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1.
Mol Cell ; 83(23): 4290-4303.e9, 2023 Dec 07.
Artículo en Inglés | MEDLINE | ID: mdl-37951216

RESUMEN

Reactive aldehydes are abundant endogenous metabolites that challenge homeostasis by crosslinking cellular macromolecules. Aldehyde-induced DNA damage requires repair to prevent cancer and premature aging, but it is unknown whether cells also possess mechanisms that resolve aldehyde-induced RNA lesions. Here, we establish photoactivatable ribonucleoside-enhanced crosslinking (PAR-CL) as a model system to study RNA crosslinking damage in the absence of confounding DNA damage in human cells. We find that such RNA damage causes translation stress by stalling elongating ribosomes, which leads to collisions with trailing ribosomes and activation of multiple stress response pathways. Moreover, we discovered a translation-coupled quality control mechanism that resolves covalent RNA-protein crosslinks. Collisions between translating ribosomes and crosslinked mRNA-binding proteins trigger their modification with atypical K6- and K48-linked ubiquitin chains. Ubiquitylation requires the E3 ligase RNF14 and leads to proteasomal degradation of the protein adduct. Our findings identify RNA lesion-induced translational stress as a central component of crosslinking damage.


Asunto(s)
ARN , Ubiquitina , Humanos , ARN/metabolismo , Ubiquitinación , Ubiquitina/metabolismo , Ribosomas/metabolismo , Ubiquitina-Proteína Ligasas/genética , Ubiquitina-Proteína Ligasas/metabolismo , Aldehídos , Biosíntesis de Proteínas
2.
EMBO J ; 43(4): 484-506, 2024 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-38177497

RESUMEN

Stalled ribosomes are rescued by pathways that recycle the ribosome and target the nascent polypeptide for degradation. In E. coli, these pathways are triggered by ribosome collisions through the recruitment of SmrB, a nuclease that cleaves the mRNA. In B. subtilis, the related protein MutS2 was recently implicated in ribosome rescue. Here we show that MutS2 is recruited to collisions by its SMR and KOW domains, and we reveal the interaction of these domains with collided ribosomes by cryo-EM. Using a combination of in vivo and in vitro approaches, we show that MutS2 uses its ABC ATPase activity to split ribosomes, targeting the nascent peptide for degradation through the ribosome quality control pathway. However, unlike SmrB, which cleaves mRNA in E. coli, we see no evidence that MutS2 mediates mRNA cleavage or promotes ribosome rescue by tmRNA. These findings clarify the biochemical and cellular roles of MutS2 in ribosome rescue in B. subtilis and raise questions about how these pathways function differently in diverse bacteria.


Asunto(s)
Bacillus subtilis , Biosíntesis de Proteínas , ARN Mensajero/metabolismo , Bacillus subtilis/genética , Bacillus subtilis/metabolismo , Escherichia coli/genética , Escherichia coli/metabolismo , Ribosomas/metabolismo , Péptidos/metabolismo
3.
Nature ; 603(7901): 503-508, 2022 03.
Artículo en Inglés | MEDLINE | ID: mdl-35264790

RESUMEN

Ribosome rescue pathways recycle stalled ribosomes and target problematic mRNAs and aborted proteins for degradation1,2. In bacteria, it remains unclear how rescue pathways distinguish ribosomes stalled in the middle of a transcript from actively translating ribosomes3-6. Here, using a genetic screen in Escherichia coli, we discovered a new rescue factor that has endonuclease activity. SmrB cleaves mRNAs upstream of stalled ribosomes, allowing the ribosome rescue factor tmRNA (which acts on truncated mRNAs3) to rescue upstream ribosomes. SmrB is recruited to ribosomes and is activated by collisions. Cryo-electron microscopy structures of collided disomes from E. coli and Bacillus subtilis show distinct and conserved arrangements of individual ribosomes and the composite SmrB-binding site. These findings reveal the underlying mechanisms by which ribosome collisions trigger ribosome rescue in bacteria.


