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1.
J Anxiety Disord ; 104: 102876, 2024 May 05.
Artigo em Inglês | MEDLINE | ID: mdl-38723405

RESUMO

There are significant challenges to identifying which individuals require intervention following exposure to trauma, and a need for strategies to identify and provide individuals at risk for developing PTSD with timely interventions. The present study seeks to identify a minimal set of trauma-related symptoms, assessed during the weeks following traumatic exposure, that can accurately predict PTSD. Participants were 2185 adults (Mean age=36.4 years; 64% women; 50% Black) presenting for emergency care following traumatic exposure. Participants received a 'flash survey' with 6-8 varying symptoms (from a pool of 26 trauma symptoms) several times per week for eight weeks following the trauma exposure (each symptom assessed ∼6 times). Features (mean, sd, last, worst, peak-end scores) from the repeatedly assessed symptoms were included as candidate variables in a CART machine learning analysis to develop a pragmatic predictive algorithm. PTSD (PCL-5 ≥38) was present for 669 (31%) participants at the 8-week follow-up. A classification tree with three splits, based on mean scores of nervousness, rehashing, and fatigue, predicted PTSD with an Area Under the Curve of 0.836. Findings suggest feasibility for a 3-item assessment protocol, delivered once per week, following traumatic exposure to assess and potentially facilitate follow-up care for those at risk.

2.
Psychoneuroendocrinology ; 166: 107064, 2024 Apr 29.
Artigo em Inglês | MEDLINE | ID: mdl-38713929

RESUMO

Positive and negative affect have been shown to have implications for hormones like cortisol but how moment to moment changes in affect (i.e., affect variability) influence cortisol secretion is less well understood. Additionally, context characteristics such as mean affect and stress may influence the association between affect variability and cortisol output. In the current study, we examined affect, stress, and cortisol data from 113 participants (age range = 25-63, M = 35.63, SD = 11.34; 29% male; 42% White/Caucasian, 37% Asian or Pacific Islander, 13% Hispanic/Latino, 4% Black/African American, 1% Native American, Eskimo, or Aleut, 4% selected "other" for their race/ethnicity). Participants completed ecological momentary assessments assessing positive and negative affect and stress four times per day for five days and provided saliva samples at each time point. Saliva was assayed for cortisol, and area under the curve with respect to ground was computed. In a three-way interaction, both positive affect mean level and stress moderated the association between positive affect variability and cortisol (b = -1.55, t(100) = -3.29, SE = 0.47, p <.01, ß = -4.05). When breaking down this three-way interaction, in the context of low stress and high mean positive affect, variability was positively related to total cortisol output. In contrast, in the context of high stress and high mean positive affect, variability was negatively related to total cortisol output. While greater positive affect variability is generally worse for health-relevant outcomes (as prior research has shown and as we show here at low levels of stress), at high levels of stress, fluctuation in affect may be adaptive. For someone experiencing a high stress week, having fluctuations in positive affect may mean that they are adaptively changing to meet their environmental needs especially when they typically report high mean positive affect levels. There were no associations between negative affect variability and cortisol secretion nor did mean negative affect or stress play a moderating role for negative affect variability. This study provides evidence that positive affect variability's association with cortisol secretion throughout the day may vary based on stress and mean positive affect levels.

