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1.
Nature ; 628(8008): 648-656, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38538789

RESUMO

Dynamically organized chromatin complexes often involve multiplex chromatin interactions and sometimes chromatin-associated RNA1-3. Chromatin complex compositions change during cellular differentiation and ageing, and are expected to be highly heterogeneous among terminally differentiated single cells4-7. Here we introduce the multinucleic acid interaction mapping in single cells (MUSIC) technique for concurrent profiling of multiplex chromatin interactions, gene expression and RNA-chromatin associations within individual nuclei. When applied to 14 human frontal cortex samples from older donors, MUSIC delineated diverse cortical cell types and states. We observed that nuclei exhibiting fewer short-range chromatin interactions were correlated with both an 'older' transcriptomic signature and Alzheimer's disease pathology. Furthermore, the cell type exhibiting chromatin contacts between cis expression quantitative trait loci and a promoter tends to be that in which these cis expression quantitative trait loci specifically affect the expression of their target gene. In addition, female cortical cells exhibit highly heterogeneous interactions between XIST non-coding RNA and chromosome X, along with diverse spatial organizations of the X chromosomes. MUSIC presents a potent tool for exploration of chromatin architecture and transcription at cellular resolution in complex tissues.


Assuntos
Envelhecimento , Núcleo Celular , Cromatina , Lobo Frontal , RNA , Análise de Célula Única , Idoso , Feminino , Humanos , Masculino , Envelhecimento/genética , Doença de Alzheimer/genética , Doença de Alzheimer/patologia , Núcleo Celular/genética , Senescência Celular/genética , Cromatina/genética , Cromatina/metabolismo , Cromossomos Humanos X/genética , Cromossomos Humanos X/metabolismo , Lobo Frontal/metabolismo , Perfilação da Expressão Gênica/métodos , Regiões Promotoras Genéticas , Locos de Características Quantitativas , RNA/genética , RNA/metabolismo , RNA Longo não Codificante/genética , RNA Longo não Codificante/metabolismo , Análise de Célula Única/métodos , Transcrição Gênica
2.
PLoS Pathog ; 20(2): e1012054, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38416776

RESUMO

The unicellular parasite Leishmania has a precisely defined cell architecture that is inherited by each subsequent generation, requiring a highly coordinated pattern of duplication and segregation of organelles and cytoskeletal structures. A framework of nuclear division and morphological changes is known from light microscopy, yet this has limited resolution and the intrinsic organisation of organelles within the cell body and their manner of duplication and inheritance is unknown. Using volume electron microscopy approaches, we have produced three-dimensional reconstructions of different promastigote cell cycle stages to give a spatial and quantitative overview of organelle positioning, division and inheritance. The first morphological indications seen in our dataset that a new cell cycle had begun were the assembly of a new flagellum, the duplication of the contractile vacuole and the increase in volume of the nucleus and kinetoplast. We showed that the progression of the cytokinesis furrow created a specific pattern of membrane indentations, while our analysis of sub-pellicular microtubule organisation indicated that there is likely a preferred site of new microtubule insertion. The daughter cells retained these indentations in their cell body for a period post-abscission. By comparing cultured and sand fly derived promastigotes, we found an increase in the number and overall volume of lipid droplets in the promastigotes from the sand fly, reflecting a change in their metabolism to ensure transmissibility to the mammalian host. Our insights into the cell cycle mechanics of Leishmania will support future molecular cell biology analyses of these parasites.


Assuntos
Leishmania mexicana , Leishmania , Parasitos , Psychodidae , Animais , Leishmania mexicana/genética , Ciclo Celular , Divisão Celular , Psychodidae/parasitologia , Mamíferos
3.
Biochemistry ; 63(8): 1016-1025, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38546289

RESUMO

Kinetic parameters are reported for glycerol 3-phosphate dehydrogenase (GPDH)-catalyzed hydride transfer from the whole substrate glycerol 3-phosphate (G3P) or truncated substrate ethylene glycol (EtG) to NAD, and for activation of the hydride transfer reaction of EtG by phosphite dianion. These kinetic parameters were combined with parameters for enzyme-catalyzed hydride transfer in the microscopic reverse direction to give the reaction equilibrium constants Keq. Hydride transfer from G3P is favored in comparison to EtG because the carbonyl product of the former reaction is stabilized by hyperconjugative electron donation from the -CH2R keto substituent. The kinetic data show that the phosphite dianion provides the same 7.6 ± 0.1 kcal/mol stabilization of the transition states for enzyme-catalyzed reactions in the forward [reduction of NAD by EtG] and reverse [oxidation of NADH by glycolaldehyde] directions. The experimental evidence that supports a role for phosphite dianion in stabilizing the active closed form of the GPDH (EC) relative to the ca. 6 kcal/mol more unstable open form (EO) is summarized.


