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1.
Cell ; 162(4): 872-84, 2015 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-26276635

RESUMO

To study the function of Rli1/ABCE1 in vivo, we used ribosome profiling and biochemistry to characterize its contribution to ribosome recycling. When Rli1 levels were diminished, 80S ribosomes accumulated both at stop codons and in the adjoining 3'UTRs of most mRNAs. Frequently, these ribosomes reinitiated translation without the need for a canonical start codon, as small peptide products predicted by 3'UTR ribosome occupancy in all three reading frames were confirmed by western analysis and mass spectrometry. Eliminating the ribosome-rescue factor Dom34 dramatically increased 3'UTR ribosome occupancy in Rli1 depleted cells, indicating that Dom34 clears the bulk of unrecycled ribosomes. Thus, Rli1 is crucial for ribosome recycling in vivo and controls ribosome homeostasis. 3'UTR translation occurs in wild-type cells as well, and observations of elevated 3'UTR ribosomes during stress suggest that modulating recycling and reinitiation is involved in responding to environmental changes.


Assuntos
Regiões 3' não Traduzidas , Transportadores de Cassetes de Ligação de ATP/metabolismo , Biossíntese de Proteínas , Ribossomos/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Sequência de Aminoácidos , Sequência de Bases , Códon de Terminação , Histidina/metabolismo , Dados de Sequência Molecular
2.
Mol Cell ; 71(5): 761-774.e5, 2018 09 06.
Artigo em Inglês | MEDLINE | ID: mdl-30146315

RESUMO

The recycling of ribosomal subunits after translation termination is critical for efficient gene expression. Tma64 (eIF2D), Tma20 (MCT-1), and Tma22 (DENR) function as 40S recycling factors in vitro, but it is unknown whether they perform this function in vivo. Ribosome profiling of tma deletion strains revealed 80S ribosomes queued behind the stop codon, consistent with a block in 40S recycling. We found that unrecycled ribosomes could reinitiate translation at AUG codons in the 3' UTR, as evidenced by peaks in the footprint data and 3' UTR reporter analysis. In vitro translation experiments using reporter mRNAs containing upstream open reading frames (uORFs) further established that reinitiation increased in the absence of these proteins. In some cases, 40S ribosomes appeared to rejoin with 60S subunits and undergo an 80S reinitiation process in 3' UTRs. These results support a crucial role for Tma64, Tma20, and Tma22 in recycling 40S ribosomal subunits at stop codons and translation reinitiation.


Assuntos
Biossíntese de Proteínas/efeitos dos fármacos , Subunidades Ribossômicas Menores de Eucariotos/genética , Ribossomos/metabolismo , Proteínas de Saccharomyces cerevisiae/genética , Regiões 3' não Traduzidas/genética , Códon de Terminação/genética , Escherichia coli/genética , Fases de Leitura Aberta/genética , Iniciação Traducional da Cadeia Peptídica/genética , RNA Mensageiro/genética , Saccharomyces cerevisiae/genética
3.
Bioinformatics ; 40(1)2024 01 02.
Artigo em Inglês | MEDLINE | ID: mdl-38058211

RESUMO

MOTIVATION: Pediatric kidney disease is a widespread, progressive condition that severely impacts growth and development of children. Chronic kidney disease is often more insidious in children than in adults, usually requiring a renal biopsy for diagnosis. Biopsy evaluation requires copious examination by trained pathologists, which can be tedious and prone to human error. In this study, we propose an artificial intelligence (AI) method to assist pathologists in accurate segmentation and classification of pediatric kidney structures, named as AI-based Pediatric Kidney Diagnosis (APKD). RESULTS: We collected 2935 pediatric patients diagnosed with kidney disease for the development of APKD. The dataset comprised 93 932 histological structures annotated manually by three skilled nephropathologists. APKD scored an average accuracy of 94% for each kidney structure category, including 99% in the glomerulus. We found strong correlation between the model and manual detection in detected glomeruli (Spearman correlation coefficient r = 0.98, P < .001; intraclass correlation coefficient ICC = 0.98, 95% CI = 0.96-0.98). Compared to manual detection, APKD was approximately 5.5 times faster in segmenting glomeruli. Finally, we show how the pathological features extracted by APKD can identify focal abnormalities of the glomerular capillary wall to aid in the early diagnosis of pediatric kidney disease. AVAILABILITY AND IMPLEMENTATION: https://github.com/ChunyueFeng/Kidney-DataSet.


