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1.
BMJ Open Respir Res ; 11(1)2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38749534

RESUMO

INTRODUCTION: Early enteral nutrition (EN) in critically ill adult patients is thought to improve mortality and morbidity; expert guidelines recommend early initiation of EN in critically ill adults. However, the ideal schedule and dose of EN remain understudied. STUDY OBJECTIVE: Our objective was to evaluate the relationship between achieving 70% of recommended EN within 2 days of intubation ('early goal EN') and clinical outcomes in mechanically ventilated medically critically ill adults. We hypothesised that early goal EN would be associated with reduced in-hospital death. METHODS: We conducted a retrospective cohort study of mechanically ventilated adult patients admitted to our medical intensive care unit during 2013-2019. We assessed the proportion of recommended total EN provided to the patient each day following intubation until extubation, death or 7 days whichever was shortest. Patients who received 70% or more of their recommended total daily EN within 2 days of intubation (ie, 'baseline period') were considered to have achieved 'early goal EN'; these patients were compared with patients who did not ('low EN'). The primary outcome was in-hospital death; secondary outcomes were successful extubation and discharge alive. RESULTS: 938 patients met eligibility criteria and survived the baseline period. During the 7-day postintubation period, 64% of all patients reached 70% of recommended daily calories; 33% of patients achieved early goal EN. In unadjusted and adjusted models, early goal EN versus low EN was associated with a lower incidence of in-hospital death (subdistribution HR (SHR) unadjusted=0.63, p=0.0003, SHR adjusted=0.73, p=0.02). Early goal EN was also associated with a higher incidence of successful extubation (SHR unadjusted=1.41, p<0.00001, SHR adjusted=1.27, p=0.002) and discharge alive (SHR unadjusted=1.54, p<0.00001, SHR adjusted=1.24, p=0.02). CONCLUSIONS: Early goal EN was associated with significant improvement in clinical metrics of decreased in-hospital death, increased extubation and increased hospital discharge alive.


Assuntos
Estado Terminal , Nutrição Enteral , Mortalidade Hospitalar , Respiração Artificial , Humanos , Estudos Retrospectivos , Estado Terminal/mortalidade , Estado Terminal/terapia , Masculino , Nutrição Enteral/métodos , Respiração Artificial/estatística & dados numéricos , Feminino , Pessoa de Meia-Idade , Idoso , Unidades de Terapia Intensiva , Fatores de Tempo
2.
Proc Natl Acad Sci U S A ; 121(20): e2400689121, 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38717858

RESUMO

Social reputations facilitate cooperation: those who help others gain a good reputation, making them more likely to receive help themselves. But when people hold private views of one another, this cycle of indirect reciprocity breaks down, as disagreements lead to the perception of unjustified behavior that ultimately undermines cooperation. Theoretical studies often assume population-wide agreement about reputations, invoking rapid gossip as an endogenous mechanism for reaching consensus. However, the theory of indirect reciprocity lacks a mechanistic description of how gossip actually generates consensus. Here, we develop a mechanistic model of gossip-based indirect reciprocity that incorporates two alternative forms of gossip: exchanging information with randomly selected peers or consulting a single gossip source. We show that these two forms of gossip are mathematically equivalent under an appropriate transformation of parameters. We derive an analytical expression for the minimum amount of gossip required to reach sufficient consensus and stabilize cooperation. We analyze how the amount of gossip necessary for cooperation depends on the benefits and costs of cooperation, the assessment rule (social norm), and errors in reputation assessment, strategy execution, and gossip transmission. Finally, we show that biased gossip can either facilitate or hinder cooperation, depending on the direction and magnitude of the bias. Our results contribute to the growing literature on cooperation facilitated by communication, and they highlight the need to study strategic interactions coupled with the spread of social information.


