% in the TAmoderateSRLlow profile. DISCUSSION: Three distinct SRL student profiles associated with gender, academic performance and perceived stress were identified. Test anxiety had additional value in distinguishing subgroups with differential academic performance and stress. These profiles may aid educators to inform personalised support strategies for novice learners.


Assuntos
Testes Psicológicos , Autorrelato , Estudantes de Medicina , Ansiedade aos Exames , Masculino , Feminino , Humanos , Estudos de Coortes , Motivação , Inquéritos e Questionários
20.
Child Care Health Dev ; 50(1): e13196, 2024 01.
Artigo em Inglês | MEDLINE | ID: mdl-37965880

RESUMO

BACKGROUND: This cross-sectional study aimed to investigate the association between negative mental health conditions and demographic characteristics, socioeconomic background and health-related parameters in both Hong Kong's primary and secondary school students. METHODS: A self-administrated survey was conducted and investigated the prevalence of negative mental health conditions (psychological stress, depression and suicidality) in students from 30 primary schools and 25 secondary schools in Hong Kong in 2017. The Kessler Psychological Distress Scale (K6) was chosen as the instrument to evaluate non-specific psychological distress. Depression was evaluated using the prolonged feeling of despair as a proxy. Suicidality was measured by four questions on whether they had ever intentionally injured themselves, seriously considered attempting suicide, planned how they would attempt suicide and had attempted suicide. Multiple logistic regression models examined the explanatory factors' association with mental health conditions after adjusting for confounding, using the enter method. RESULTS: A total of 4884 responses were collected. It is found that both very high and low parent expectations were risk factors for multiple conditions, namely suicidality and psychological distress among primary school students, and psychological distress among secondary school students. As for primary school students, the experience of being bullied was a significant risk factor for all conditions. A significant association was found between having one's own bedroom and suicidality amongst primary school students; whilst having three close friends or more and higher life satisfaction levels were significantly associated with a lower risk of negative mental health conditions among secondary school students. CONCLUSIONS: It was found that having one's own bedroom was a risk factor for suicidality among primary school student. Parents should be alert to the risky behaviours of children, have more involvement in children's daily life and build a supportive and caring family environment for children. For secondary school students, as the importance of friends is greatly increased, teachers should encourage students to engage in extra-curricular activities in school.


Assuntos
Saúde Mental , Tentativa de Suicídio , Criança , Humanos , Hong Kong/epidemiologia , Estudos Transversais , Tentativa de Suicídio/psicologia , Ideação Suicida
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