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1.
Artigo em Inglês | MEDLINE | ID: mdl-39073296

RESUMO

BACKGROUND: Alcohol is commonly consumed by adolescents in a binge-like pattern, which can lead to long-lasting cognitive deficits, including reduced behavioral flexibility. We and others have determined that adolescent intermittent ethanol (AIE) exposure leads to increased number of perineuronal net (PNN) numbers in brain regions that are important for behavioral flexibility. However, whether altered neurochemistry stemming from AIE exposure plays a significant role in reduced behavioral flexibility is unknown. METHODS: We measured the number and size of parvalbumin expressing (PV+) interneurons and associated PNNs within the orbitofrontal cortex (OFC), prelimbic cortex (PrL), infralimbic cortex (IL), and anterior insular cortex (AIC) of female and male rats following AIE or control exposure and subsequent training on an attentional set-shift task (ASST). We then ran analyses to determine whether AIE-induced changes in PV and PNN measures statistically mediated the AIE-induced behavioral deficit in reversal learning. RESULTS: We demonstrate that AIE exposure impaired behavioral flexibility on reversal two of the ASST (i.e., recalling the initial learned associations), and led to smaller PV+ cells and increased PNN numbers in the AIC. Interestingly, PNN size and number were not altered in the PrL or IL following AIE exposure, in contrast to prior reports. Mediation analyses suggest that AIE alters behavioral flexibility, at least in part through changes in PV and PNN fluorescent measures in the AIC. CONCLUSIONS: This study reveals a significant link between AIE exposure, neural alterations, and diminished behavioral flexibility in rats, and highlights a potential novel mechanism comprising changes in PV and PNN measures within the AIC. Future studies should explore the impact of PNN degradation within the AIC on behavioral flexibility.

2.
Pharmaceutics ; 16(7)2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-39065600

RESUMO

Extracellular vesicles (EVs) are of growing interest in the context of screening for highly informative cancer markers. We have previously shown that uterine aspirate EVs (UA EVs) are a promising source of ovarian cancer (OC) diagnostic markers. In this study, we first conducted an integrative analysis of EV-miRNA profiles from UA, malignant ascitic fluid (AF), and a conditioned medium of cultured ascites cells (ACs). Using three software packages, we identified 79 differentially expressed miRNAs (DE-miRNAs) in UA EVs from OC patients and healthy individuals. To narrow down this panel and select miRNAs most involved in OC pathogenesis, we aligned these molecules with the DE-miRNA sets obtained by comparing the EV-miRNA profiles from OC-related biofluids with the same control. We found that 76% of the DE-miRNAs from the identified panel are similarly altered (differentially co-expressed) in AF EVs, as are 58% in AC EVs. Interestingly, the set of miRNAs differentially co-expressed in AF and AC EVs strongly overlaps (40 out of 44 miRNAs). Finally, the application of more rigorous criteria for DE assessment, combined with the selection of miRNAs that are differentially co-expressed in all biofluids, resulted in the identification of a panel of 29 miRNAs for ovarian cancer screening.

3.
JAMA Oncol ; 2024 Jul 03.
Artigo em Inglês | MEDLINE | ID: mdl-38959011

RESUMO

Importance: Pancreatic ductal adenocarcinoma (PDAC) is a deadly disease with increasing incidence. The majority of PDACs are incurable at presentation, but population-based screening is not recommended. Surveillance of high-risk individuals for PDAC may lead to early detection, but the survival benefit is unproven. Objective: To compare the survival of patients with surveillance-detected PDAC with US national data. Design, Setting, and Participants: This comparative cohort study was conducted in multiple US academic medical centers participating in the Cancer of the Pancreas Screening program, which screens high-risk individuals with a familial or genetic predisposition for PDAC. The comparison cohort comprised patients with PDAC matched for age, sex, and year of diagnosis from the Surveillance, Epidemiology, and End Results (SEER) program. The Cancer of the Pancreas Screening program originated in 1998, and data collection was done through 2021. The data analysis was performed from April 29, 2022, through April 10, 2023. Exposures: Endoscopic ultrasonography or magnetic resonance imaging performed annually and standard-of-care surgical and/or oncologic treatment. Main Outcomes and Measures: Stage of PDAC at diagnosis, overall survival (OS), and PDAC mortality were compared using descriptive statistics and conditional logistic regression, Cox proportional hazards regression, and competing risk regression models. Sensitivity analyses and adjustment for lead-time bias were also conducted. Results: A total of 26 high-risk individuals (mean [SD] age at diagnosis, 65.8 [9.5] years; 15 female [57.7%]) with PDAC were compared with 1504 SEER control patients with PDAC (mean [SD] age at diagnosis, 66.8 [7.9] years; 771 female [51.3%]). The median primary tumor diameter of the 26 high-risk individuals was smaller than in the control patients (2.5 [range, 0.6-5.0] vs 3.6 [range, 0.2-8.0] cm, respectively; P < .001). The high-risk individuals were more likely to be diagnosed with a lower stage (stage I, 10 [38.5%]; stage II, 8 [30.8%]) than matched control patients (stage I, 155 [10.3%]; stage II, 377 [25.1%]; P < .001). The PDAC mortality rate at 5 years was lower for high-risk individuals than control patients (43% vs 86%; hazard ratio, 3.58; 95% CI, 2.01-6.39; P < .001), and high-risk individuals lived longer than matched control patients (median OS, 61.7 [range, 1.9-147.3] vs 8.0 [range, 1.0-131.0] months; 5-year OS rate, 50% [95% CI, 32%-80%] vs 9% [95% CI, 7%-11%]). Conclusions and Relevance: These findings suggest that surveillance of high-risk individuals may lead to detection of smaller, lower-stage PDACs and improved survival.