Assuntos
Comportamento Cooperativo , Humanos , Comunicação , Relações Interpessoais , Modelos Teóricos
3.
Allergy Asthma Proc ; 45(3): 207-210, 2024 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-38755784

RESUMO

Background: ß-Lactam antibiotics are widely used with increased utilization in hospitalized patients. Of this population, as high as 10-20% report an allergy to ß-lactam antibiotics but <5% are at risk of developing clinically significant immunoglobulin E- or T-lymphocyte-mediated reactions. Most of the time, these reported allergies are present during an illness with no previous inquiry of their validity, which makes investigation and possible removal of this allergy label a challenge. Methods: We report a 16-year-old boy who presented with 1 week of night sweats, chills, headaches, and fatigue, followed by 1 day of fever and right knee swelling and who was diagnosed with septic bursitis. Due to concern of a penicillin allergy label, the patient was started on a cefepime infusion. Five minutes into the infusion, the patient reported puffy eyes and itchy throat, followed by a witnessed cascading flat nonpruritic erythematous rash from head to shoulders. This rash went away in 3 minutes after stopping the infusion and the patient being given 50 mg of intravenous diphenhydramine and 10 mg of oral dexamethasone. He was subsequently diagnosed with a cefepime allergy. Results: Allergy/immunology was the speciality consulted, and, by using a screening questionnaire, the patient's reported penicillin allergy was determined to be low risk. Subsequent 1-step oral challenge was the key to providing the patient with the necessary antibiotic course to resolve his infection. Conclusion: Multiple reported antibiotic allergies lead to poor antibiotic stewardship that causes impactful health and financial burden on the patient and health-care system. It is thus important to have an evidence-based systematic approach to de-label penicillin antibiotic allergy labels to reduce these potential harms.


Assuntos
Antibacterianos , Cefalosporinas , Hipersensibilidade a Drogas , Penicilinas , Humanos , Masculino , Hipersensibilidade a Drogas/diagnóstico , Hipersensibilidade a Drogas/etiologia , Adolescente , Penicilinas/efeitos adversos , Antibacterianos/efeitos adversos , Cefalosporinas/efeitos adversos , Rotulagem de Medicamentos , Alérgenos/imunologia , Hospitalização , Cefepima/efeitos adversos
4.
J Morphol ; 285(5): e21705, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38704727

RESUMO

The ontogeny of feeding is characterized by shifting functional demands concurrent with changes in craniofacial anatomy; relationships between these factors will look different in primates with disparate feeding behaviors during development. This study examines the ontogeny of skull morphology and jaw leverage in tufted (Sapajus) and untufted (Cebus) capuchin monkeys. Unlike Cebus, Sapajus have a mechanically challenging diet and behavioral observations of juvenile Sapajus suggest these foods are exploited early in development. Landmarks were placed on three-dimensional surface models of an ontogenetic series of Sapajus and Cebus skulls (n = 53) and used to generate shape data and jaw-leverage estimates across the tooth row for three jaw-closing muscles (temporalis, masseter, medial pterygoid) as well as a weighted combined estimate. Using geometric morphometric methods, we found that skull shape diverges early and shape is significantly different between Sapajus and Cebus throughout ontogeny. Additionally, jaw leverage varies with age and position on the tooth row and is greater in Sapajus compared to Cebus when calculated at the permanent dentition. We used two-block partial least squares analyses to identify covariance between skull shape and each of our jaw muscle leverage estimates. Sapajus, but not Cebus, has significant covariance between all leverage estimates at the anterior dentition. Our findings show that Sapajus and Cebus exhibit distinct craniofacial morphologies early in ontogeny and strong covariance between leverage estimates and craniofacial shape in Sapajus. These results are consistent with prior behavioral and comparative work suggesting these differences are a function of selection for exploiting mechanically challenging foods in Sapajus, and further emphasize that these differences appear quite early in ontogeny. This research builds on prior work that has highlighted the importance of understanding ontogeny for interpreting adult morphology.