Assuntos
Inteligência Artificial , Insuficiência Renal Crônica , Adulto , Humanos , Criança , Rim/diagnóstico por imagem , Rim/patologia , Insuficiência Renal Crônica/patologia
4.
Blood ; 142(25): 2146-2158, 2023 12 21.
Artigo em Inglês | MEDLINE | ID: mdl-37738626

RESUMO

ABSTRACT: Deleterious germ line RUNX1 variants cause the autosomal dominant familial platelet disorder with associated myeloid malignancy (FPDMM), characterized by thrombocytopenia, platelet dysfunction, and a predisposition to hematologic malignancies (HMs). We launched a FPDMM natural history study and, from January 2019 to December 2021, enrolled 214 participants, including 111 patients with 39 different RUNX1 variants from 45 unrelated families. Seventy of 77 patients had thrombocytopenia, 18 of 18 had abnormal platelet aggregometry, 16 of 35 had decreased platelet dense granules, and 28 of 55 had abnormal bleeding scores. Nonmalignant bone marrows showed increased numbers of megakaryocytes in 12 of 55 patients, dysmegakaryopoiesis in 42 of 55, and reduced cellularity for age in 30 of 55 adult and 17 of 21 pediatric cases. Of 111 patients, 19 were diagnosed with HMs, including myelodysplastic syndrome, acute myeloid leukemia, chronic myelomonocytic leukemia, acute lymphoblastic leukemia, and smoldering myeloma. Of those 19, 18 were relapsed or refractory to upfront therapy and referred for stem cell transplantation. In addition, 28 of 45 families had at least 1 member with HM. Moreover, 42 of 45 patients had allergic symptoms, and 24 of 30 had gastrointestinal (GI) symptoms. Our results highlight the importance of a multidisciplinary approach, early malignancy detection, and wider awareness of inherited disorders. This actively accruing, longitudinal study will genotype and phenotype more patients with FPDMM, which may lead to a better understanding of the disease pathogenesis and clinical course, which may then inform preventive and therapeutic interventions. This trial was registered at www.clinicaltrials.gov as #NCT03854318.


Assuntos
Neoplasias Hematológicas , Leucemia Mieloide Aguda , Transtornos Mieloproliferativos , Trombocitopenia , Adulto , Humanos , Criança , Subunidade alfa 2 de Fator de Ligação ao Core/genética , Estudos Longitudinais , Leucemia Mieloide Aguda/genética , Leucemia Mieloide Aguda/terapia , Leucemia Mieloide Aguda/complicações , Trombocitopenia/genética , Transtornos Mieloproliferativos/complicações , Neoplasias Hematológicas/genética , Neoplasias Hematológicas/terapia , Neoplasias Hematológicas/complicações
5.
Blood ; 141(20): 2520-2536, 2023 05 18.
Artigo em Inglês | MEDLINE | ID: mdl-36735910

RESUMO

Metabolic programs contribute to hematopoietic stem and progenitor cell (HSPC) fate, but it is not known whether the metabolic regulation of protein synthesis controls HSPC differentiation. Here, we show that SLC7A1/cationic amino acid transporter 1-dependent arginine uptake and its catabolism to the polyamine spermidine control human erythroid specification of HSPCs via the activation of the eukaryotic translation initiation factor 5A (eIF5A). eIF5A activity is dependent on its hypusination, a posttranslational modification resulting from the conjugation of the aminobutyl moiety of spermidine to lysine. Notably, attenuation of hypusine synthesis in erythroid progenitors, by the inhibition of deoxyhypusine synthase, abrogates erythropoiesis but not myeloid cell differentiation. Proteomic profiling reveals mitochondrial translation to be a critical target of hypusinated eIF5A, and accordingly, progenitors with decreased hypusine activity exhibit diminished oxidative phosphorylation. This affected pathway is critical for eIF5A-regulated erythropoiesis, as interventions augmenting mitochondrial function partially rescue human erythropoiesis under conditions of attenuated hypusination. Levels of mitochondrial ribosomal proteins (RPs) were especially sensitive to the loss of hypusine, and we find that the ineffective erythropoiesis linked to haploinsufficiency of RPS14 in chromosome 5q deletions in myelodysplastic syndrome is associated with a diminished pool of hypusinated eIF5A. Moreover, patients with RPL11-haploinsufficient Diamond-Blackfan anemia as well as CD34+ progenitors with downregulated RPL11 exhibit a markedly decreased hypusination in erythroid progenitors, concomitant with a loss of mitochondrial metabolism. Thus, eIF5A-dependent protein synthesis regulates human erythropoiesis, and our data reveal a novel role for RPs in controlling eIF5A hypusination in HSPCs, synchronizing mitochondrial metabolism with erythroid differentiation.