3.
Vet Parasitol ; 328: 110178, 2024 Mar 29.
Artigo em Inglês | MEDLINE | ID: mdl-38569277

RESUMO

The control of the sheep blowfly relies on the use of insecticides. There have been several reports of in vitro and in vivo resistance to the most widely-used flystrike control chemical, dicyclanil. A recent report also described in vitro resistance to imidacloprid in a strain collected from a single property over three consecutive seasons that also showed resistance to dicyclanil. The present study aimed to use in vitro assays to examine five field-collected blowfly strains to determine if this co-occurrence of resistance to dicyclanil and imidacloprid was present more widely in field strains and to also measure resistance patterns to the other currently-used flystrike control chemicals. Each of the strains showed significant levels of resistance to both dicyclanil and imidacloprid: resistance factors at the IC50 of 9.1-23.8 for dicyclanil, and 8.7-14.1 for imidacloprid. Resistance factors at the IC95 ranged from 16.5 to 53.7, and 14.6-24.3 for dicyclanil and imidacloprid, respectively. Resistance factors were up to 8.5 for cyromazine at the IC95. Resistance to dicyclanil and imidacloprid was suppressed by co-treatment with the cytochrome P450 inhibitor, aminobenzotriazole, implicating this enzyme system in the observed resistances. We discuss the implications of the co-occurrence of resistance to dicyclanil and imidacloprid on insecticide rotation strategies for blowfly control. We also discuss the roles of insecticide resistance, environmental factors (e.g. rainfall), operational factors (e.g. insecticide application technique) and other animal health issues (e.g. scouring / diarrhoea) that together will impact on the likelihood of flystrike occurring at an earlier time point than expected after insecticide application.

4.
bioRxiv ; 2024 Apr 20.
Artigo em Inglês | MEDLINE | ID: mdl-38659776

RESUMO

CRISPR-Cas9 is a useful tool for inserting precise genetic alterations through homology-directed repair (HDR), although current methods rely on provision of an exogenous repair template. Here, we tested the possibility of repairing heterozygous single nucleotide variants (SNVs) using the cell's own wild-type allele rather than an exogenous template. Using high-fidelity Cas9 to perform allele-specific CRISPR across multiple human leukemia cell lines as well as in primary hematopoietic cells from patients with leukemia, we find high levels of reversion to wild-type in the absence of exogenous template. Moreover, we demonstrate that bulk treatment to revert a truncating mutation in ASXL1 using CRISPR-mediated interallelic gene conversion (IGC) is sufficient to prolong survival in a human cell line-derived xenograft model (median survival 33 days vs 27.5 days; p = 0.0040). These results indicate that IGC can be applied to numerous types of leukemia and can meaningfully alter cellular phenotypes at scale. Because our method targets single-base mutations, rather than larger variants targeted by IGC in prior studies, it greatly expands the pool of risk-increasing genetic lesions which could potentially be targeted by IGC. This technique may reduce cost and complexity for experiments modeling phenotypic consequences of SNVs. The principles of SNV-specific IGC demonstrated in this proof-of-concept study could be applied to investigate the phenotypic effects of targeted clonal reduction of leukemogenic SNV driver mutations.

5.
Implement Sci Commun ; 5(1): 35, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38581011

RESUMO

BACKGROUND: This case study details the experience of the Proyecto Precancer in applying the Integrative Systems Praxis for Implementation Research (INSPIRE) methodology to guide the co-development, planning, implementation, adoption, and sustainment of new technologies and screening practices in a cervical cancer screening and management (CCSM) program in the Peruvian Amazon. We briefly describe the theoretical grounding of the INSPIRE framework, the phases of the INSPIRE process, the activities within each phase, and the RE-AIM outcomes used to evaluate program outcomes. METHODS: Proyecto Precancer iteratively engaged over 90 stakeholders in the Micro Red Iquitos Sur (MRIS) health network in the Amazonian region of Loreto, Perú, through the INSPIRE phases. INSPIRE is an integrative research methodology grounded in systems thinking, participatory action research, and implementation science frameworks such as the Consolidated Framework for Implementation Research. An interrupted time-series design with a mixed-methods RE-AIM (Reach, Effectiveness, Adoption, Implementation, and Maintenance) evaluation framework was used to examine the adoption of human papillomavirus (HPV) testing (including self-sampling), with direct treatment after visual inspection with portable thermal ablation, at the primary level. RESULTS: This approach, blending participatory action research, implementation science, and systems-thinking, led to rapid adoption and successful implementation of the new cervical cancer screening and management program within 6 months, using an HPV-based screen-and-treat strategy across 17 health facilities in one of the largest public health networks of the Peruvian Amazon. Monitoring and evaluation data revealed that, within 6 months, the MRIS had surpassed their monthly screening goals, tripling their original screening rate, with approximately 70% of HPV-positive women reaching a completion of care endpoint, compared with around 30% prior to the new CCSM strategy. CONCLUSIONS: Proyecto Precancer facilitated the adoption and sustainment of HPV testing with subsequent treatment of HPV-positive women (after visual inspection) using portable thermal ablation at the primary level. This was accompanied by the de-implementation of existing visual inspection-based screening strategies and colposcopy for routine precancer triage at the hospital level. This case study highlights how implementation science approaches were used to guide the sustained adoption of a new screen-and-treat strategy in the Peruvian Amazon, while facilitating de-implementation of older screening practices.