Assuntos
Cebus , Arcada Osseodentária , Crânio , Animais , Crânio/anatomia & histologia , Crânio/crescimento & desenvolvimento , Arcada Osseodentária/anatomia & histologia , Cebus/anatomia & histologia , Sapajus/anatomia & histologia , Sapajus/crescimento & desenvolvimento , Comportamento Alimentar/fisiologia , Masculino , Feminino
5.
Eur J Nutr ; 2024 May 07.
Artigo em Inglês | MEDLINE | ID: mdl-38714546

RESUMO

PURPOSE: We aimed to examine the association between dietary patterns and type 2 diabetes mellitus (T2DM) while considering the potential effect modification by metabolic phenotypes (metabotypes). Additionally, we aimed to explore the association between dietary scores and prediabetes. METHODS: A total of 1460 participants (11.8% with T2DM) from the cross-sectional population-based KORA FF4 study were included. Participants, classified into three metabotype subgroups, had both their FSAm-NPS dietary index (underpinning the Nutri-Score) and ultra-processed foods (UPF) intake (using NOVA classification) calculated. Glucose tolerance status was assessed via oral glucose tolerance tests (OGTT) in non-diabetic participants and was classified according to the American Diabetes Association criteria. Logistic regression models were used for both the overall and metabotype-stratified analyses of dietary scores' association with T2DM, and multinomial probit models for their association with prediabetes. RESULTS: Participants who had a diet with a higher FSAm-NPS dietary index (i.e., a lower diet quality) or a greater percentage of UPF consumption showed a positive association with T2DM. Stratified analyses demonstrated a strengthened association between UPF consumption and T2DM specifically in the metabolically most unfavorable metabotype (Odds Ratio, OR 1.92; 95% Confidence Interval, CI 1.35, 2.73). A diet with a higher FSAm-NPS dietary index was also positively associated with prediabetes (OR 1.19; 95% CI 1.04, 1.35). CONCLUSION: Our study suggests different associations between poorer diet quality and T2DM across individuals exhibiting diverse metabotypes, pointing to the option for stratified dietary interventions in diabetes prevention.

6.
J Morphol ; 285(5): e21699, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38715161

RESUMO

In 1974, Sue Herring described the relationship between two important performance variables in the feeding system, bite force and gape. These variables are inversely related, such that, without specific muscular adaptations, most animals cannot produce high bite forces at large gapes for a given sized muscle. Despite the importance of these variables for feeding biomechanics and functional ecology, the paucity of in vivo bite force data in primates has led to bite forces largely being estimated through ex vivo methods. Here, we quantify and compare in vivo bite forces and gapes with output from simulated musculoskeletal models in two craniofacially distinct strepsirrhines: Eulemur, which has a shorter jaw and slower chewing cycle durations relative to jaw length and body mass compared to Varecia. Bite forces were collected across a range of linear gapes from 16 adult lemurs (suborder Strepsirrhini) at the Duke Lemur Center in Durham, North Carolina representing three species: Eulemur flavifrons (n = 6; 3F, 3M), Varecia variegata (n = 5; 3F, 2M), and Varecia rubra (n = 5; 5F). Maximum linear and angular gapes were significantly higher for Varecia compared to Eulemur (p = .01) but there were no significant differences in recorded maximum in vivo bite forces (p = .88). Simulated muscle models using architectural data for these taxa suggest this approach is an accurate method of estimating bite force-gape tradeoffs in addition to variables such as fiber length, fiber operating range, and gapes associated with maximum force. Our in vivo and modeling data suggest Varecia has reduced bite force capacities in favor of absolutely wider gapes compared to Eulemur in relation to their longer jaws. Importantly, our comparisons validate the simulated muscle approach for estimating bite force as a function of gape in extant and fossil primates.