Assuntos
Proteômica , Espermidina , Humanos , Espermidina/metabolismo , Fatores de Iniciação de Peptídeos/genética , Diferenciação Celular , Fator de Iniciação de Tradução Eucariótico 5A
6.
Mol Ther ; 32(4): 935-951, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38327047

RESUMO

Angelman syndrome (AS), an early-onset neurodevelopmental disorder characterized by abnormal gait, intellectual disabilities, and seizures, occurs when the maternal allele of the UBE3A gene is disrupted, since the paternal allele is silenced in neurons by the UBE3A antisense (UBE3A-AS) transcript. Given the importance of early treatment, we hypothesized that prenatal delivery of an antisense oligonucleotide (ASO) would downregulate the murine Ube3a-AS, resulting in increased UBE3A protein and functional rescue. Using a mouse model with a Ube3a-YFP allele that reports on-target ASO activity, we found that in utero, intracranial (IC) injection of the ASO resulted in dose-dependent activation of paternal Ube3a, with broad biodistribution. Accordingly, in utero injection of the ASO in a mouse model of AS also resulted in successful restoration of UBE3A and phenotypic improvements in treated mice on the accelerating rotarod and fear conditioning. Strikingly, even intra-amniotic (IA) injection resulted in systemic biodistribution and high levels of UBE3A reactivation throughout the brain. These findings offer a novel strategy for early treatment of AS using an ASO, with two potential routes of administration in the prenatal window. Beyond AS, successful delivery of a therapeutic ASO into neurons has implications for a clinically feasible prenatal treatment for numerous neurodevelopmental disorders.


Assuntos
Síndrome de Angelman , Animais , Camundongos , Síndrome de Angelman/terapia , Síndrome de Angelman/tratamento farmacológico , Oligonucleotídeos Antissenso/uso terapêutico , Distribuição Tecidual , Encéfalo/metabolismo , Fenótipo , Ubiquitina-Proteína Ligases/genética , Modelos Animais de Doenças
7.
Antimicrob Agents Chemother ; 68(1): e0099223, 2024 Jan 10.
Artigo em Inglês | MEDLINE | ID: mdl-38059634

RESUMO

Vancomycin is the first-line agent to treat pulmonary infections caused by methicillin-resistant Staphylococcus aureus (MRSA) in people with cystic fibrosis (PwCF). However, there is no consensus on vancomycin initial dosing in this population among health institutions, and there is a large variability in initial dosing across the United States. In this study, we characterized the pharmacokinetics (PK) of vancomycin in PwCF using a population PK approach. The clinical PK data to develop the population PK model were obtained from vancomycin therapeutic monitoring data from PwCF undergoing treatment for infections due to MRSA. The population PK model was then used to perform comprehensive Monte Carlo simulations to evaluate the probability of target attainment (PTA) of 12 different initial dosing scenarios. The area under the curve to minimum inhibitory concentration (MIC) ratio ≥400 mg*h/L and <650 mg*h/L were used as efficacy and toxicity targets for PTA analysis. A total of 181 vancomycin plasma concentrations were included in the analysis. A one-compartment model with first-order elimination best described the data. Weight significantly influenced the vancomycin PK (P < 0.05). In the final model, clearance was estimated as 5.52 L/h/70 kg, and the volume of distribution was 31.5 L/70 kg. The PTA analysis showed that at MIC = 1 µg/mL, doses 1,500 q8h and 2,000 q12h showed the highest %PTA in achieving both efficacy and toxicity targets. The PTA results from this study may potentially inform the initial dosing regimens of vancomycin to treat pulmonary infections due to MRSA in PwCF.