6.
Nicotine Tob Res ; 2024 Apr 08.
Artigo em Inglês | MEDLINE | ID: mdl-38584415

RESUMO

INTRODUCTION: Youth tobacco use remains a critical public health concern, and childhood use of candy tobacco imitation products (CTIP) is associated with cigarette use among youth. However, no research has examined the full extent of CTIP available for purchase in the United States. AIMS AND METHODS: We conducted a content analysis of CTIP available on English-language, US-based websites. We identified sites that marketed CTIP utilizing Google and candy retail websites, examining each product for product names, the tobacco product being replicated (eg, cigar and cigarette), manufacturer, candy flavor, images, product rating, pack color, and if the product had packaging that may appeal to youth. RESULTS: We found 66 CTIP available. The most popular CTIP were cigars, with 39 separate products (59%), followed by candy cigarettes-14 products (21%), candy pipes-8 products (12%), and chewing tobacco-5 products (8%). In the 52 products where packaging design was available, 39 (75%) had packaging that may appeal to youth. CONCLUSIONS: CTIP, many of which contain packaging appealing to youth, are widely available for purchase online across the United States. These findings could stimulate policy actions, such as removal of CTIP from popular retail websites, labeling of CTIP as potentially dangerous to youth, or age verification requirements for purchasing CTIP. IMPLICATIONS: CTIP continues to be sold on the internet despite research indicating candy cigarette product use by youth increases their likelihood of smoking. We conducted research to understand the extent to which CTIP are sold on the internet and whether these products are being marketed to youth. The results provide evidence that some of the largest retail companies in the world continue to sell CTIP, and the majority are sold in packaging that likely appeals to youth. The results suggest that further research into the market for these products is needed, and regulatory measures should be considered to prevent CTIP from leading to youth tobacco use.

7.
AJPM Focus ; 3(3): 100214, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38586824

RESUMO

Introduction: This is the first study to use the Common-Sense Model of Self-Regulation theory for oral health interventions in pediatric practices. The objective of this qualitative study was to assess adoption and implementation of theory-based multilevel oral health interventions, by clinicians (pediatricians and nurse practitioners) participating in a cluster randomized clinical trial, to create an oral health toolkit for widespread dissemination into pediatric practices. Methods: Semistructured interviews were conducted at the conclusion of the cluster randomized clinical trial with 21 clinicians from 9 practices participating in the intervention arm. Clinicians in this arm received Common-Sense Model of Self-Regulation theory-based education and resources to deliver oral health interventions to parents/caregivers and document in electronic medical record. Semistructured interview questions were based on the Diffusion of Innovations Theory, assessing adoption and implementation. The interviews were coded using NVivo (QRS International) software. Main themes were identified using a thematic analysis approach. Results: Five themes identified from the interviews included strengths of theory-based oral health training for clinicians, oral health resources to improve quality of care, considerations for efficient future implementation, financial considerations, and parent benefits and challenges. Clinicians found that the theory-based training and resources increased knowledge and confidence when addressing oral health with parents and required only ≤2 minutes in their workflow with no financial consequences. Clinicians reported an increase in oral health awareness among parents but suggested an overall need for more pediatric dentists. Conclusions: The Common-Sense Model of Self-Regulation theory-based education and resources were well received by clinicians and perceived to be beneficial without adverse impact on workflow or practice finances. An online toolkit is planned because these oral health interventions can be successfully implemented and delivered in medical settings.