Assuntos
Força de Mordida , Animais , Fenômenos Biomecânicos , Arcada Osseodentária/anatomia & histologia , Arcada Osseodentária/fisiologia , Lemur/fisiologia , Lemur/anatomia & histologia , Mastigação/fisiologia , Masculino , Feminino
7.
Psychol Assess ; 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709629

RESUMO

Recent changes to diagnostic criteria for serious conduct problems in children and adolescents have included the presence of elevated callous-unemotional traits to define etiologically and clinically important subgroups of youth with a conduct problem diagnosis. The Clinical Assessment of Prosocial Emotions (CAPE) is an intensive assessment of the symptoms of this limited prosocial emotions specifier that uses a structured professional judgment method of scoring, which may make it useful in clinical settings when diagnoses may require more information than that provided by behavior rating scales. The present study adds to the limited tests of the CAPE's reliability and validity, using a sample of clinic-referred children ages 6-17 years of age, who were all administered the CAPE by trained clinicians. The mean age of the sample was 10.13 years (SD = 2.64); 54% of the sample identified as male and 46% identified as female; and 67% of participants identified as White, 29% identified as Black, and 52% identified as another race/ethnicity (i.e., Asian, Hispanic/Latinx, or other). The findings indicated that CAPE scores demonstrated strong interrater reliability. The scores also were associated with measures of conduct problems and aggression, even when controlling for behavior ratings of callous-unemotional traits. Further, when children with conduct problem diagnoses were divided into groups based on the presence of the limited prosocial emotions specifier from the CAPE, the subgroup with the specifier showed more severe conduct problems and aggression. The results support cautious clinical use of the CAPE, its further development and testing, and research into ways to make its use feasible in many clinical settings. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

8.
Urology ; 2024 May 14.
Artigo em Inglês | MEDLINE | ID: mdl-38754790

RESUMO

OBJECTIVE: To compare early urethroplasty outcomes in non-obese, obese and morbidly obese patients undergoing urethroplasty for urethral stricture disease. The impact of obesity on outcomes is poorly understood but will be increasingly important as obesity continues to rise. METHODS: Patients underwent urethroplasty at one of five institutions between January 2016 and December 2020. Obese (BMI 30-39.9, n=72) and morbidly obese (BMI > 40, n=49) patients were compared to normal weight (BMI <25, n = 29) and overweight (BMI 25-29.9, n=51) patients. Demographics, comorbidities, and stricture characteristics were collected. Outcomes including complications, recurrence, and secondary interventions were compared using univariate and multivariate analysis. RESULTS: 201 patients (Mean BMI 34.1, Range 18.4-65.2) with mean age 52.2 years (SD=17.2) were analyzed. Median follow-up time was 3.71 months. Obese patients were younger (p=0.008), had more anterior (p<0.001), iatrogenic and LS-associated strictures (p=0.036). 60-day complication rate was 26.3% with no differences between cohorts (p= 0.788). 9.5% of patients had extravasation at catheter removal, 18.9% reported stricture recurrence, and 7.4% required additional interventions. Obese patients had greater estimated blood loss (p=0.001) and length of stay (p=0.001). On multivariate analysis, smoking associated with contrast leak (OR 7.176, 95% CI 1.13-45.5) but not recurrence or need for intervention (p=0.155, 0.927). CONCLUSIONS: Obese patients in our cohort had more anterior, iatrogenic, and LS-related strictures. However, obesity is not associated with complications, contrast leak, secondary interventions, or recurrence. Obese had higher blood loss and length of stay. Urethroplasty is safe and effective in obese patients.

9.
Brain ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38739752

RESUMO

Aggregation of the RNA-binding protein TAR DNA binding protein (TDP-43) is a hallmark of TDP-proteinopathies including amyotrophic lateral sclerosis (ALS) and frontotemporal dementia (FTD). As TDP-43 aggregation and dysregulation are causative of neuronal death, there is a special interest in targeting this protein as a therapeutic approach. Previously, we found that TDP-43 extensively co-aggregated with the dual function protein GEF (guanine exchange factor) and RNA-binding protein rho guanine nucleotide exchange factor (RGNEF) in ALS patients. Here, we show that an N-terminal fragment of RGNEF (NF242) interacts directly with the RNA recognition motifs of TDP-43 competing with RNA and that the IPT/TIG domain of NF242 is essential for this interaction. Genetic expression of NF242 in a fruit fly ALS model overexpressing TDP-43 suppressed the neuropathological phenotype increasing lifespan, abolishing motor defects and preventing neurodegeneration. Intracerebroventricular injections of AAV9/NF242 in a severe TDP-43 murine model (rNLS8) improved lifespan and motor phenotype, and decreased neuroinflammation markers. Our results demonstrate an innovative way to target TDP-43 proteinopathies using a protein fragment with a strong affinity for TDP-43 aggregates and a mechanism that includes competition with RNA sequestration, suggesting a promising therapeutic strategy for TDP-43 proteinopathies such as ALS and FTD.