Assuntos
Fibrose Cística , Staphylococcus aureus Resistente à Meticilina , Adulto , Humanos , Vancomicina/farmacologia , Antibacterianos/farmacologia , Fibrose Cística/tratamento farmacológico , Testes de Sensibilidade Microbiana , Método de Monte Carlo
8.
Br J Haematol ; 204(5): 2077-2085, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38462764

RESUMO

Diamond-Blackfan anaemia (DBA) is a rare, inherited bone marrow failure syndrome with a ribosomal defect causing slowed globin chain production with normal haem synthesis, causing an overabundance of reactive iron/haem and erythroid-specific cellular toxicity. Eltrombopag, a non-peptide thrombopoietin receptor agonist, is a potent intracellular iron chelator and induced a robust durable response in an RPS19-mutated DBA patient on another trial. We hypothesized eltrombopag would improve RBC production in DBA patients. We conducted a single-centre, single-arm pilot study (NCT04269889) assessing safety and erythroid response of 6 months of daily, fixed-dose eltrombopag for DBA patients. Fifteen transfusion-dependent (every 3-5 weeks) patients (median age 18 [range 2-56]) were treated. One responder had sustained haemoglobin improvement and >50% reduction in RBC transfusion frequency. Of note, 7/15 (41%) patients required dose reductions or sustained discontinuation of eltrombopag due to asymptomatic thrombocytosis. Despite the low response rate, eltrombopag has now improved erythropoiesis in several patients with DBA with a favourable safety profile. Dosing restrictions due to thrombocytosis may cause insufficient iron chelation to decrease haem production and improve anaemia in most patients. Future work will focus on erythropoiesis dynamics in patients and use of haem synthesis inhibitors without an impact on other haematopoietic lineages.


Assuntos
Anemia de Diamond-Blackfan , Benzoatos , Hidrazinas , Pirazóis , Humanos , Anemia de Diamond-Blackfan/tratamento farmacológico , Pirazóis/uso terapêutico , Hidrazinas/uso terapêutico , Hidrazinas/administração & dosagem , Hidrazinas/efeitos adversos , Benzoatos/uso terapêutico , Benzoatos/administração & dosagem , Benzoatos/efeitos adversos , Adulto , Masculino , Feminino , Criança , Adolescente , Pessoa de Meia-Idade , Adulto Jovem , Pré-Escolar , Projetos Piloto , Resultado do Tratamento , Receptores de Trombopoetina/agonistas , Recidiva , Eritropoese/efeitos dos fármacos
9.
Blood ; 139(23): 3439-3449, 2022 06 09.
Artigo em Inglês | MEDLINE | ID: mdl-35349664

RESUMO

We follow a patient with Diamond-Blackfan anemia (DBA) mosaic for a pathogenic RPS19 haploinsufficiency mutation with persistent transfusion-dependent anemia. Her anemia remitted on eltrombopag (EPAG), but surprisingly, mosaicism was unchanged, suggesting that both mutant and normal cells responded. When EPAG was withheld, her anemia returned. In addition to expanding hematopoietic stem/progenitor cells, EPAG aggressively chelates iron. Because DBA anemia, at least in part, results from excessive intracellular heme leading to ferroptotic cell death, we hypothesized that the excess heme accumulating in ribosomal protein-deficient erythroid precursors inhibited the growth of adjacent genetically normal precursors, and that the efficacy of EPAG reflected its ability to chelate iron, limit heme synthesis, and thus limit toxicity in both mutant and normal cells. To test this, we studied Rpl11 haploinsufficient (DBA) mice and mice chimeric for the cytoplasmic heme export protein, FLVCR. Flvcr1-deleted mice have severe anemia, resembling DBA. Mice transplanted with ratios of DBA to wild-type marrow cells of 50:50 are anemic, like our DBA patient. In contrast, mice transplanted with Flvcr1-deleted (unable to export heme) and wild-type marrow cells at ratios of 50:50 or 80:20 have normal numbers of red cells. Additional studies suggest that heme exported from DBA erythroid cells might impede the nurse cell function of central macrophages of erythroblastic islands to impair the maturation of genetically normal coadherent erythroid cells. These findings have implications for the gene therapy of DBA and may provide insights into why del(5q) myelodysplastic syndrome patients are anemic despite being mosaic for chromosome 5q deletion and loss of RPS14.