8.
Vet Surg ; 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38591745

RESUMO

OBJECTIVE: To describe short-term outcomes and complications in dogs receiving meniscal suturing and concurrent tibial plateau leveling osteotomy (TPLO) with or without augmentation with an extracapsular suture. STUDY DESIGN: Retrospective case series. ANIMALS: Forty-three client-owned dogs submitted for cruciate ligament disease. METHODS: Dogs were included if meniscal suturing was performed during or after a TPLO procedure. Criteria included an unstable medial meniscus without evidence of a tear, a caudal vertical longitudinal tear with or without displacement, or if a bucket-handle tear was debrided and the remaining rim was unstable. Stifle stabilization was performed by either a standard TPLO or an augmented TPLO (TPLO + internal brace [IB]). Outcome measures included physical examination findings, radiographs, subjective gait examination, Liverpool Osteoarthritis in Dogs (LOAD) scores, and second-look arthroscopy. RESULTS: Forty-four meniscal repairs were performed in 43 dogs. Five types of meniscal tears were treated employing eight suture materials. Complications were documented in 15 cases (34%). The stabilization technique had a significant impact on the outcome (p = .049): TPLO + IB had a 93.3% success rate and the success rate was 71.4% in the TPLO-only group. CONCLUSION: Five types of meniscal pathology were addressed successfully in the study, indicating that currently accepted criteria for meniscal suturing in dogs may be overly conservative. The majority of complications were not related to the meniscal suturing itself and did not compromise the outcome. The stifle stabilization technique had an impact on outcome. CLINICAL SIGNIFICANCE: The authors found arthroscopic meniscal suturing to be practical and successful in this patient population. Postoperative stifle stability had an impact on successful treatment.

9.
Front Neurol ; 15: 1320727, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38601333

RESUMO

Background: The current study examined the sensitivity of two memory subtests and their corresponding learning slope metrics derived from the African Neuropsychology Battery (ANB) to detect amyloid pathology and APOEε4 status in adults from Kinshasa, the Democratic Republic of the Congo. Methods: 85 participants were classified for the presence of ß-amyloid pathology and based on allelic presence of APOEε4 using Simoa. All participants were screened using CSID and AQ, underwent verbal and visuospatial memory testing from ANB, and provided blood samples for plasma Aß42, Aß40, and APOE proteotype. Pearson correlation, linear and logistic regression were conducted to compare amyloid pathology and APOEε4 status with derived learning scores, including initial learning, raw learning score, learning over trials, and learning ratio. Results: Our sample included 35 amyloid positive and 44 amyloid negative individuals as well as 42 without and 39 with APOEε4. All ROC AUC ranges for the prediction of amyloid pathology based on learning scores were low, ranging between 0.56-0.70 (95% CI ranging from 0.44-0.82). The sensitivity of all the scores ranged between 54.3-88.6, with some learning metrics demonstrating good sensitivity. Regarding APOEε4 prediction, all AUC values ranged between 0.60-0.69, with all sensitivity measures ranging between 53.8-89.7. There were minimal differences in the AUC values across learning slope metrics, largely due to the lack of ceiling effects in this sample. Discussion: This study demonstrates that some ANB memory subtests and learning slope metrics can discriminate those that are normal from those with amyloid pathology and those with and without APOEε4, consistent with findings reported in Western populations.

10.
Atherosclerosis ; 392: 117525, 2024 Mar 27.
Artigo em Inglês | MEDLINE | ID: mdl-38598969

RESUMO

Homozygous familial hypercholesterolaemia is a life-threatening genetic condition, which causes extremely elevated LDL-C levels and atherosclerotic cardiovascular disease very early in life. It is vital to start effective lipid-lowering treatment from diagnosis onwards. Even with dietary and current multimodal pharmaceutical lipid-lowering therapies, LDL-C treatment goals cannot be achieved in many children. Lipoprotein apheresis is an extracorporeal lipid-lowering treatment, which is used for decades, lowering serum LDL-C levels by more than 70% directly after the treatment. Data on the use of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia mainly consists of case-reports and case-series, precluding strong evidence-based guidelines. We present a consensus statement on lipoprotein apheresis in children based on the current available evidence and opinions from experts in lipoprotein apheresis from over the world. It comprises practical statements regarding the indication, methods, treatment goals and follow-up of lipoprotein apheresis in children with homozygous familial hypercholesterolaemia and on the role of lipoprotein(a) and liver transplantation.