Asunto(s)
Escherichia coli , Ribosomas , Bacterias/genética , Microscopía por Crioelectrón , Escherichia coli/genética , Escherichia coli/metabolismo , Biosíntesis de Proteínas , ARN Bacteriano/metabolismo , ARN Mensajero/metabolismo , Ribosomas/metabolismo
4.
Mol Cell ; 70(5): 759-760, 2018 06 07.
Artículo en Inglés | MEDLINE | ID: mdl-29883601

RESUMEN

Culviner and Laub (2018) use RNA-seq and ribosome profiling to determine how MazF inhibits translation in E. coli. Challenging an earlier model, they argue that MazF cleaves mRNA and blocks ribosome biogenesis but does not generate specialized ribosomes that preferentially translate leaderless transcripts.


Asunto(s)
Escherichia coli/genética , ARN Mensajero , Proteínas de Unión al ADN , Endorribonucleasas , Proteínas de Escherichia coli , ARN Ribosómico , Ribosomas
5.
Nucleic Acids Res ; 2024 May 30.
Artículo en Inglés | MEDLINE | ID: mdl-38811035

RESUMEN

Ribosomes trapped on mRNAs during protein synthesis need to be rescued for the cell to survive. The most ubiquitous bacterial ribosome rescue pathway is trans-translation mediated by tmRNA and SmpB. Genetic inactivation of trans-translation can be lethal, unless ribosomes are rescued by ArfA or ArfB alternative rescue factors or the ribosome-associated quality control (RQC) system, which in Bacillus subtilis involves MutS2, RqcH, RqcP and Pth. Using transposon sequencing in a trans-translation-incompetent B. subtilis strain we identify a poorly characterized S4-domain-containing protein YlmH as a novel potential RQC factor. Cryo-EM structures reveal that YlmH binds peptidyl-tRNA-50S complexes in a position analogous to that of S4-domain-containing protein RqcP, and that, similarly to RqcP, YlmH can co-habit with RqcH. Consistently, we show that YlmH can assume the role of RqcP in RQC by facilitating the addition of poly-alanine tails to truncated nascent polypeptides. While in B. subtilis the function of YlmH is redundant with RqcP, our taxonomic analysis reveals that in multiple bacterial phyla RqcP is absent, while YlmH and RqcH are present, suggesting that in these species YlmH plays a central role in the RQC.

6.
Mol Cell ; 66(2): 194-205.e5, 2017 Apr 20.
Artículo en Inglés | MEDLINE | ID: mdl-28392174

RESUMEN

The eukaryotic translation factor eIF5A, originally identified as an initiation factor, was later shown to promote translation elongation of iterated proline sequences. Using a combination of ribosome profiling and in vitro biochemistry, we report a much broader role for eIF5A in elongation and uncover a critical function for eIF5A in termination. Ribosome profiling of an eIF5A-depleted strain reveals a global elongation defect, with abundant ribosomes stalling at many sequences, not limited to proline stretches. Our data also show ribosome accumulation at stop codons and in the 3' UTR, suggesting a global defect in termination in the absence of eIF5A. Using an in vitro reconstituted translation system, we find that eIF5A strongly promotes the translation of the stalling sequences identified by profiling and increases the rate of peptidyl-tRNA hydrolysis more than 17-fold. We conclude that eIF5A functions broadly in elongation and termination, rationalizing its high cellular abundance and essential nature.


Asunto(s)
Extensión de la Cadena Peptídica de Translación , Terminación de la Cadena Péptídica Traduccional , Factores de Iniciación de Péptidos/metabolismo , Proteínas de Unión al ARN/metabolismo , Ribosomas/metabolismo , Proteínas de Saccharomyces cerevisiae/metabolismo , Saccharomyces cerevisiae/metabolismo , Regiones no Traducidas 3' , Secuencias de Aminoácidos , Codón de Terminación , Perfilación de la Expresión Génica/métodos , Hidrólisis , Cinética , Factores de Iniciación de Péptidos/genética , Factores de Terminación de Péptidos/genética , Factores de Terminación de Péptidos/metabolismo , Péptidos/metabolismo , Peptidil Transferasas/genética , Peptidil Transferasas/metabolismo , ARN de Hongos/genética , ARN de Hongos/metabolismo , Aminoacil-ARN de Transferencia/genética , Aminoacil-ARN de Transferencia/metabolismo , Proteínas de Unión al ARN/genética , Ribosomas/genética , Saccharomyces cerevisiae/genética , Proteínas de Saccharomyces cerevisiae/genética , Factor 5A Eucariótico de Iniciación de Traducción
7.
Clin Infect Dis ; 78(5): 1204-1213, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38227643