Assuntos
Anemia de Diamond-Blackfan , Anemia , Anemia/patologia , Anemia de Diamond-Blackfan/metabolismo , Animais , Deleção Cromossômica , Células Eritroides/metabolismo , Eritropoese/genética , Feminino , Heme/metabolismo , Humanos , Ferro/metabolismo , Camundongos , Proteínas Ribossômicas/genética , Proteínas Ribossômicas/metabolismo
10.
Chemistry ; 30(24): e202400377, 2024 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-38403857

RESUMO

The atom-transfer radical addition (ATRA) reaction simultaneously forges carbon-carbon and carbon-halogen bonds. However, frequently-used photosensitizers such as precious transition metal complexes, or organic dyes have limitations in terms of their potential toxicity and recyclability. Three ß-ketoenamine-linked covalent organic frameworks (COFs) from 1,3,5-triformylphloroglucinol and 1,4-phenylenediamines with variable transient photocurrent and photocatalytic activity have been prepared. A COF bearing electron-deficient Cl atoms displayed the highest photocatalytic activity toward the ATRA reaction of polyhalogenated alkanes to give halogenated olefins under visible light at room temperature. This heterogeneous photocatalyst exhibited good functional group tolerance and could be recycled without significant loss of activity.

11.
Langmuir ; 40(19): 9945-9956, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38691534

RESUMO

Intermittent oil-water wetting can have a significant effect on the internal corrosion of steel pipelines. This paper presents a combined experimental and molecular modeling study of several influential factors on the surface properties and corrosion behavior of mild steel in CO2 environments. The influence of different model oils (LVT-200 and Aromatic-200) and select surface-active compounds (myristic acid, cyclohexane butyric acid, and oleic acid) on the corrosion behavior of carbon steel during intermittent oil-water wetting was determined by measuring the corrosion rate after intermittent wetting cycles. The interfacial tension measurements were performed to study the incorporation of the oil phase along with surface-active molecules in the protective layer formed on the specimen surface. Results showed that the interfacial tension for an aromatic oil-water interface is lower than that for an aliphatic oil-water interface. To understand this result, molecular dynamics simulations of oil-water interfaces were performed in the presence of surface-active molecules and different oils to analyze the structure of the layer formed at the interface. The simulations supported the hypothesis that aromatic molecules are less structured at the interface, which results in the incorporation of more water molecules into the protective layer formed at the steel surface, causing a higher corrosion rate. On the other hand, the simulations revealed that myristic acid in an aliphatic oil forms a well-aligned structure at the interface, devoid of any water molecules. This is in agreement with the hypothesis that the linear molecular structure of myristic acid favors the alignment of molecules at an aliphatic oil-water interface, resulting in a lower interfacial tension and more effective corrosion mitigation as compared to the other two nonlinear compounds tested. It is concluded that an important factor controlling the corrosion behavior is the molecular structure of the oil-water interface, which is adopted by the steel surface layer through the Langmuir-Blodgett process.

12.
Inorg Chem ; 2024 Jun 21.
Artigo em Inglês | MEDLINE | ID: mdl-38904454

RESUMO

Two novel quaternary oxyarsenides, Eu8Zn2As6O and Eu14Zn5As12O, were synthesized through metal flux reactions, and their crystal structures were established by single-crystal X-ray diffraction methods. Eu8Zn2As6O crystallizes in the orthorhombic space group Pbca, featuring polyanionic ribbons composed of corner-shared triangular [ZnAs3] units, running along the [100] direction. The structure of Eu14Zn5As12O crystallizes in the monoclinic space group P2/m and its anionic substructure can be described as an infinite "ribbonlike" chain comprised of [ZnAs3] trigonal-planar units, although the structural complexity here is greater and also amplified by disorder on multiple crystallographic positions. In both structures, the O2- anion occupies an octahedral void with six neighboring Eu2+ cations. Formal electron counting, electronic structure calculations, and transport properties reveal the charge-balanced semiconducting nature of these heteroanionic Zintl phases. High-temperature thermoelectric transport properties measurements on Eu14Zn5As12O reveal relatively high resistivity (ρ500K = 8 Ω·cm) and Seebeck coefficient values (S500K = 220 µV K-1), along with a low concentration and mobility of holes as the dominant charge-carriers (n500K = 8.0 × 1017 cm-3, µ500K = 6.4 cm2/V s). Magnetic studies indicate the presence of divalent Eu2+ species in Eu14Zn5As12O and complex magnetic ordering, with two transitions observed at T1 = 21.6 K and T2 = 9 K.