11.
MicroPubl Biol ; 20242024.
Artigo em Inglês | MEDLINE | ID: mdl-38681674

RESUMO

Optogenetics is a powerful tool used to manipulate physiological processes in animals through cell-specific expression of genetically modified channelrhodopsins. In Drosophila melanogaster, optogenetics is frequently used for temporal control of neuronal activation or silencing through light-dependent actuation of cation and anion channelrhodopsins, respectively. The high setup costs and complexity associated with commercially available optogenetic systems prevents many investigators from exploring the use of this technology. We developed a low-cost, customizable, and easy-to-make optogenetics chamber (OptoChamber) and verified its functionality in a robust cellular assay: activity-dependent remodeling of larval motor neurons in Drosophila embryos.

12.
Viruses ; 16(4)2024 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-38675936

RESUMO

Domestic dogs are currently recognized as being infected by 25 different canine papillomavirus (CPV) types classified into three genera. A short sequence from a novel CPV type was amplified, along with CPV1, from a papilloma (wart) from the mouth of a dog. The entire 7499 bp genome was amplified, and CPV26 contained putative coding regions that were predicted to produce four early proteins and two late ones. The ORF L1 showed less than 62% similarity for all previously sequenced CPV types but over 69% similarity to multiple Omegapapillomavirus types from a variety of Caniform species including the giant panda, Weddel seal, and polar bear. Phylogenetic analysis confirmed CPV26 clusters within the Omegapapillomavirus genus. Specific primers were used to investigate the presence of CPV26 DNA within a series of 37 canine proliferative lesions. CPV26 DNA was amplified from one lesion, a cutaneous papilloma that also contained CPV6. This is the first time a PV type within the Omegapapillomavirus genus has been detected in a non-domestic species and this provides evidence that the omegapapillomaviruses infected a common ancestor of, and then co-evolved with, the Caniform species. Whether CPV26 causes disease is uncertain, but the absence of an E7 protein may suggest low pathogenicity.


Assuntos
DNA Viral , Doenças do Cão , Genoma Viral , Papillomaviridae , Infecções por Papillomavirus , Filogenia , Animais , Cães , Infecções por Papillomavirus/virologia , Infecções por Papillomavirus/veterinária , Papillomaviridae/genética , Papillomaviridae/classificação , Doenças do Cão/virologia , DNA Viral/genética , Fases de Leitura Aberta , Análise de Sequência de DNA
13.
J Psychiatr Res ; 174: 319-325, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38685189

RESUMO

The biological mechanisms that explain how adverse early life events influence adult disease risk are poorly understood. One proposed mechanism is via the induction of accelerated biological aging, for which telomere length is considered a biomarker. We aimed to determine if maternal depression pre- and post-partum was associated with telomere length in children at 4 years of age (n = 4299). Mothers completed structured questionnaires assessing depression during pregnancy (Edinburgh Depression Scale), at 9 months (Edinburgh Depression Scale), and at 54 months postpartum (Patient Health Questionnaire 9). Regression methods were used to investigate the relationship between telomere length (DNA from saliva) and maternal depression score recorded at each stage. Significant covariates included in the final model were: maternal age at pregnancy; child sex; child ethnicity; gestational age group, and rurality group. Child telomere length was found to be longer if their mother had a higher depression score at both postpartum time points tested (9 months of age; coefficient 0.003, SE = 0.001, P = 0.01, 54 months of age; coefficient 0.003, SE = 0.002, P = 0.02). Although these findings seem paradoxical, increased telomere length may be an adaptive response to early life stressors. We propose several testable hypotheses for these results and to determine if the positive association between depression and telomere length is a developmental adaptation or an indirect consequence of environmental factors.