RESUMEN

BACKGROUND: Infection prevention (IP) measures are designed to mitigate the transmission of pathogens in healthcare. Using large-scale viral genomic and social network analyses, we determined if IP measures used during the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) pandemic were adequate in protecting healthcare workers (HCWs) and patients from acquiring SARS-CoV-2. METHODS: We performed retrospective cross-sectional analyses of viral genomics from all available SARS-CoV-2 viral samples collected at UC San Diego Health and social network analysis using the electronic medical record to derive temporospatial overlap of infections among related viromes and supplemented with contact tracing data. The outcome measure was any instance of healthcare transmission, defined as cases with closely related viral genomes and epidemiological connection within the healthcare setting during the infection window. Between November 2020 through January 2022, 12 933 viral genomes were obtained from 35 666 patients and HCWs. RESULTS: Among 5112 SARS-CoV-2 viral samples sequenced from the second and third waves of SARS-CoV-2 (pre-Omicron), 291 pairs were derived from persons with a plausible healthcare overlap. Of these, 34 pairs (12%) were phylogenetically linked: 19 attributable to household and 14 to healthcare transmission. During the Omicron wave, 2106 contact pairs among 7821 sequences resulted in 120 (6%) related pairs among 32 clusters, of which 10 were consistent with healthcare transmission. Transmission was more likely to occur in shared spaces in the older hospital compared with the newer hospital (2.54 vs 0.63 transmission events per 1000 admissions, P < .001). CONCLUSIONS: IP strategies were effective at identifying and preventing healthcare SARS-CoV-2 transmission.


Asunto(s)
COVID-19 , Genoma Viral , Personal de Salud , SARS-CoV-2 , Humanos , COVID-19/transmisión , COVID-19/epidemiología , COVID-19/virología , SARS-CoV-2/genética , Estudios Retrospectivos , Estudios Transversales , Masculino , Femenino , Adulto , Persona de Mediana Edad , Anciano , Análisis de Redes Sociales , Trazado de Contacto , Genómica , Adulto Joven , Adolescente , Niño , Anciano de 80 o más Años , Infección Hospitalaria/transmisión , Infección Hospitalaria/virología , Infección Hospitalaria/epidemiología , Preescolar
8.
EMBO J ; 39(3): e103365, 2020 02 03.
Artículo en Inglés | MEDLINE | ID: mdl-31858614

RESUMEN

Inhibitory codon pairs and poly(A) tracts within the translated mRNA cause ribosome stalling and reduce protein output. The molecular mechanisms that drive these stalling events, however, are still unknown. Here, we use a combination of in vitro biochemistry, ribosome profiling, and cryo-EM to define molecular mechanisms that lead to these ribosome stalls. First, we use an in vitro reconstituted yeast translation system to demonstrate that inhibitory codon pairs slow elongation rates which are partially rescued by increased tRNA concentration or by an artificial tRNA not dependent on wobble base-pairing. Ribosome profiling data extend these observations by revealing that paused ribosomes with empty A sites are enriched on these sequences. Cryo-EM structures of stalled ribosomes provide a structural explanation for the observed effects by showing decoding-incompatible conformations of mRNA in the A sites of all studied stall- and collision-inducing sequences. Interestingly, in the case of poly(A) tracts, the inhibitory conformation of the mRNA in the A site involves a nucleotide stacking array. Together, these data demonstrate a novel mRNA-induced mechanisms of translational stalling in eukaryotic ribosomes.


Asunto(s)
Biosíntesis de Proteínas , ARN Mensajero/genética , Ribosomas/metabolismo , Saccharomyces cerevisiae/metabolismo , Codón , Microscopía por Crioelectrón , Modelos Moleculares , Conformación de Ácido Nucleico , Poli A/metabolismo , ARN Mensajero/química , ARN Mensajero/metabolismo , ARN de Transferencia/metabolismo , Saccharomyces cerevisiae/genética
9.
Pediatr Nephrol ; 39(3): 745-748, 2024 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-37874356