Assuntos
Glicerolfosfato Desidrogenase , Glicerofosfatos , Fosfitos , Glicerolfosfato Desidrogenase/química , NAD/metabolismo , Catálise , Cinética
4.
Prostate ; 84(10): 977-990, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-38654435

RESUMO

BACKGROUND: It is important to identify molecular features that improve prostate cancer (PCa) risk stratification before radical treatment with curative intent. Molecular analysis of historical diagnostic formalin-fixed paraffin-embedded (FFPE) prostate biopsies from cohorts with post-radiotherapy (RT) long-term clinical follow-up has been limited. Utilizing parallel sequencing modalities, we performed a proof-of-principle sequencing analysis of historical diagnostic FFPE prostate biopsies. We compared patients with (i) stable PCa (sPCa) postprimary or salvage RT, (ii) progressing PCa (pPCa) post-RT, and (iii) de novo metastatic PCa (mPCa). METHODS: A cohort of 19 patients with diagnostic prostate biopsies (n = 6 sPCa, n = 5 pPCa, n = 8 mPCa) and mean 4 years 10 months follow-up (diagnosed 2009-2016) underwent nucleic acid extraction from demarcated malignancy. Samples underwent 3'RNA sequencing (3'RNAseq) (n = 19), nanoString analysis (n = 12), and Illumina 850k methylation (n = 8) sequencing. Bioinformatic analysis was performed to coherently identify differentially expressed genes and methylated genomic regions (MGRs). RESULTS: Eighteen of 19 samples provided useable 3'RNAseq data. Principal component analysis (PCA) demonstrated similar expression profiles between pPCa and mPCa cases, versus sPCa. Coherently differentially methylated probes between these groups identified ~600 differentially MGRs. The top 50 genes with increased expression in pPCa patients were associated with reduced progression-free survival post-RT (p < 0.0001) in an external cohort. CONCLUSIONS: 3'RNAseq, nanoString and 850k-methylation analyses are each achievable from historical FFPE diagnostic pretreatment prostate biopsies, unlocking the potential to utilize large cohorts of historic clinical samples. Profiling similarities between individuals with pPCa and mPCa suggests biological similarities and historical radiological staging limitations, which warrant further investigation.


Assuntos
Progressão da Doença , Neoplasias da Próstata , Humanos , Masculino , Neoplasias da Próstata/genética , Neoplasias da Próstata/patologia , Neoplasias da Próstata/radioterapia , Idoso , Pessoa de Meia-Idade , Biópsia , Genômica , Próstata/patologia , Metástase Neoplásica , Estudos de Coortes
5.
J Cell Sci ; 135(19)2022 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-36052646

RESUMO

The compartmentalised eukaryotic cell demands accurate targeting of proteins to the organelles in which they function, whether membrane-bound (like the nucleus) or non-membrane-bound (like the nucleolus). Nucleolar targeting relies on positively charged localisation signals and has received rejuvenated interest since the widespread recognition of liquid-liquid phase separation (LLPS) as a mechanism contributing to nucleolus formation. Here, we exploit a new genome-wide analysis of protein localisation in the early-branching eukaryote Trypanosoma brucei to analyse general nucleolar protein properties. T. brucei nucleolar proteins have similar properties to those in common model eukaryotes, specifically basic amino acids. Using protein truncations and addition of candidate targeting sequences to proteins, we show both homopolymer runs and distributed basic amino acids give nucleolar partition, further aided by a nuclear localisation signal (NLS). These findings are consistent with phase separation models of nucleolar formation and physical protein properties being a major contributing mechanism for eukaryotic nucleolar targeting, conserved from the last eukaryotic common ancestor. Importantly, cytoplasmic ribosome proteins, unlike mitochondrial ribosome proteins, have more basic residues - pointing to adaptation of physicochemical properties to assist segregation.