10.
Child Adolesc Psychiatry Ment Health ; 18(1): 46, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38566202

RESUMO

BACKGROUND: Anxiety and depressive disorders typically emerge in adolescence and can be chronic and disabling if not identified and treated early. School-based universal mental health screening may identify young people in need of mental health support and facilitate access to treatment. However, few studies have assessed the potential harms of this approach. This paper examines some of the potential mental health-related harms associated with the universal screening of anxiety and depression administered in Australian secondary schools. METHODS: A total of 1802 adolescent students from 22 secondary schools in New South Wales, Australia, were cluster randomised (at the school level) to receive either an intensive screening procedure (intervention) or a light touch screening procedure (control). Participants in the intensive screening condition received supervised self-report web-based screening questionnaires for anxiety, depression and suicidality with the follow-up care matched to their symptom severity. Participants in the light touch condition received unsupervised web-based screening for anxiety and depression only, followed by generalised advice on help-seeking. No other care was provided in this condition. Study outcomes included the increased risk of anxiety, depression, psychological distress, decreased risk of help-seeking, increased risk of mental health stigma, determined from measures assessed at baseline, 6 weeks post-baseline, and 12 weeks post-baseline. Differences between groups were analysed using mixed effect models. RESULTS: Participants in the intensive screening group were not adversely affected when compared to the light touch screening condition across a range of potential harms. Rather, participants in the intensive screening group were found to have a decreased risk of inhibited help-seeking behaviour compared to the light touch screening condition. CONCLUSIONS: The intensive screening procedure did not appear to adversely impact adolescents' mental health relative to the light touch procedure. Future studies should examine other school-based approaches that may be more effective and efficient than universal screening for reducing mental health burden among students. Trial registration Australian and New Zealand Clinical Trials Registry (ACTRN12618001539224) https://anzctr.org.au/Trial/Registration/TrialReview.aspx?id=375821 .

12.
Phys Chem Chem Phys ; 26(16): 12510-12519, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38619071

RESUMO

The addition of sp-carbon-containing molecules to polycyclic sp3 tetrahedrane (c-C4H4) results in the formation of both o-benzyne (c-C6H4) and benzene (c-C6H6). Since both c-C6H4 and c-C6H6 have been detected in the interstellar medium (ISM), providing additional pathways for their possible astrochemical formation mechanisms can lead to the discovery of other molecules, such as c-C4H4, benzvalyne, and vinylidene (:CCH2). Addition of diatomic carbon (C2), the ethynyl radical (C2H), vinylidene, and acetylene (HCCH) to c-C4H4 is undertaken in individual pathways through high-level quantum chemical computations at the CCSD(T)-F12b/cc-pVTZ-F12 level of theory. The resulting C2 addition pathway proceeds barrierlessly through benzvalyne as an intermediate and reaches a true minimum at c-C6H4, but no leaving groups are produced which is required to dissipate excess energy within an interstellar chemical scheme. Similarly, the C2H addition to c-C4H4 produces benzvalyne as well as its related isomers. This pathway allows for the loss of a hydrogen leaving group to dissipate the resulting energy. Lastly, the HCCH and :CCH2 addition pathways follow through both benzvalene and benzvalyne in order to reach c-C6H6 (benzene) and c-C6H4 (o-benzyne) as well as H2 as the required leaving group. Although there is a barrier to the HCCH addition, the :CCH2 addition presents the contrary with only submerged barriers. These proposed mechanisms provide alternative possibilities for the formation of complex organic molecules in space.