RESUMEN

Post-infectious glomerulonephritis (PIGN) is an immune complex mediated glomerular injury occurring because of an infection, most commonly with group A beta-hemolytic streptococcus in children. C3 glomerulopathy (C3G) is a distinct clinicopathological entity occurring secondary to dysregulation of alternate complement pathway encompassing both C3 glomerulonephritis (C3GN) and dense deposit disease (DDD). While most patients with PIGN attain complete remission with normalized complement levels by 6-8 weeks after presentation, patients with C3G continue to have hypocomplementemia with high rates of progressive kidney disease. Here, we report a patient diagnosed with dense deposit disease after his initial presentation with PIGN three years prior. While current literature continues to explore the overlapping and distinguishing features of PIGN and C3G, including how underlying defects in the alternate complement pathway may commonly contribute to both diseases, this case further exemplifies the importance of recognizing the clinico-pathogenic features of PIGN and C3G in pediatric patients with glomerulonephritis.


Asunto(s)
Glomerulonefritis Membranoproliferativa , Glomerulonefritis , Enfermedades Renales , Humanos , Niño , Complemento C3 , Glomerulonefritis/diagnóstico , Glomerulonefritis/etiología , Glomérulos Renales/patología , Enfermedades Renales/patología
10.
Mem Cognit ; 2024 Feb 20.
Artículo en Inglés | MEDLINE | ID: mdl-38378883

RESUMEN

Research has demonstrated that individuals can direct their attention to valuable information in both working memory and long-term memory tasks with observable effects on performance. However, it is currently unclear whether prioritising an item for a working memory task automatically translates into a boost at long-term memory. This was examined in two experiments using relatively short (250 ms per item; Experiment 1) and longer (500 ms per item; Experiment 2) encoding times. Participants first completed a visual working memory task, in which they were presented with series of photographs of everyday objects. Following a brief delay (1,000 ms), they completed a four-alternative forced-choice test. Prior to encoding, participants were informed of the point values associated with each item. In some trials, the first item in the sequence was worth more points than the rest. In other trials, all items were equally valuable. After a filled delay, participants completed a surprise long-term memory task. At working memory, a value effect was reliably observed on recognition accuracy, along with some evidence of faster response times for high-value items. However, there was little consistent evidence of this effect automatically persisting into long-term memory. Thus, the benefits of attentional prioritization in working memory do not always translate into longer-term performance. More broadly, this provides further evidence that manipulations that enhance working memory performance do not necessarily enhance long-term memory.

11.
Pediatr Radiol ; 54(1): 117-126, 2024 01.
Artículo en Inglés | MEDLINE | ID: mdl-38072887

RESUMEN

BACKGROUND: In boys with Duchenne muscular dystrophy (DMD), initiation of bisphosphonate is recommended upon identification of moderate or severe vertebral fractures, even if asymptomatic. Clear radiological reporting is important for consistency of clinical interpretation and management. OBJECTIVES: To audit radiology reports of spine imaging for vertebral fracture assessment in DMD, and assess potential impact on diagnosis and management. MATERIALS AND METHODS: Lateral thoracolumbar spine imaging (71 lateral spine radiographs and 13 lateral dual energy absorptiometry spine image) in 84 boys with DMD performed across two centres. Anonymised radiology reports by paediatric radiologists were circulated to two neuromuscular clinicians and two endocrinologists. Clinicians determined if there was vertebral fracture, no vertebral fracture, or unclear interpretation. Endocrinologists also determined if bisphosphonate was indicated. A single observer (a clinician with expertise in vertebral fracture assessment) performed vertebral fracture assessment in 37 images and re-reported using a structured format. Structured reports were re-circulated to the four clinicians to re-evaluate the degree of concordance in clinical diagnosis of vertebral fracture and treatment decisions with bisphosphonate. RESULTS: The term "fracture" was used in 25/84 (30%) radiology reports and only in 8/43 (19%) with description of vertebral body abnormalities. Fracture grading was included in 7/43 (16%) radiology reports. Diagnostic concordance by the clinicians was noted in 36/84 (43%). Unclear interpretation was noted in 22% to 51% based on radiology reports. No unclear interpretation was noted with structured reports. Complete diagnostic (37/37, 100%) and treatment (37/37, 100%) concordance was noted with the structured reports, whereas complete diagnostic and treatment concordance was noted in only 16/37 (43%) and 17/37 (46%) of the radiology reports, respectively. CONCLUSION: Only a third of radiology reports of spine imaging in DMD explicitly used the terminology "fracture". Grading was only noted in a small percentage. Variability in diagnostic interpretation by clinicians may lead to differing management plans. As identification of vertebral fracture is a trigger for treatment, developing reporting guidelines for paediatric vertebral fracture assessment will improve care. A structured template should be introduced for radiological reporting of paediatric vertebral fracture assessment.