Assuntos
Células Eucarióticas , Sinais de Localização Nuclear , Sequência de Aminoácidos , Aminoácidos Básicos/metabolismo , Nucléolo Celular/metabolismo , Eucariotos/metabolismo , Células Eucarióticas/metabolismo , Sinais de Localização Nuclear/metabolismo , Proteínas Nucleares/metabolismo , Transporte Proteico , Ribossomos/genética , Ribossomos/metabolismo
6.
Psychol Med ; 54(6): 1061-1073, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38174555

RESUMO

The network theory of psychological disorders posits that systems of symptoms cause, or are associated with, the expression of other symptoms. Substantial literature on symptom networks has been published to date, although no systematic review has been conducted exclusively on symptom networks of schizophrenia, schizoaffective disorder, and schizophreniform (people diagnosed with schizophrenia; PDS). This study aims to compare statistics of the symptom network publications on PDS in the last 21 years and identify congruences and discrepancies in the literature. More specifically, we will focus on centrality statistics. Thirty-two studies met the inclusion criteria. The results suggest that cognition, and social, and occupational functioning are central to the network of symptoms. Positive symptoms, particularly delusions were central among participants in many studies that did not include cognitive assessment. Nodes representing cognition were most central in those studies that did. Nodes representing negative symptoms were not as central as items measuring positive symptoms. Some studies that included measures of mood and affect found items or subscales measuring depression were central nodes in the networks. Cognition, and social, and occupational functioning appear to be core symptoms of schizophrenia as they are more central in the networks, compared to variables assessing positive symptoms. This seems consistent despite heterogeneity in the design of the studies.


Assuntos
Transtornos Psicóticos , Esquizofrenia , Humanos , Esquizofrenia/diagnóstico , Transtornos Psicóticos/psicologia , Cognição , Psicologia do Esquizofrênico , Escalas de Graduação Psiquiátrica
7.
J Surg Res ; 295: 723-731, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38142575

RESUMO

INTRODUCTION: Operating room communication is frequently disrupted, raising safety concerns. We used a Speech Interference Instrument to measure the frequency, impact, and causes of speech communication interference (SCI) events. METHODS: In this prospective study, we observed 40 surgeries, primarily general surgery, to measure the frequency of SCI, defined as "group discourse disrupted according to the participants, the goals, or the physical and situational context of the exchange." We performed supplemental observations, focused on conducting postsurgery interviews with SCI event participants to identify contextual factors. We thematically analyzed notes and interviews. RESULTS: The observed 103 SCI events in 40 surgeries (mean 2.58) mostly involved the attending (50.5%), circulating nurse (44.6%), resident (44.6%), or scrub tech (42.7%). The majority (82.1%) of SCI events occurred during another patient-related task. 17.5% occurred at a critical moment. 27.2% of SCI events were not acknowledged or repeated and the message was lost. Including the supplemental observations, 97.0% of SCI events caused a delay (mean 5 s). Inter-rater reliability, calculated by Gwet's AC1 was 0.87-0.98. Postsurgery interviews confirmed miscommunication and distractions. Attention was most commonly diverted by loud noises (e.g., suction), conversations, or multitasking (e.g., using the electronic health record). Successful strategies included repetition or deferment of the request until competing tasks were complete. CONCLUSIONS: Communication interference may have patient safety implications that arise from conflicts with other case-related tasks, machine noises, and other conversations. Reorganization of workflow, tasks, and communication behaviors could reduce miscommunication and improve surgical safety and efficiency.


Assuntos
Salas Cirúrgicas , Fala , Humanos , Estudos Prospectivos , Reprodutibilidade dos Testes , Comunicação , Equipe de Assistência ao Paciente
8.
Biochemistry ; 62(20): 2916-2927, 2023 10 17.
Artigo em Inglês | MEDLINE | ID: mdl-37768194

RESUMO

The P168 and I172 side chains sit at the heart of the active site of triosephosphate isomerase (TIM) and play important roles in the catalysis of the isomerization reaction. The phosphodianion of substrate glyceraldehyde 3-phosphate (GAP) drives a conformational change at the TIM that creates a steric interaction with the P168 side chain that is relieved by the movement of P168 that carries the basic E167 side chain into a clamp that consists of the hydrophobic I172 and L232 side chains. The P168A/I172A substitution at TIM from Trypanosoma brucei brucei (TbbTIM) causes a large 120,000-fold decrease in kcat for isomerization of GAP that eliminates most of the difference in the reactivity of TIM compared to the small amine base quinuclidinone for deprotonation of catalyst-bound GAP. The I172A substitution causes a > 2-unit decrease in the pKa of the E167 carboxylic acid in a complex to the intermediate analog PGA, but the P168A substitution at the I172A variant has no further effect on this pKa. The P168A/I172A substitutions cause a 5-fold decrease in Km for the isomerization of GAP from a 0.9 kcal/mol stabilization of the substrate Michaelis complexes. The results show that the P168 and I172 side chains play a dual role in destabilizing the ground-state Michaelis complex to GAP and in promoting stabilization of the transition state for substrate isomerization. This is consistent with an important role for these side chains in an induced fit reaction mechanism [Richard, J. P. (2022) Enabling Role of Ligand-Driven Conformational Changes in Enzyme Evolution. Biochemistry 61, 1533-1542].