14.
Aging Ment Health ; : 1-7, 2024 Apr 23.
Artigo em Inglês | MEDLINE | ID: mdl-38651198

RESUMO

OBJECTIVES: The purpose of this study was to examine factors associated with engagement in meaningful activity among residents with dementia in assisted living. We hypothesized that greater functional independence, less pain, and lower behavioral and psychological symptom severity would be associated with higher engagement in meaningful activity after controlling for residents' age, gender, comorbidities, and cognition. Understanding factors associated with engagement in meaningful activity can help to inform strategies for optimizing engagement among residents with dementia in assisted living. METHOD: This descriptive study used baseline data from a randomized controlled trial, Meaningful Activity for Managing Behavioral Symptoms of Distress (MAC-4-BSD). Linear regression was used to examine factors associated with engagement in meaningful activity. RESULTS: A total of 71 residents from 5 assisted living settings were included in the sample. Most participants were female (n = 52, 73%), White (n = 62, 87%), and mean age was 85 years old (SD = 8.2). Controlling for age, gender, comorbidities, and cognition, pain was significantly associated with engagement in meaningful activity (b= -2.09, p < 0.05). There were no associations found between function and behavioral symptoms with engagement in meaningful activity. CONCLUSION: Findings from this study show that pain is a significant factor that is negatively associated with residents' engagement in meaningful activity. Ongoing research is needed to help improve pain management for residents with dementia in assisted living and support their engagement in meaningful activity.

15.
J Econ Entomol ; 2024 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-38634599

RESUMO

The number, timing, and fitness of colonizing parasitoids in fields of ephemeral crops often depend on factors external to the fields. We investigated cereal aphid parasitism in 23 winter wheat fields using sentinel plants infested with bird cherry-oat aphids, Rhopalosiphum padi (L.) (Hemiptera: Aphididae), and we investigated the effect of parasitoids on cereal aphid population growth using exclusion and parasitoid-accessible cages infested with bird cherry-oat aphids. Lysiphlebus testaceipes (Cresson) (Hymenoptera: Braconidae), Aphelinus nigritus (Howard) (Hymenoptera: Aphelinidae), and Diaeretiella rapae (McIntosh) (Hymenoptera: Braconidae), in decreasing order of abundance, parasitized R. padi on sentinel plants. The mean percent parasitism in parasitoid-accessible cages was 5.2% in autumn and 35.0% in spring. Aphid population intensity was greater in complete exclusion than in parasitoid-accessible cages. Measures of landscape composition and configuration were quantified, and aphid parasitism in autumn by L. testaceipes and A. nigritus was positively associated with % landcover by summer crops and patch density. Parasitism by both species was negatively associated with contagion and % woodlands. Parasitism during spring was positively associated with % grassland and fractal dimension and negatively associated with % canola. The number of braconid mummies per sentinel plant was positively correlated to the number of braconid mummies on wheat stems from parasitoid-accessible cages. Results indicate that cereal aphid mortality caused by parasitoids and their ability to exert effective biological control is related to landscape structure. Comparing this study to an earlier study in the same agroecosystem demonstrated temporal stability of the landscape influence on aphid parasitism by L. testaceipes in winter wheat.