Asunto(s)
Distrofia Muscular de Duchenne , Fracturas Osteoporóticas , Fracturas de la Columna Vertebral , Masculino , Humanos , Niño , Fracturas de la Columna Vertebral/diagnóstico por imagen , Fracturas de la Columna Vertebral/terapia , Distrofia Muscular de Duchenne/complicaciones , Distrofia Muscular de Duchenne/diagnóstico por imagen , Distrofia Muscular de Duchenne/tratamiento farmacológico , Columna Vertebral , Fracturas Osteoporóticas/diagnóstico por imagen , Fracturas Osteoporóticas/terapia , Difosfonatos
12.
Chaos ; 34(1)2024 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-38271631

RESUMEN

Networks of coupled nonlinear oscillators can display a wide range of emergent behaviors under the variation of the strength of the coupling. Network equations for pairs of coupled oscillators where the dynamics of each node is described by the evolution of its phase and slowest decaying isostable coordinate have previously been shown to capture bifurcations and dynamics of the network, which cannot be explained through standard phase reduction. An alternative framework using isostable coordinates to obtain higher-order phase reductions has also demonstrated a similar descriptive ability for two oscillators. In this work, we consider the phase-isostable network equations for an arbitrary but finite number of identical coupled oscillators, obtaining conditions required for the stability of phase-locked states including synchrony. For the mean-field complex Ginzburg-Landau equation where the solutions of the full system are known, we compare the accuracy of the phase-isostable network equations and higher-order phase reductions in capturing bifurcations of phase-locked states. We find the former to be the more accurate and, therefore, employ this to investigate the dynamics of globally linearly coupled networks of Morris-Lecar neuron models (both two and many nodes). We observe qualitative correspondence between results from numerical simulations of the full system and the phase-isostable description demonstrating that in both small and large networks, the phase-isostable framework is able to capture dynamics that the first-order phase description cannot.

13.
Cogn Emot ; : 1-15, 2024 Mar 30.
Artículo en Inglés | MEDLINE | ID: mdl-38554262

RESUMEN

Across four studies, we explored how feeling nostalgic about an attitude object impacts the metacognitive characteristics of the attitude toward that object and how those metacognitions predict the evaluation's underlying strength. In each study, participants reflected on and evaluated a song or television show that either did or did not elicit nostalgia. Across these studies, we found support for the hypotheses that nostalgic attitude objects are viewed more positively, appraised with greater attitudinal importance, and exhibited less objective ambivalence. In Study 4, we observed that nostalgic attitudes are associated with greater behavioural intentions and that this relationship was mediated both by attitudinal importance and objective ambivalence. These studies contribute to our understanding of how nostalgia affects attitude formation processes.

14.
J Bacteriol ; 205(2): e0037022, 2023 02 22.
Artículo en Inglés | MEDLINE | ID: mdl-36651772

RESUMEN

The universally conserved protein elongation factor P (EF-P) facilitates translation at amino acids that form peptide bonds with low efficiency, particularly polyproline tracts. Despite its wide conservation, it is not essential in most bacteria and its physiological role remains unclear. Here, we show that EF-P affects the process of sporulation initiation in the bacterium Bacillus subtilis. We observe that the lack of EF-P delays expression of sporulation-specific genes. Using ribosome profiling, we observe that expression of spo0A, encoding a transcription factor that functions as the master regulator of sporulation, is lower in a Δefp strain than the wild type. Ectopic expression of Spo0A rescues the sporulation initiation phenotype, indicating that reduced spo0A expression explains the sporulation defect in Δefp cells. Since Spo0A is the earliest sporulation transcription factor, these data suggest that sporulation initiation can be delayed when protein synthesis is impaired. IMPORTANCE Elongation factor P (EF-P) is a universally conserved translation factor that prevents ribosome stalling at amino acids that form peptide bonds with low efficiency, particularly polyproline tracts. Phenotypes associated with EF-P deletion are pleiotropic, and the mechanistic basis underlying many of these phenotypes is unclear. Here, we show that the absence of EF-P affects the ability of B. subtilis to initiate sporulation by preventing normal expression of Spo0A, the key transcriptional regulator of this process. These data illustrate a mechanism that accounts for the sporulation delay and further suggest that cells are capable of sensing translation stress before committing to sporulation.