Assuntos
Gliceraldeído 3-Fosfato , Triose-Fosfato Isomerase , Triose-Fosfato Isomerase/química , Domínio Catalítico , Gliceraldeído 3-Fosfato/química , Catálise
9.
Biochemistry ; 62(15): 2314-2324, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37463347

RESUMO

The pressure to optimize enzymatic rate accelerations has driven the evolution of the induced-fit mechanism for enzyme catalysts where the binding interactions of nonreacting phosphodianion or adenosyl substrate pieces drive enzyme conformational changes to form protein substrate cages that are activated for catalysis. We report the results of experiments to test the hypothesis that utilization of the binding energy of the adenosine 5'-diphosphate ribose (ADP-ribose) fragment of the NAD cofactor to drive a protein conformational change activates Candida boidinii formate dehydrogenase (CbFDH) for catalysis of hydride transfer from formate to NAD+. The ADP-ribose fragment provides a >14 kcal/mol stabilization of the transition state for CbFDH-catalyzed hydride transfer from formate to NAD+. This is larger than the ca. 6 kcal/mol stabilization of the ground-state Michaelis complex between CbFDH and NAD+ (KNAD = 0.032 mM). The ADP, AMP, and ribose 5'-phosphate fragments of NAD+ activate CbFDH for catalysis of hydride transfer from formate to nicotinamide riboside (NR). At a 1.0 M standard state, these activators stabilize the hydride transfer transition states by ≈5.5 (ADP), 5.5 (AMP), and 4.4 (ribose 5'-phosphate) kcal/mol. We propose that activation by these cofactor fragments is partly or entirely due to the ion-pair interaction between the guanidino side chain cation of R174 and the activator phosphate anion. This substitutes for the interaction between the α-adenosyl pyrophosphate anion of the whole NAD+ cofactor that holds CbFDH in the catalytically active closed conformation.


Assuntos
Formiato Desidrogenases , NAD , NAD/metabolismo , Formiato Desidrogenases/metabolismo , Ribose , Catálise , Ânions , Fosfatos , Cinética
10.
Biochemistry ; 62(11): 1794-1806, 2023 06 06.
Artigo em Inglês | MEDLINE | ID: mdl-37162263

RESUMO

Four catalytic amino acids at triosephosphate isomerase (TIM) are highly conserved: N11, K13, H95, and E167. Asparagine 11 is the last of these to be characterized in mutagenesis studies. The ND2 side chain atom of N11 is hydrogen bonded to the O-1 hydroxyl of enzyme-bound dihydroxyacetone phosphate (DHAP), and it sits in an extended chain of hydrogen-bonded side chains that includes T75' from the second subunit. The N11A variants of wild-type TIM from Trypanosoma brucei brucei (TbbTIM) and Leishmania mexicana (LmTIM) undergo dissociation from the dimer to monomer under our assay conditions. Values of Kas = 8 × 103 and 1 × 106 M-1, respectively, were determined for the conversion of monomeric N11A TbbTIM and LmTIM into their homodimers. The N11A substitution at the variant of LmTIM previously stabilized by the E65Q substitution gives the N11A/E65Q variant that is stable to dissociation under our assay conditions. The X-ray crystal structure of N11A/E65Q LmTIM shows an active site that is essentially superimposable on that for wild-type TbbTIM, which also has a glutamine at position 65. A comparison of the kinetic parameters for E65Q LmTIM and N11A/E65Q LmTIM-catalyzed reactions of (R)-glyceraldehyde 3-phosphate (GAP) and (DHAP) shows that the N11A substitution results in a (13-14)-fold decrease in kcat/Km for substrate isomerization and a similar decrease in kcat for DHAP but only a 2-fold decrease in kcat for GAP.