13.
Sci Total Environ ; : 172705, 2024 Apr 24.
Artigo em Inglês | MEDLINE | ID: mdl-38670381

RESUMO

Rivers are increasingly used as superhighways for the continental-scale transportation of freight goods, but the ecological impact of large vessel traffic on river ecosystems is difficult to study. Recently, the temporary maintenance closure of lock and dam systems on the Illinois Waterway (USA) brought commercial vessel traffic to a halt along the river's length, offering a rare opportunity to study the response of the ecosystem before, during, and after an extended pause of this persistent anthropogenic disturbance. We observed improvements in main- and side-channel water quality and a redistribution of fish habitat-use during a months-long, near-complete reduction of large vessel traffic. Over 3600 water quality and 1300 fish community samples indicate that large vessel traffic reduction coincided with a 33 % reduction in turbidity as well as increased use of sampling strata near vessel navigation corridors by sound-sensitive and rheophilic fishes. Gizzard shad (Dorosoma cepedianum), the most abundant species in the system, also expanded their use of these 'impact' areas. Though inland waterway transport is an economically- and climate-friendly alternative to trucking and rail for the shipment of freight, our data suggest that intense vessel traffic may have profound physical and biological impacts across a large river. Monitoring and mitigation of ecological impacts of the ongoing expansion of inland waterway transport around the world will be critical to balancing large rivers as both useful navigation corridors and functional ecosystems.

14.
Phys Rev Lett ; 132(15): 155101, 2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38682996

RESUMO

The sheared-flow-stabilized Z pinch concept has been studied extensively and is able to produce fusion-relevant plasma parameters along with neutron production over several microseconds. We present here elevated electron temperature results spatially and temporally coincident with the plasma neutron source. An optical Thomson scattering apparatus designed for the FuZE device measures temperatures in the range of 1-3 keV on the axis of the device, 20 cm downstream of the nose cone. The 17-fiber system measures the radial profiles of the electron temperature. Scanning the laser time with respect to the neutron pulse time over a series of discharges allows the reconstruction of the T_{e} temporal response, confirming that the electron temperature peaks simultaneously with the neutron output, as well as the pinch current and inductive voltage generated within the plasma. Comparison to spectroscopic ion temperature measurements suggests a plasma in thermal equilibrium. The elevated T_{e} confirms the presence of a plasma assembled on axis, and indicates limited radiative losses, demonstrating a basis for scaling this device toward net gain fusion conditions.

16.
Artigo em Inglês | MEDLINE | ID: mdl-38610116

RESUMO

Incarcerated gravid uterus (IGU) is a rare and serious obstetric complication. IGU is defined as the entrapment of the gravid uterus between the pubic symphysis and the sacral promontory. The incidence of IGU is 1 in 3000-10 000 cases. IGU is associated with significant obstetric complications, including preterm labor, intrauterine fetal death, growth restriction, renal failure, uterine ischemia/rupture and thrombosis. Here, we present the case of a primigravida with urinary retention at 14 weeks. On transabdominal ultrasound at 19+5/7 weeks the cervix was difficult to visualize, and the anterior uterine wall appeared thickened. The bladder was elongated superior to the uterus and the placenta was low-lying. Initially the patient was managed with intermittent self-catheterization, and subsequently indwelling catheterization was required from 22 weeks. At 30 weeks, the patient was transferred to a tertiary center and magnetic resonance imaging (MRI) was preformed due to challenging visualization of the cervix on ultrasound and the patient's continued symptoms of constipation and recurrent urinary infections. The MRI found a retroflexed gravid uterus, with vagina and endocervix displaced anteriorly and compressed by the gravid uterus. The findings were consistent with an incarcerated uterus. The patient subsequently had positive urinary cultures for Pseudomonas and rising creatinine. Given the obstructive uropathy and associated morbidity and mortality, a plan for elective pre-term delivery at 33+6/7 weeks was made. Delivery was by midline laparotomy, normal anatomy was restored after manual evacuation of the fundus from below the sacral promontory, and an uncomplicated lower segment transverse uterine cesarean section was performed.