13.
BJOG ; 131(9): 1167-1180, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38425020

RESUMO

BACKGROUND: Induction of labour (IOL) is common practice and different methods carry different effectiveness and safety profiles. OBJECTIVES: To compare the effectiveness, and maternal and perinatal safety outcomes of IOL with vaginal misoprostol versus vaginal dinoprostone using individual participant data from randomised clinical trials. SEARCH STRATEGY: The following databases were searched from inception to March 2023: CINAHL Plus, ClinicalTrials.gov, Cochrane Pregnancy and Childbirth Group Trial Register, Ovid Embase, Ovid Emcare, Ovid MEDLINE, Scopus and the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP). SELECTION CRITERIA: Randomised controlled trials (RCTs), with viable singleton gestation, no language restrictions, and all published and unpublished data. DATA COLLECTION AND ANALYSIS: An individual participant data meta-analysis was carried out. MAIN RESULTS: Ten of 52 eligible trials provided individual participant data, of which two were excluded after checking data integrity. The remaining eight trials compared low-dose vaginal misoprostol versus dinoprostone, including 4180 women undergoing IOL, which represents 32.8% of all participants in the published RCTs. Of these, 2077 were assigned to low-dose vaginal misoprostol and 2103 were assigned to vaginal dinoprostone. Compared with vaginal dinoprostone, low-dose vaginal misoprostol had a comparable rate of vaginal birth. Composite adverse perinatal outcomes did not differ between the groups. Compared with vaginal dinoprostone, composite adverse maternal outcomes were significantly lower with low-dose vaginal misoprostol (aOR 0.80, 95% CI 0.65-0.98, P = 0.03, I2 = 0%). CONCLUSIONS: Low-dose vaginal misoprostol and vaginal dinoprostone for IOL are comparable in terms of effectiveness and perinatal safety. However, low-dose vaginal misoprostol is likely to lead to a lower rate of composite adverse maternal outcomes than vaginal dinoprostone.


Assuntos
Maturidade Cervical , Dinoprostona , Trabalho de Parto Induzido , Misoprostol , Ocitócicos , Ensaios Clínicos Controlados Aleatórios como Assunto , Humanos , Feminino , Trabalho de Parto Induzido/métodos , Misoprostol/administração & dosagem , Misoprostol/efeitos adversos , Gravidez , Dinoprostona/administração & dosagem , Ocitócicos/administração & dosagem , Administração Intravaginal , Maturidade Cervical/efeitos dos fármacos
14.
Bioessays ; 44(4): e2100269, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35147231

RESUMO

Translation of the genetic code occurs in a cycle where ribosomes engage mRNAs, synthesize protein, and then disengage in order to repeat the process again. The final part of this process-ribosome recycling, where ribosomes dissociate from mRNAs-involves a complex molecular choreography of specific protein factors to remove the large and small subunits of the ribosome in a coordinated fashion. Errors in this process can lead to the accumulation of ribosomes at stop codons or translation of downstream open reading frames (ORFs). Ribosome recycling is also critical when a ribosome stalls during the elongation phase of translation and must be rescued to allow continued translation of the mRNA. Here we discuss the molecular interactions that drive ribosome recycling, and their regulation in the cell. We also examine the consequences of inefficient recycling with regards to disease, and its functional roles in synthesis of novel peptides, regulation of gene expression, and control of mRNA-associated proteins. Alterations in ribosome recycling efficiency have the potential to impact many cellular functions but additional work is needed to understand how this regulatory power is utilized.