Assuntos
Aminoácidos , Triose-Fosfato Isomerase , Triose-Fosfato Isomerase/química , Catálise , Hidrogênio
11.
Lancet ; 399(10330): 1141-1153, 2022 03 19.
Artigo em Inglês | MEDLINE | ID: mdl-35305740

RESUMO

BACKGROUND: We aimed to assess the effectiveness of a single dose of the Ad26.COV2.S vaccine (Johnson & Johnson) in health-care workers in South Africa during two waves of the South African COVID-19 epidemic. METHODS: In the single-arm, open-label, phase 3B implementation Sisonke study, health-care workers aged 18 years and older were invited for vaccination at one of 122 vaccination sites nationally. Participants received a single dose of 5 × 1010 viral particles of the Ad26.COV2.S vaccine. Vaccinated participants were linked with their person-level data from one of two national medical insurance schemes (scheme A and scheme B) and matched for COVID-19 risk with an unvaccinated member of the general population. The primary outcome was vaccine effectiveness against severe COVID-19, defined as COVID-19-related admission to hospital, hospitalisation requiring critical or intensive care, or death, in health-care workers compared with the general population, ascertained 28 days or more after vaccination or matching, up to data cutoff. This study is registered with the South African National Clinical Trial Registry, DOH-27-022021-6844, ClinicalTrials.gov, NCT04838795, and the Pan African Clinical Trials Registry, PACTR202102855526180, and is closed to accrual. FINDINGS: Between Feb 17 and May 17, 2021, 477 102 health-care workers were enrolled and vaccinated, of whom 357 401 (74·9%) were female and 119 701 (25·1%) were male, with a median age of 42·0 years (33·0-51·0). 215 813 vaccinated individuals were matched with 215 813 unvaccinated individuals. As of data cutoff (July 17, 2021), vaccine effectiveness derived from the total matched cohort was 83% (95% CI 75-89) to prevent COVID-19-related deaths, 75% (69-82) to prevent COVID-19-related hospital admissions requiring critical or intensive care, and 67% (62-71) to prevent COVID-19-related hospitalisations. The vaccine effectiveness for all three outcomes were consistent across scheme A and scheme B. The vaccine effectiveness was maintained in older health-care workers and those with comorbidities including HIV infection. During the course of the study, the beta (B.1.351) and then the delta (B.1.617.2) SARS-CoV-2 variants of concerns were dominant, and vaccine effectiveness remained consistent (for scheme A plus B vaccine effectiveness against COVID-19-related hospital admission during beta wave was 62% [95% CI 42-76] and during delta wave was 67% [62-71], and vaccine effectiveness against COVID-19-related death during beta wave was 86% [57-100] and during delta wave was 82% [74-89]). INTERPRETATION: The single-dose Ad26.COV2.S vaccine shows effectiveness against severe COVID-19 disease and COVID-19-related death after vaccination, and against both beta and delta variants, providing real-world evidence for its use globally. FUNDING: National Treasury of South Africa, the National Department of Health, Solidarity Response Fund NPC, The Michael & Susan Dell Foundation, The Elma Vaccines and Immunization Foundation, and the Bill & Melinda Gates Foundation.


Assuntos
COVID-19 , Infecções por HIV , Vacinas , Ad26COVS1 , Adolescente , Adulto , Idoso , COVID-19/epidemiologia , COVID-19/prevenção & controle , Feminino , Humanos , Masculino , SARS-CoV-2 , África do Sul/epidemiologia
12.
J Exp Bot ; 74(21): 6773-6789, 2023 11 21.
Artigo em Inglês | MEDLINE | ID: mdl-37658791

RESUMO

Phytoplankton are exposed to dramatic variations in light quality when cells are carried by upwelling or downwelling currents or encounter sediment. We investigated the potential impact of light quality changes in Ostreococcus, a key marine photosynthetic picoeukaryote, by analysing changes in its transcriptome, pigment content, and photophysiology after acclimation to monochromatic red, green, or blue light. The clade B species RCC809, isolated from the deep euphotic zone of the tropical Atlantic Ocean, responded to blue light by accelerating cell division at the expense of storage reserves and by increasing the relative level of blue-light-absorbing pigments. It responded to red and green light by increasing its potential for photoprotection. In contrast, the clade A species OTTH0595, which originated from a shallow water environment, showed no difference in photosynthetic properties and minor differences in carotenoid contents between light qualities. This was associated with the loss of candidate light-quality responsive promoter motifs identified in RCC809 genes. These results demonstrate that light quality can have a major influence on the physiology of eukaryotic phytoplankton and suggest that different light quality environments can drive selection for diverse patterns of responsiveness and environmental niche partitioning.