Asunto(s)
Proteínas Bacterianas , Factores de Transcripción , Proteínas Bacterianas/genética , Factores de Transcripción/metabolismo , Factores de Elongación de Péptidos/genética , Aminoácidos/metabolismo , Esporas Bacterianas/genética , Bacillus subtilis/genética , Regulación Bacteriana de la Expresión Génica
15.
Plant Mol Biol ; 112(4-5): 279-291, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-37326800

RESUMEN

A long-held goal of synthetic biology has been the transfer of a bacterial nitrogen-fixation pathway into plants to reduce the use of chemical fertiliser on crops such as rice, wheat and maize. There are three classes of bacterial nitrogenase, named after their metal requirements, containing either a MoFe-, VFe- or FeFe-cofactor, that converts N2 gas to ammonia. Relative to the Mo-nitrogenase the Fe-nitrogenase is not as efficient for catalysis but has less complex genetic and metallocluster requirements, features that may be preferable for engineering into crops. Here we report the successful targeting of bacterial Fe-nitrogenase proteins, AnfD, AnfK, AnfG and AnfH, to plant mitochondria. When expressed as a single protein AnfD was mostly insoluble in plant mitochondria, but coexpression of AnfD with AnfK improved its solubility. Using affinity-based purification of mitochondrially expressed AnfK or AnfG we were able to demonstrate a strong interaction of AnfD with AnfK and a weaker interaction of AnfG with AnfDK. This work establishes that the structural components of the Fe-nitrogenase can be engineered into plant mitochondria and form a complex, which will be a requirement for function. This report outlines the first use of Fe-nitrogenase proteins within a plant as a preliminary step towards engineering an alternative nitrogenase into crops.


Asunto(s)
Azotobacter vinelandii , Nitrogenasa , Nitrogenasa/genética , Nitrogenasa/metabolismo , Azotobacter vinelandii/genética , Azotobacter vinelandii/metabolismo , Hierro , Fijación del Nitrógeno , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo
16.
Pediatr Crit Care Med ; 24(8): 662-669, 2023 08 01.
Artículo en Inglés | MEDLINE | ID: mdl-37102713

RESUMEN

OBJECTIVES: To investigate outcomes associated with conventional roller or centrifugal pumps during neonatal venovenous extracorporeal membrane oxygenation (ECMO). Our primary hypothesis is that in comparison with conventional roller-pump support, centrifugal pump use is associated with greater odds of survival. Our secondary hypothesis is that centrifugal pump use is associated with lesser odds of complications. DESIGN: Retrospective cohort identified using the Extracorporeal Life Support Organization (ELSO) registry 2016 to 2020 dataset. SETTING: All ECMO centers reporting to the ELSO registry. PATIENTS: All neonates (≤ 28 d) supported with venovenous ECMO and cannulated via right internal jugular vein using dual-lumen venovenous cannulas and polymethyl pentene membrane oxygenators. INTERVENTIONS: None. MEASUREMENTS AND MAIN RESULTS: A total of 612 neonates (centrifugal, n = 340; conventional roller, n = 272) were included in the analysis. Using a multivariable logistic regression model, centrifugal pump use-as opposed to roller pump use-was associated with lesser odds of survival (odds ratio [OR], 0.53; 95% CI, 0.33-0.84; p < 0.008). Thrombosis and clots in the circuit components were also associated with lesser odds of survival (OR, 0.28; 95% CI, 0.16-0.60; p < 0.001). We failed to show that hemolysis was an independent variable for survival (OR, 0.60; 95% CI, 0.31-1.19; p = 0.14). The primary diagnosis of neonatal aspiration/meconium aspiration is associated with more than seven-fold greater odds of survival (OR, 7.57; 95% CI, 4.02-15.74; p < 0.001). CONCLUSIONS: Contrary to our hypotheses, conventional roller pump use was associated with greater odds of survival. While thrombosis and clots in circuit components were independent variables for lesser odds of survival, further research is needed better to understand the use of centrifugal pumps in neonatal practice.