Assuntos
Biossíntese de Proteínas , Ribossomos , Códon de Terminação/metabolismo , RNA Mensageiro/genética , RNA Mensageiro/metabolismo , Ribossomos/genética , Ribossomos/metabolismo
15.
J Arthroplasty ; 2024 May 21.
Artigo em Inglês | MEDLINE | ID: mdl-38782243

RESUMO

BACKGROUND: Hip resurfacing arthroplasty (HRA) is a bone-conserving alternative to total hip arthroplasty. We present the 2-year clinical and radiographic follow-up of a novel ceramic-on-ceramic HRA in an international multicenter cohort. METHODS: Patients undergoing HRA between September 2018 and January 2021 were prospectively included. Patient-reported outcome measures (PROMs) in the form of the Forgotten Joint Score, Hip Disability and Osteoarthritis Outcome Score Jr., Western Ontario and McMaster Universities Arthritis Index, Oxford Hip Score, and University of California, Los Angeles, Activity Score were collected preoperatively, and at 1 and 2 years postoperation. Serial radiographs were assessed for migration, component alignment, evidence of osteolysis or loosening, and heterotopic ossification formation. RESULTS: The study identified 200 patients who reached a minimum 2-year follow-up (mean 3.5 years). Of these, 185 completed PROMs follow-up at 2 years. There was a significant improvement in Hip Disability and Osteoarthritis Outcome Score (P < .001) and Oxford Hip Score (P < .001) between the preoperative, 1-year, and 2-year outcomes. Patients had improved activity scores on the University of California, Los Angeles, Active Score (P < .001), with 45% reporting a return to high-impact activity at 2 years. At 1 and 2 years, the Forgotten Joint Score was not significantly different (P = .38). There was no migration, osteolysis, or loosening of any of the implants. No fractures were reported over the 2-year follow-up, with only 1 patient reporting a sciatic nerve palsy. There were 2 revisions, 1 for unexplained pain at 3 months due to acetabular component malposition and 1 at 33.5 months for acetabular implant failure. CONCLUSIONS: The ceramic-on-ceramic resurfacing at 2 years postoperation demonstrates promising results with satisfactory outcomes in all recorded PROMs. Further long-term data are needed to support the widespread adoption of this prosthesis as an alternative to other HRA bearings.

16.
Molecules ; 29(11)2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38893373

RESUMO

Developing clinically meaningful nanomedicines for cancer therapy requires the drugs to be effective, safe, simple, cheap, and easy to store. In the present work, we report that a simple cationic Fe(III)-rich salt of [FeIIICl(TMPPH2)][FeIIICl4]2 (Fe-TMPP) exhibits a superior anticancer performance on a broad spectrum of cancer cell lines, including breast, colorectal cancer, liver, pancreatic, prostate, and gastric cancers, with half maximal inhibitory concentration (IC50) values in the range of 0.098-3.97 µM (0.066-2.68 µg mL-1), comparable to the best-reported medicines. Fe-TMPP can form stand-alone nanoparticles in water without the need for extra surface modification or organic-solvent-assisted antisolvent precipitation. Critically, Fe-TMPP is TME-responsive (TME = tumor microenvironment), and can only elicit its function in the TME with overexpressed H2O2, converting H2O2 to the cytotoxic •OH to oxidize the phospholipid of the cancer cell membrane, causing ferroptosis, a programmed cell death process of cancer cells.


Assuntos
Antineoplásicos , Ferroptose , Nanomedicina , Humanos , Ferroptose/efeitos dos fármacos , Linhagem Celular Tumoral , Nanomedicina/métodos , Antineoplásicos/farmacologia , Antineoplásicos/química , Nanopartículas/química , Compostos Férricos/química , Microambiente Tumoral/efeitos dos fármacos , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Neoplasias/tratamento farmacológico , Neoplasias/patologia
17.
Bioinformatics ; 38(18): 4395-4402, 2022 09 15.
Artigo em Inglês | MEDLINE | ID: mdl-35881697

RESUMO

MOTIVATION: DNA fibre assay has a potential application in genomic medicine, cancer and stem cell research at the single-molecule level. A major challenge for the clinical and research implementation of DNA fibre assays is the slow speed in which manual analysis takes place as it limits the clinical actionability. While automatic detection of DNA fibres speeds up this process considerably, current publicly available software have limited features in terms of their user interface for manual correction of results, which in turn limit their accuracy and ability to account for atypical structures that may be important in diagnosis or investigative studies. We recognize that core improvements can be made to the GUI to allow for direct interaction with automatic results to preserve accuracy as well as enhance the versatility of automatic DNA fibre detection for use in variety of situations. RESULTS: To address the unmet needs of diverse DNA fibre analysis investigations, we propose DNA Stranding, an open-source software that is able to perform accurate fibre length quantification (13.22% mean relative error) and fibre pattern recognition (R > 0.93) with up to six fibre patterns supported. With the graphical interface, we developed, user can conduct semi-automatic analyses which benefits from the advantages of both automatic and manual processes to improve workflow efficiency without compromising accuracy. AVAILABILITY AND IMPLEMENTATION: The software package is available at https://github.com/lgole/DNAStranding. SUPPLEMENTARY INFORMATION: Supplementary data are available at Bioinformatics online.