Assuntos
Clorófitas , Ecótipo , Clorófitas/genética , Fotossíntese , Fitoplâncton/genética , Oceanos e Mares
13.
Chemistry ; 29(60): e202301852, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37505481

RESUMO

The recent disclosure of the ability of aromatic isocyanides to harvest visible light and act as single electron acceptors when reacting with tertiary aromatic amines has triggered a renewed interest in their application to the development of green photoredox catalytic methodologies. Accordingly, the present work explores their ability to promote the generation of both alkyl and acyl radicals starting from radical precursors such as Hantzsch esters, potassium alkyltrifluoroborates, and α-oxoacids. Mechanistic studies involving UV-visible absorption and fluorescence experiments, electrochemical measurements of the ground-state redox potentials along with computational calculations of both the ground- and the excited-state redox potentials of a set of nine different aromatic isocyanides provide key insights to promote a rationale design of a new generation of isocyanide-based organic photoredox catalysts. Importantly, the green potential of the investigated chemistry is demonstrated by a direct and easy access to deuterium labeled compounds.

14.
Pediatr Res ; 94(4): 1436-1443, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37188799

RESUMO

BACKGROUND: Hypoxemia is a physiological manifestation of immature respiratory control in preterm neonates, which is likely impacted by neurotransmitter imbalances. We investigated relationships between plasma levels of the neurotransmitter serotonin (5-HT), metabolites of tryptophan (TRP), and parameters of hypoxemia in preterm neonates. METHODS: TRP, 5-HT, 5-hydroxyindoleacetic acid (5-HIAA), and kynurenic acid (KA) were analyzed in platelet-poor plasma at ~1 week and ~1 month of life from a prospective cohort of 168 preterm neonates <31 weeks gestational age (GA). Frequency of intermittent hypoxemia (IH) events and percent time hypoxemic (<80%) were analyzed in a 6 h window after the blood draw. RESULTS: At 1 week, infants with detectable plasma 5-HT had fewer IH events (OR (95% CI) = 0.52 (0.29, 0.31)) and less percent time <80% (OR (95% CI) = 0.54 (0.31, 0.95)) compared to infants with undetectable 5-HT. A similar relationship occurred at 1 month. At 1 week, infants with higher KA showed greater percent time <80% (OR (95% CI) = 1.90 (1.03, 3.50)). TRP, 5-HIAA or KA were not associated with IH frequency at either postnatal age. IH frequency and percent time <80% were positively associated with GA < 29 weeks. CONCLUSIONS: Circulating neuromodulators 5-HT and KA might represent biomarkers of immature respiratory control contributing to hypoxemia in preterm neonates. IMPACT: Hypoxemia events are frequent in preterm infants and are associated with poor outcomes. Mechanisms driving hypoxemia such as immature respiratory control may include central and peripheral imbalances in modulatory neurotransmitters. This study found associations between the plasma neuromodulators serotonin and kynurenic acid and parameters of hypoxemia in preterm neonates. Imbalances in plasma biomarkers affecting respiratory control may help identify neonates at risk of short- and long-term adverse outcomes.


Assuntos
Recém-Nascido Prematuro , Serotonina , Lactente , Humanos , Recém-Nascido , Serotonina/metabolismo , Estudos Prospectivos , Ácido Hidroxi-Indolacético , Ácido Cinurênico , Hipóxia , Triptofano , Biomarcadores , Neurotransmissores
15.
Postgrad Med J ; 99(1174): 849-854, 2023 Jul 21.
Artigo em Inglês | MEDLINE | ID: mdl-37137566

RESUMO

INTRODUCTION: This study aimed to evaluate differential attainment during higher surgical training (HST; all specialties) related to three ethnic cohorts: White UK (WUKG), Black and Minority Ethnic UK Graduates (BMEUKG), and International Medical Graduates (IMG). METHOD: Anonymised records of 266 HSTs (126 WUKG, 65 BMEUKG, 75 IMG; 7 years) in a single UK Statutory Education Body were examined. Primary effect measures were Annual Record of Competency Progression Outcome (ARCPO) and Fellowship of the Royal College of Surgeons (FRCS) pass. RESULTS: ARCPOs related to ethnicity and specialty were similar with the exception of general surgery (GS) trainees, four of whom received ARCPO 4 (GS 4.9% (75% BME; p=0.025) vs all other 0%). ARCPO 3 was commoner in women (22/76, (28.9%) than men 27/190 (14.2%), OR 2.46, p=0.006). FRCS pass rates (WUKG vs BMEUKG vs IMG) were 76.9%, 52.9% and 53.9% respectively (p=0.064) but unrelated to gender (M 70.4% vs F 64.3%). On multivariable analyses: ARCPO 3 was associated with Female gender and Maternity Leave (OR 8.05, p=0.001); FRCS pass with ethnicity (OR 0.21, p=0.028) and Hirsch Indices of ≥5 (OR 11.17, p=0.001). CONCLUSION: Differential attainment was plain with BMEUKG FRCS performance almost a third poorer than WUKG, and women twofold more likely to receive adverse ARCPOs, with return from statutory leave independently associated with training extension. Focused counter measures targeted at non-operative technical skills (including academic reach), Keeping in Touch, Return to Work, and re-induction programmed support are urgently needed for trainees at risk.