Asunto(s)
Oxigenación por Membrana Extracorpórea , Síndrome de Aspiración de Meconio , Femenino , Humanos , Recién Nacido , Oxigenación por Membrana Extracorpórea/efectos adversos , Estudios Retrospectivos , Oxigenadores de Membrana , Morbilidad
17.
Am J Addict ; 32(3): 309-313, 2023 05.
Artículo en Inglés | MEDLINE | ID: mdl-36504413

RESUMEN

BACKGROUND AND OBJECTIVES: The involvement of xylazine, a veterinary drug, in West Virginia (WV) human drug-related deaths was examined. METHODS: WV drug deaths from 2019 (when xylazine was first identified) to mid-2021. Characteristics including toxicology findings were compared between xylazine and nonxylazine deaths. RESULTS: Of 3292 drug deaths, 117 involved xylazine, and the proportions of deaths with it have increased (1% [2019] to 5% [mid-2021)]. Xylazine decedents had more cointoxicants, with fentanyl (98%) predominant followed by methamphetamine. Xylazine decedents had a significantly greater history of drug or alcohol misuse and hepatic disease. CONCLUSIONS AND SCIENTIFIC SIGNIFICANCE: In one of the largest analyses of xylazine-involved deaths in a predominantly rural state, identification of xylazine was increasing with multiple cointoxicants (especially fentanyl), and was present in a few deaths with only one other substance involved. Health professionals should be aware of possible enhanced toxicity from xylazine ingestion especially since naloxone does not reverse xylazine's adverse effects.


Asunto(s)
Sobredosis de Droga , Xilazina , Humanos , Xilazina/efectos adversos , West Virginia/epidemiología , Fentanilo/efectos adversos
18.
J Toxicol Environ Health A ; 86(9): 263-282, 2023 05 03.
Artículo en Inglés | MEDLINE | ID: mdl-36883736

RESUMEN

Alcohol-to-jet (ATJ) Synthetic Kerosene with Aromatics (SKA) fuels are produced by dehydration and refining of alcohol feed stocks. ATJ SKA fuel known as SB-8 was developed by Swedish Biofuels as a cooperative agreement between Sweden and AFRL/RQTF. SB-8 including standard additives was tested in a 90-day toxicity study with male and female Fischer 344 rats exposed to 0, 200, 700, or 2000 mg/m3 fuel in an aerosol/vapor mixture for 6 hr/day, 5 days/week. Aerosols represented 0.04 and 0.84% average fuel concentration in 700 or 2000 mg/m3 exposure groups. Examination of vaginal cytology and sperm parameters found no marked changes in reproductive health. Neurobehavioral effects were increased rearing activity (motor activity) and significantly decreased grooming (functional observational battery) in 2000 mg/m3 female rats. Hematological changes were limited to elevated platelet counts in 2000 mg/m3 exposed males. Minimal focal alveolar epithelial hyperplasia with increased number of alveolar macrophages was noted in some 2000 mg/m3 males and one female rat. Additional rats tested for genotoxicity by micronucleus (MN) formation did not detect bone marrow cell toxicity or alterations in number of MN; SB-8 was not clastogenic. Inhalation results were similar to effects reported for JP-8. Both JP-8 and SB fuels were moderately irritating under occlusive wrapped conditions but slightly irritating under semi-occlusion. Exposure to SB-8, alone or as 50:50 blend with petroleum-derived JP-8, is not likely to enhance adverse human health risks in the military workplace.


Asunto(s)
Queroseno , Semen , Humanos , Ratas , Masculino , Femenino , Animales , Queroseno/toxicidad , Suecia , Hidrocarburos/toxicidad , Ratas Endogámicas F344 , Aerosoles , Etanol
19.
Anaesthesia ; 78(10): 1237-1248, 2023 10.
Artículo en Inglés | MEDLINE | ID: mdl-37365700