17.
Molecules ; 29(7)2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38611860

RESUMO

Clean and renewable energy development is becoming frontier research for future energy resources, as renewable energy offers sustainable and environmentally friendly alternatives to non-renewable sources such as fossil fuels. Among various renewable energy sources, tremendous progress has been made in converting solar energy to electric energy by developing efficient organic photovoltaics. Organic photovoltaic materials comprising conjugated polymers (CP) with narrow optical energy gaps are promising candidates for developing sustainable sources due to their potentially lower manufacturing costs. Organic semiconductor materials with a high electron affinity are required for many optoelectronic applications. We have designed a series of organic semiconductors comprised of cyclopentadithiophene as a donor and thiadiazoloquinoxaline (TQ) as an acceptor, varying the π-conjugation and TQ-derivatives. We have employed density functional theory (DFT) and time-dependent DFT (TDDFT) to evaluate the designed CP's optoelectronic properties, such as optical energy gap, dipole moment, and absorption spectra. Our DFT/TDDFT result shows that the energy gap of CPs is lowered and redshifted in the absorption spectra if there is no insertion of conjugation units such as thiophene and selenophene between donor and acceptor. In addition, selenophene shows relatively better redshift behavior compared to thiophene. Our work also provides rational insight into designing donor/acceptor-based CPs for organic solar cells.

18.
Proc Natl Acad Sci U S A ; 121(13): e2305030121, 2024 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-38517975

RESUMO

During wildfires and fossil fuel combustion, biomass is converted to black carbon (BC) via incomplete combustion. BC enters the ocean by rivers and atmospheric deposition contributing to the marine dissolved organic carbon (DOC) pool. The fate of BC is considered to reside in the marine DOC pool, where the oldest BC 14C ages have been measured (>20,000 14C y), implying long-term storage. DOC is the largest exchangeable pool of organic carbon in the oceans, yet most DOC (>80%) remains molecularly uncharacterized. Here, we report 14C measurements on size-fractionated dissolved BC (DBC) obtained using benzene polycarboxylic acids as molecular tracers to constrain the sources and cycling of DBC and its contributions to refractory DOC (RDOC) in a site in the North Pacific Ocean. Our results reveal that the cycling of DBC is more dynamic and heterogeneous than previously believed though it does not comprise a single, uniformly "old" 14C age. Instead, both semilabile and refractory DBC components are distributed among size fractions of DOC. We report that DBC cycles within DOC as a component of RDOC, exhibiting turnover in the ocean on millennia timescales. DBC within the low-molecular-weight DOC pool is large, environmentally persistent and constitutes the size fraction that is responsible for long-term DBC storage. We speculate that sea surface processes, including bacterial remineralization (via the coupling of photooxidation of surface DBC and bacterial co-metabolism), sorption onto sinking particles and surface photochemical oxidation, modify DBC composition and turnover, ultimately controlling the fate of DBC and RDOC in the ocean.