Assuntos
Medicina , Cirurgiões , Gravidez , Masculino , Humanos , Feminino , Educação de Pós-Graduação em Medicina , Etnicidade , Avaliação Educacional , Competência Clínica , Reino Unido
16.
Sensors (Basel) ; 24(1)2023 Dec 27.
Artigo em Inglês | MEDLINE | ID: mdl-38203005

RESUMO

Growing pumpkins in controlled environments, such as greenhouses, has become increasingly important due to the potential to optimise yield and quality. However, achieving optimal environmental conditions for pumpkin cultivation requires precise monitoring and control, which can be facilitated by modern sensor technologies. The objective of this study was to determine the optimal placement of sensors to determine the influence of external parameters on the maturity of pumpkins. The greenhouse used in the study consisted of a plastic film for growing pumpkins. Five different sensors labeled from A1 to A5 measured the air temperature, humidity, soil temperature, soil humidity, and illumination at five different locations. We used two methods, error-based sensor placement and entropy-based sensor placement, to evaluate optimisation. We selected A3 sensor locations where the monitored data were close to the reference value, i.e., the average data of all measurement locations and parameters. Using this method, we selected sensor positions to monitor the influence of external parameters on the maturity of pumpkins. These methods enable the determination of optimal sensor locations to represent the entire facility environment and detect areas with significant environmental disparities. Our study provides an accurate measurement of the internal environment of a greenhouse and properly selects the base installation locations of sensors in the pumpkin greenhouse.


Assuntos
Cucurbita , Entropia , Ambiente Controlado , Umidade , Solo
17.
J ECT ; 39(2): 106-110, 2023 06 01.
Artigo em Inglês | MEDLINE | ID: mdl-36318226

RESUMO

OBJECTIVE: The aims of this study were to compare threshold and suprathreshold ictal electroencephalograms (EEGs) in right unilateral (RUL) ultrabrief (UB) electroconvulsive therapy (ECT) and to identify the differences between these EEGs. METHODS: This study is a retrospective review of 125 pairs EEGs from titration and subsequent sessions across a 2-year period. All EEGs were independently rated for by 2 assessors using a scale based on qualities of an EEG used to guide ECT treatment dose adequacy, for example, midictal amplitude, regularity, interhemispheric coherence, seizure end point, and postictal suppression. The scores of threshold and suprathreshold EEGs were compared within and between groups based on 2 ECT types, that is, RUL UB ECT and RUL brief pulse (BP) ECT. RESULTS: Paired t tests showed a statistically significant difference in between threshold and suprathreshold EEG scores in RUL UB ECT. There were no statistically significant differences between corresponding scores for RUL UB ECT and RUL BP ECT threshold and suprathreshold EEGs. CONCLUSIONS: There is a significant difference between the quality of threshold and suprathreshold EEGs in RUL UB ECT when measured with an EEG rating scale. Visual rating of ictal EEGs is as reliable in discriminating between threshold and suprathreshold seizure in RUL UB ECT as it is in RUL BP ECT.


Assuntos
Eletroconvulsoterapia , Humanos , Resultado do Tratamento , Eletroencefalografia , Convulsões , Estudos Retrospectivos
18.
J Clin Ultrasound ; 51(1): 5-15, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-35788941

RESUMO

PURPOSE: Exercise intolerance is a common complication in survivors of allogeneic hematopoietic stem-cell transplantation (allo-HSCT). The aim of this study was to determine if cardiac function measured with echocardiography is associated with exercise capacity measured with cardio-pulmonary exercise tests in long-term survivors treated in their youth with allo-HSCT. METHODS: The study included 96 patients, of which 54.2% were female, aged 34.9 ± 11.6 years and 17.7 ± 9.3 years after allo-HSCT. Reduced exercise capacity was defined as <85% of predicted-peak oxygen uptake (VO2peak ). Linear regression was used in the prediction of VO2peak (ml/kg/min). Receiver operating characteristic evaluated the accuracy of predicting reduced exercise capacity. RESULTS: VO2peak was 36.2 ± 7.7 ml/kg/min and 43 (44.8%) had reduced exercise capacity. Left ventricular ejection fraction was 55.4 ± 5.9% and global longitudinal strain (GLS) was -17.6% ± 2.0%. Left and right ventricular functions were significantly lower in survivors with reduced exercise capacity. Increased body mass index, lower physical activity score, reduced pulmonary function (by forced expiratory volume in 1-s) and reduced left ventricular systolic function (by GLS) were significant independent predictors for reduced VO2peak . GLS was superior to other echocardiographical indices for identifying reduced exercise capacity (area under curve = 0.64, p = 0.014). CONCLUSIONS: Left ventricular systolic dysfunction measured by GLS is associated with reduced exercise capacity in long-term allo-HSCT survivors.