RESUMEN

Modified-release opioids are often prescribed for the management of moderate to severe acute pain following total hip and knee arthroplasty, despite recommendations against their use due to increasing concerns regarding harm. The primary objective of this multicentre study was to examine the impact of modified-release opioid use on the incidence of opioid-related adverse events compared with immediate-release opioid use, among adult inpatients following total hip or knee arthroplasty. Data for total hip and knee arthroplasty inpatients receiving an opioid analgesic for postoperative analgesia during hospitalisation were collected from electronic medical records of three tertiary metropolitan hospitals in Australia. The primary outcome was the incidence of opioid-related adverse events during hospital admission. Patients who received modified with or without immediate-release opioids were matched to those receiving immediate-release opioids only (1:1) using nearest neighbour propensity score matching with patient and clinical characteristics as covariates. This included total opioid dose received. In the matched cohorts, patients given modified-release opioids (n = 347) experienced a higher incidence of opioid-related adverse events overall, compared with those given immediate-release opioids only (20.5%, 71/347 vs. 12.7%, 44/347; difference in proportions 7.8% [95%CI 2.3-13.3%]). Modified-release opioid use was associated with an increased risk of harm when used for acute pain during hospitalisation after total hip or knee arthroplasty.


Asunto(s)
Dolor Agudo , Artroplastia de Reemplazo de Cadera , Artroplastia de Reemplazo de Rodilla , Trastornos Relacionados con Opioides , Adulto , Humanos , Analgésicos Opioides/uso terapéutico , Estudios de Cohortes , Artroplastia de Reemplazo de Rodilla/efectos adversos , Dolor Postoperatorio/tratamiento farmacológico , Puntaje de Propensión , Dolor Agudo/tratamiento farmacológico , Artroplastia de Reemplazo de Cadera/efectos adversos , Trastornos Relacionados con Opioides/etiología , Estudios Retrospectivos
20.
Eur Spine J ; 32(4): 1123-1131, 2023 04.
Artículo en Inglés | MEDLINE | ID: mdl-36740606

RESUMEN

PURPOSE: The purpose of this study was to understand potential baseline transcriptional expression differences in paraspinal skeletal muscle from patients with different underlying lumbar pathologies by comparing multifidus gene expression profiles across individuals with either disc herniation, facet arthropathy, or degenerative spondylolisthesis. METHODS: Multifidus biopsies were obtained from patients (n = 44) undergoing lumbar surgery for either disc herniation, facet arthropathy, or degenerative spondylolisthesis. Diagnostic categories were based on magnetic resonance images, radiology reports, and intraoperative reports. Gene expression for 42 genes was analysed using qPCR. A one-way analysis of variance was performed for each gene to determine differences in expression across diagnostic groups. Corrections for multiple comparisons across genes (Benjamini-Hochberg) and for between-group post hoc comparisons (Sidak) were applied. RESULTS: Adipogenic gene (ADIPOQ) expression was higher in the disc herniation group when compared to the facet arthropathy group (p = 0.032). Adipogenic gene (PPARD) expression was higher in the degenerative spondylolisthesis group when compared to the disc herniation group (p = 0.013), although absolute gene expression levels for all groups was low. Fibrogenic gene (COL3A1) had significantly higher expression in the disc herniation group and facet arthropathy group when compared to the degenerative spondylolisthesis group (p < 0.001 and p = 0.038, respectively). When adjusted for multiple comparisons, only COL3A1 remained significant (p = 0.012). CONCLUSION: Individuals with disc herniation and facet arthropathy demonstrate higher COL3A1 gene expression compared to those with degenerative spondylolisthesis. Future research is required to further understand the biological relevance of these transcriptional differences.


Asunto(s)
Degeneración del Disco Intervertebral , Desplazamiento del Disco Intervertebral , Artropatías , Espondilolistesis , Humanos , Desplazamiento del Disco Intervertebral/genética , Desplazamiento del Disco Intervertebral/cirugía , Desplazamiento del Disco Intervertebral/complicaciones , Degeneración del Disco Intervertebral/diagnóstico por imagen , Degeneración del Disco Intervertebral/genética , Degeneración del Disco Intervertebral/cirugía , Espondilolistesis/diagnóstico por imagen , Espondilolistesis/genética , Espondilolistesis/cirugía , Músculos Paraespinales/diagnóstico por imagen , Músculos Paraespinales/patología , Vértebras Lumbares/diagnóstico por imagen , Vértebras Lumbares/cirugía , Vértebras Lumbares/patología , Imagen por Resonancia Magnética/efectos adversos , Expresión Génica
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