16.
Pediatr Radiol ; 2024 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-38641735

RESUMO

BACKGROUND: The use of contrast-enhanced imaging has long been standard for magnetic resonance imaging (MRI) assessments of synovitis in juvenile idiopathic arthritis (JIA). However, advancements in MRI technology have allowed for reliable identification of synovium without contrast. OBJECTIVE: To assess the equivalence of unenhanced MRI with contrast-enhanced MRI in evaluating synovial thickness. MATERIALS AND METHODS: This is an institutional review board approved, retrospective study performed in a tertiary children's hospital. Pediatric JIA patients under 21 years old were included who underwent knee MRI scans (1.5 T or 3 T) without and with contrast between January 2012 and January 2022. Two radiologists independently measured synovial thickness at 6 knee sites on contrast-enhanced and unenhanced sequences. Numerical measurements and ordinal scores based on juvenile idiopathic arthritis magnetic resonance imaging scoring (JAMRIS) system were recorded, and tests of equivalence were conducted, as well as between-reader and within-reader reliability by concordance correlation coefficient (CCC). All tests were considered significant at the 5% level. RESULTS: A total of 38 studies from 35 patients (25 females, median age 14 years; interquartile range 7 to 15.7) were included. Equivalence was demonstrated at each of the 6 sites for both continuous measurements (P-values < 0.05) and ordinal scores (P-values < 0.05) based on the average over readers. Within-reader reliability was moderate to high (CCC 0.50-0.89), except for the cruciate ligaments site. Averaged over the 6 sites, reliability between readers was low for unenhanced (CCC 0.47, with 95% CI: [0.41, 0.53]) and moderate for contrast-enhanced (CCC 0.64, with 95% CI: [0.59, 0.69]) sequences. CONCLUSION: Unenhanced knee MRI is equivalent to contrast-enhanced MRI in assessment of synovial thickness using conventional MRI sequences. Contrast material helped improve inter-reader reliability.

17.
J Am Chem Soc ; 146(15): 10679-10686, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38579336

RESUMO

Nitrenium ions are important reactive intermediates participating in the synthetic chemistry and biological processes. Little is known about triplet phenyl nitrenium ions regarding their reactivity, lifetimes, spectroscopic features, and electronic configurations, and no ground state triplet nitrenium ion has been directly detected. In this work, m-pyrrolidinyl-phenyl hydrazine hydrochloride (1) is synthesized as the photoprecursor to photochemically generate the corresponding m-pyrrolidinyl-phenyl nitrenium ion (2), which is computed to adopt a π, π* triplet ground state. A combination of femtosecond (fs) and nanosecond (ns) transient absorption (TA) spectroscopy, cryogenic continuous-wave electronic paramagnetic resonance (CW-EPR) spectroscopy, computational analysis, and photoproduct studies was performed to elucidate the photolysis pathway of 1 and offers the first direct experimental detection of a ground state triplet phenyl nitrenium ion. Upon photoexcitation, 1 forms S1, where bond heterolysis occurs and the NH3 leaving group is extruded in 1.8 ps, generating a vibrationally hot, spin-conserving closed-shell singlet phenyl nitrenium ion (12) that undergoes vibrational cooling in 19 ps. Subsequent intersystem crossing takes place in 0.5 ns, yielding the ground state triplet phenyl nitrenium ion (32), with a lifetime of 0.8 µs. Unlike electrophilic singlet phenyl nitrenium ions, which react rapidly with nucleophiles, this triplet phenyl nitrenium reacts through sequential H atom abstractions, resulting in the eventual formation of the reduced m-pyrrolidinyl-aniline as the predominant stable photoproduct. Supporting the triplet ground state, continuous irradiation of 1 in a glassy matrix at 80 K in an EPR spectrometer forms a paramagnetic triplet species, consistent with a triplet nitrenium ion.

18.
J Am Heart Assoc ; 13(8): e033323, 2024 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-38591328

RESUMO

BACKGROUND: Food insecurity, a social and economic condition of limited availability of healthy food, is a risk factor for adverse cardiovascular health outcomes among adults; few studies have been conducted in adolescents. This study explores the association between food insecurity and cardiovascular health risk factors among a nationally representative sample of US adolescents, adopting the American Heart Association's Life's Essential 8 metric. METHODS AND RESULTS: We analyzed data from 2534 adolescents aged 12 to 19 years from the 2013 to 2018 National Health and Nutrition Examination Surveys. In the sample, 24.8% of adolescents lived in food-insecure households. After multivariable adjustment, food insecurity was associated with a 3.23-unit lower total Life's Essential 8 score (95% CI, -6.32, -0.15) and lower scores on diet quality (ß=-5.39 [95% CI, -8.91, -1.87]) and nicotine exposure (ß=-4.85 [95% CI, -9.24, -0.45]). Regarding diet, food insecurity was associated with 5% lower Healthy Eating Index-2015 scores [95% CI, -7%, -2%], particularly lower intakes of whole grains and seafood/plant proteins and marginally higher intake of added sugar. Regarding nicotine exposure, food insecurity was associated with ever use of a tobacco product among m (odds ratio, 1.74 [95% CI, 1.20-2.53]). Compared with their food-secure counterparts, food-insecure male (odds ratio, 1.98 [95% CI, 1.07-3.65]) and female (odds ratio, 3.22 [95% CI, 1.60-6.45]) adolescents had higher odds of living with a current indoor smoker. CONCLUSIONS: In this nationally representative sample of adolescents, food insecurity was associated with multiple indicators of cardiovascular health risk. These findings underscore the need for public health interventions and policies to reduce food insecurity and improve cardioprotective behaviors during adolescence, with particular efforts targeting diet quality and nicotine exposure.