Assuntos
DNA , Software , Fluxo de Trabalho , Replicação do DNA
18.
Haematologica ; 2023 Dec 07.
Artigo em Inglês | MEDLINE | ID: mdl-38058170

RESUMO

Patients with severe aplastic anemia (SAA) are at high risk for morbidity and mortality due to severe infections. We aimed to characterize the role of granulocyte transfusion (GT) in SAA. Primary outcomes were survival from first GT, including overall survival (OS) at last follow up, survival to discharge, and receipt of HSCT. Secondary outcomes included evaluation of clinical response at 7 and 30 days after GT initiation based on a clinical scoring system incorporating microbiological and radiographic response. Twenty-eight SAA patients underwent 30 GT courses with a per-dose median of 1.28 x 109 granulocyte cells/kilogram (range 0.45-4.52 x 109). OS from initial GT to median last follow up (551 days) was 50%, with 39% (11/28) alive at last follow up. Sixty-four percent (18/28) of all patients survived to hospital discharge. Patients with complete, partial, or stable response at 30 days had significantly improved OS compared to non-responders (p=0.0004). Eighty-six percent (18/21) of patients awaiting HSCT during GT underwent transplant and 62% (13/21) survived to post-HSCT discharge. Sex, type of infection, or percentage of days with absolute neutrophil count > 0.2x109/L during GT course were not predictive of survival (p=0.52, p=0.7, p=0.28). Nine of 28 (32%) patients developed new or increased human leukocyte antigen (HLA) alloimmunization during their GT course. GTs in SAA may impact survival in those with improvement or stabilization of their underlying infection. Alloimmunization can occur and OS in this population remains poor, but GTs may be a useful tool to bridge patients to curative treatment with HSCT.

19.
Inorg Chem ; 62(16): 6439-6446, 2023 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-37053452

RESUMO

A heterobimetallic coordination polymer [Au4(dppmt)4(AgCl)2]n (1) incorporating an in situ generated P-S ligand (dppmtH) was synthesized from the solvothermal reaction of Au(tht)Cl, AgCl, and dpppyatc in CH3CN/CH2Cl2 (dppmtH = (diphenylphosphino)methanethiol, tht = tetrahydrothiophene, dpppyatc = N,N-bis((diphenylphosphaneyl)methyl)-N-(pyridin-2-yl)-amino-thiocarbamide). The structure of 1 contains a one-dimensional helical Au-Au chain in which the unique [Au4Ag2S2] cluster units are connected by [Au2(dppmt)2] dimers. Upon excitation at 343 nm, 1 exhibited cyan (495 nm) phosphorescent emission at quantum yield (QY) = 22.3% and τ = 0.78 µs (λex = 375 nm). Coordination polymer 1 exhibited a rapid, selective, reversible, and visible vapor-chromic response on exposure to methanol (MeOH) vapor with its emission shifting to a more intense green (530 nm, λex = 388 nm) with QY = 46.8% and τ = 1.24 µs (λex = 375 nm). A polymethylmethacrylate film containing 1 served as a reversible chemical sensor for the sensitive detection of MeOH in air.

20.
Chem Rev ; 121(8): 4962-4998, 2021 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-33788546

RESUMO

Since the advent of the first computers, chemists have been at the forefront of using computers to understand and solve complex chemical problems. As the hardware and software have evolved, so have the theoretical and computational chemistry methods and algorithms. Parallel computers clearly changed the common computing paradigm in the late 1970s and 80s, and the field has again seen a paradigm shift with the advent of graphical processing units. This review explores the challenges and some of the solutions in transforming software from the terascale to the petascale and now to the upcoming exascale computers. While discussing the field in general, NWChem and its redesign, NWChemEx, will be highlighted as one of the early codesign projects to take advantage of massively parallel computers and emerging software standards to enable large scientific challenges to be tackled.

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