Assuntos
Transplante de Células-Tronco Hematopoéticas , Disfunção Ventricular Esquerda , Adolescente , Humanos , Feminino , Masculino , Função Ventricular Esquerda , Volume Sistólico/fisiologia , Tolerância ao Exercício , Disfunção Ventricular Esquerda/diagnóstico por imagem , Transplante de Células-Tronco Hematopoéticas/efeitos adversos , Sobreviventes
19.
Int J Mol Sci ; 24(18)2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37762100

RESUMO

Salinity influences the level of antioxidants and proline content, which are both involved in the regulation of stress responses in plants. To examine the interplay between the antioxidant system and proline metabolism in plant stress acclimation, explants of Lycium ruthenicum were subjected to NaCl treatments, and the growth characteristics, antioxidant enzyme activities, proline accumulation, and metabolic enzyme content were analyzed. The results revealed that NaCl concentrations between 50 to 150 mM have a positive effect on the growth of L. ruthenicum explants. Increasing NaCl concentrations elevated the activities of superoxide dismutase (SOD) and catalase (CAT), while hydrogen peroxide (H2O2) content was inhibited, suggesting that the elevated antioxidants play a central protective role in superoxide anion (O2•-) and H2O2 scavenging processes in response to NaCl treatments. Also, high proline levels also protect antioxidant enzyme machinery, thus protecting the plants from oxidative damage and enhancing osmotic adjustment. Increasing levels of pyrroline-5-carboxylate synthetase (P5CS), pyrroline-5-carboxylate reductase (P5CR), and ornithine-δ-aminotransferase (δ-OAT) were observed, resulting in elevated level of proline. In addition, the expression levels of LrP5CS1, -2, -3, LrOAT-1, and -2 were promoted in NaCl treatments. According to the combined analysis of metabolic enzyme activities and their relative expression, it is confirmed that the glutamate (Glu) pathway is activated in L. ruthenicum faced with different levels of NaCl concentrations. However, Glu supplied by δ-OAT is fed back into the main pathway for proline metabolism.

20.
J Foot Ankle Surg ; 62(2): 382-387, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36335050

RESUMO

The uninjured contralateral feet of consecutive patients undergoing cone-beam weightbearing computed tomography for acute Lisfranc injury between July 2017 and October 2019 were retrospectively analyzed. Of these, any cases with history or radiological evidence of trauma to the Lisfranc interval were excluded. The area of the non-weightbearing (NWBA) and weightbearing (WBA) Lisfranc joint was calculated (in mm2) using a novel technique. Area difference (AD) was calculated as WBA-NWBA. Area ratio (AR) was calculated as WBA/NWBA. A subset of cases was double-measured by 2 technologists to evaluate inter- and intraobserver variability. A total of 91 patients aged 15 to 74 years were included in the study. The measurement technique was reproducible with excellent intraobserver correlation (intraclass correlation coefficient [ICC]: 0.998, 95% confidence interval [CI]: 0.996-0.999) and high interobserver correlation (ICC: 0.964, CI: 0.939-0.979). The median NWBA was 83 (range 52-171) and median WBA was 86 (range 52-171). Median AD was 1 mm2 (range -3 to 10) and median AR was 1.01 (range 0.96-1.11). No significant difference was identified in AD or AR when adjusted for age, gender, patient-weight or weight put through the foot. Both AD and AR distributions were highly skewed toward 0 and 1, respectively. Based on 95% CI, normal reference range for AD is -1 to 7 mm2 and for AR is 0.98 to 1.09. Absolute area of the Lisfranc joint is highly variable between individuals. The Lisfranc joint is rigid with little to no physiologic widening in most subjects. The normal upper limit of widening of the Lisfranc area on weightbearing was 9%. Differences in age, sex, patient-weight or weight put through the foot were not significantly associated with the extent of joint widening.


Assuntos
, Tomografia Computadorizada por Raios X , Adulto , Humanos , Valores de Referência , Estudos Retrospectivos , Tomografia Computadorizada por Raios X/métodos , Radiografia , Suporte de Carga
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