Assuntos
Abastecimento de Alimentos , Nicotina , Adulto , Humanos , Adolescente , Estados Unidos/epidemiologia , Dieta , Fatores de Risco , Inquéritos Nutricionais , Insegurança Alimentar
19.
J Biol Chem ; 300(5): 107275, 2024 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-38588814

RESUMO

DNA replication in Escherichia coli starts with loading of the replicative helicase, DnaB, onto DNA. This reaction requires the DnaC loader protein, which forms a 6:6 complex with DnaB and opens a channel in the DnaB hexamer through which single-stranded DNA is thought to pass. During replication, replisomes frequently encounter DNA damage and nucleoprotein complexes that can lead to replication fork collapse. Such events require DnaB re-loading onto DNA to allow replication to continue. Replication restart proteins mediate this process by recruiting DnaB6/DnaC6 to abandoned DNA replication forks. Several dnaC mutations that bypass the requirement for replication restart proteins or that block replication restart have been identified in E. coli. To better understand how these DnaC variants function, we have purified and characterized the protein products of several such alleles. Unlike wild-type DnaC, three of the variants (DnaC 809, DnaC 809,820, and DnaC 811) can load DnaB onto replication forks bound by single-stranded DNA-binding protein. DnaC 809 can also load DnaB onto double-stranded DNA. These results suggest that structural changes in the variant DnaB6/DnaC6 complexes expand the range of DNA substrates that can be used for DnaB loading, obviating the need for the existing replication restart pathways. The protein product of dnaC1331, which phenocopies deletion of the priB replication restart gene, blocks loading through the major restart pathway in vitro. Overall, the results of our study highlight the utility of bacterial DnaC variants as tools for probing the regulatory mechanisms that govern replicative helicase loading.

20.
Artigo em Inglês | MEDLINE | ID: mdl-38522649

RESUMO

BACKGROUND: Females are more likely to develop posttraumatic stress disorder (PTSD) than males. Impaired inhibition has been identified as mechanism for PTSD development, but studies on the potential sex differences of this neurobiological mechanism and how it relates to PTSD severity and progression are sparse. Here we examined sex differences in neural activation during response inhibition and PTSD following recent trauma. METHODS: Participants (N= 205, 138 female sex assigned at birth) were recruited from emergency departments within 72 hours of a traumatic event. PTSD symptoms were assessed 2-weeks and 6-months post-trauma. A Go/NoGo task was performed 2-weeks post-trauma in a 3T MRI scanner to measure neural activity during response inhibition in the ventromedial prefrontal cortex (vmPFC), right inferior frontal gyrus (rIFG), and the bilateral hippocampus. General Linear models were used to examine the interaction effect of sex on the relationship between our regions of interest (ROIs) and the whole brain, and PTSD symptoms at 6-months, and symptom progression between 2-weeks and 6-months. RESULTS: Lower response-inhibition-related vmPFC activation 2-weeks post-trauma predicted more PTSD symptoms at 6-months in females but not in males, while greater response-inhibition-related rIFG activation predicted lower PTSD symptom progression in males but not females. Whole brain interaction effects were observed in the medial temporal gyrus and left precentral gyrus. CONCLUSIONS: There are sex differences in the relationship between inhibition-related brain activation and PTSD symptom severity and progression. These findings suggest that sex differences should be assessed in future PTSD studies and reveal potential targets for sex-specific interventions.

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