19.
JCI Insight ; 9(8)2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38502186

RESUMO

BACKGROUNDSurvivors of pneumonia, including SARS-CoV-2 pneumonia, are at increased risk for cognitive dysfunction and dementia. In rodent models, cognitive dysfunction following pneumonia has been linked to the systemic release of lung-derived pro-inflammatory cytokines. Microglia are poised to respond to inflammatory signals from the circulation, and their dysfunction has been linked to cognitive impairment in murine models of dementia and in humans.METHODSWe measured levels of 55 cytokines and chemokines in bronchoalveolar lavage fluid and plasma from 341 patients with respiratory failure and 13 healthy controls, including 93 unvaccinated patients with COVID-19 and 203 patients with other causes of pneumonia. We used flow cytometry to sort neuroimmune cells from postmortem brain tissue from 5 patients who died from COVID-19 and 3 patients who died from other causes for single-cell RNA-sequencing.RESULTSMicroglia from patients with COVID-19 exhibited a transcriptomic signature suggestive of their activation by circulating pro-inflammatory cytokines. Peak levels of pro-inflammatory cytokines were similar in patients with pneumonia irrespective of etiology, but cumulative cytokine exposure was higher in patients with COVID-19. Treatment with corticosteroids reduced expression of COVID-19-specific cytokines.CONCLUSIONProlonged lung inflammation results in sustained elevations in circulating cytokines in patients with SARS-CoV-2 pneumonia compared with those with pneumonia secondary to other pathogens. Microglia from patients with COVID-19 exhibit transcriptional responses to inflammatory cytokines. These findings support data from rodent models causally linking systemic inflammation with cognitive dysfunction in pneumonia and support further investigation into the role of microglia in pneumonia-related cognitive dysfunction.FUNDINGSCRIPT U19AI135964, UL1TR001422, P01AG049665, P01HL154998, R01HL149883, R01LM013337, R01HL153122, R01HL147290, R01HL147575, R01HL158139, R01ES034350, R01ES027574, I01CX001777, U01TR003528, R21AG075423, T32AG020506, F31AG071225, T32HL076139.


Assuntos
COVID-19 , Citocinas , Microglia , SARS-CoV-2 , Humanos , COVID-19/imunologia , COVID-19/complicações , Microglia/metabolismo , Microglia/imunologia , Citocinas/metabolismo , Citocinas/sangue , Masculino , Feminino , Pessoa de Meia-Idade , Idoso , Pulmão/imunologia , Pulmão/patologia , Pulmão/virologia , Pulmão/metabolismo , Líquido da Lavagem Broncoalveolar/imunologia , Líquido da Lavagem Broncoalveolar/citologia , Disfunção Cognitiva/imunologia , Disfunção Cognitiva/metabolismo , Adulto , Encéfalo/metabolismo , Encéfalo/imunologia , Encéfalo/patologia
20.
mBio ; 15(4): e0045424, 2024 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-38497655

RESUMO

Salmonella serovars Typhi and Paratyphi cause a prolonged illness known as enteric fever, whereas other serovars cause acute gastroenteritis. Mechanisms responsible for the divergent clinical manifestations of nontyphoidal and enteric fever Salmonella infections have remained elusive. Here, we show that S. Typhi and S. Paratyphi A can persist within human macrophages, whereas S. Typhimurium rapidly induces apoptotic macrophage cell death that is dependent on Salmonella pathogenicity island 2 (SPI2). S. Typhi and S. Paratyphi A lack 12 specific SPI2 effectors with pro-apoptotic functions, including nine that target nuclear factor κB (NF-κB). Pharmacologic inhibition of NF-κB or heterologous expression of the SPI2 effectors GogA or GtgA restores apoptosis of S. Typhi-infected macrophages. In addition, the absence of the SPI2 effector SarA results in deficient signal transducer and activator of transcription 1 (STAT1) activation and interleukin 12 production, leading to impaired TH1 responses in macrophages and humanized mice. The absence of specific nontyphoidal SPI2 effectors may allow S. Typhi and S. Paratyphi A to cause chronic infections. IMPORTANCE: Salmonella enterica is a common cause of gastrointestinal infections worldwide. The serovars Salmonella Typhi and Salmonella Paratyphi A cause a distinctive systemic illness called enteric fever, whose pathogenesis is incompletely understood. Here, we show that enteric fever Salmonella serovars lack 12 specific virulence factors possessed by nontyphoidal Salmonella serovars, which allow the enteric fever serovars to persist within human macrophages. We propose that this fundamental difference in the interaction of Salmonella with human macrophages is responsible for the chronicity of typhoid and paratyphoid fever, suggesting that targeting the nuclear factor κB (NF-κB) complex responsible for macrophage survival could facilitate the clearance of persistent bacterial infections.


Assuntos
Salmonella typhi , Salmonella , Febre Tifoide , Humanos , Animais , Camundongos , Salmonella typhi/genética , Febre Tifoide/microbiologia , NF-kappa B , Macrófagos/microbiologia
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