4.
Front Psychiatry ; 15: 1380620, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38974918

RESUMO

Background: Research on depression showed that dysregulations in tryptophan (TRP), kynurenine (KYN), and its KYN pathway metabolites are key aspects in the development and maintenance of depressive symptoms. In our previous reports, we described sex-specific changes in TRP breakdown as well as changes in KYN and KYN/TRP in association with treatment response and inflammatory and metabolic parameters. However, results of treatment effects on KYN pathway metabolites as well as how pathway changes are related to treatment response remain sparse. Objective: We investigated potential changes of KYN and KYN pathway metabolites in association with therapeutic response of individuals with depression during a six-week multimodal psychiatric rehabilitation program. Methods: 87 participants were divided into treatment responders and non-responders (48 responders, 39 non-responders; 38 male, 49 female; M age = 51.09; SD age = 7.70) using scores of psychological questionnaires. KYN pathway metabolites serum concentrations as well as their ratios were collected using high performance liquid chromatography. Changes over time (time of admission (t1) vs. time of discharge (t2)) were calculated using repeated measure analyses of (co)variance. Results: Non-responders exhibited higher levels of 3-Hydroxyanthralinic acid (3-HAA), nicotinic acid (NA), and 3-HAA/KYN, independently of measurement time. NA levels decreased, while 3-HAA levels increased over time in both groups, independently of treatment response. 3-HK/KYN levels decreased, while KYN levels increased in non-responders, but not in responders over time. Discussion: The results indicate that some compounds of the KYN pathway metabolites can be altered through multimodal long-term interventions in association with treatment response. Especially the pathway degrading KYN further down to 3-HAA and 3-HK/KYN might be decisive for treatment response in depression.

5.
Eye Contact Lens ; 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38978195

RESUMO

OBJECTIVE: To evaluate the relationship between social determinants of health and the likelihood of receiving a premium intraocular lens (IOL) at the time of cataract surgery. METHODS: Retrospective chart review of a single-center, academic ophthalmology practice over a one-year period, with a primary outcome measure of placement of either a premium or standard IOL. We used logistic regression to calculate the odds of receiving a premium IOL, stratifying patients based on self-identified race/ethnicity, age, sex, insurance type (private insurance vs. Medicare or Medicaid), estimated household income (based on median household income for zip code), and presence of ocular pathology. RESULTS: Compared with self-identified White patients, Black patients were least likely to receive premium IOLs (OR=0.220, 95% CI 0.137-0.340, P<0.001), followed by Hispanic patients (OR=0.308, 95% CI 0.104-0.730) and Asian patients (OR=0.479, 95% CI 0.302-0.734). Patients with Medicare or Medicaid insurance were also less likely to receive premium IOLs (OR 0.522, 95% CI 0.336-0.784). CONCLUSIONS: White patients in our practice were more likely to receive premium IOLs than non-White patients, even when controlling for age, sex, insurance type, estimated median household income, and presence of ocular comorbidities. The underlying reason for this disparity should be explored further.

6.
Clin Transplant ; 38(7): e15401, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39023081

RESUMO

BACKGROUND: The use of glucagon-like-peptide 1 receptor agonists (GLP1-RA) has dramatically increased over the past 5 years for diabetes mellitus type 2 (T2DM) and obesity. These comorbidities are prevalent in adult heart transplant (HT) recipients. However, there are limited data evaluating the efficacy of this drug class in this population. The aim of the current study was to describe cardiometabolic changes in HT recipients prescribed GLP1-RA at a large-volume transplant center. METHODS: We retrospectively reviewed all adult HT recipients who received GLP1-RA after HT for a minimum of 1-month. Cardiometabolic parameters including body mass index (BMI), lipid panel, hemoglobin A1C, estimated glomerular filtration rate (eGFR), and NT-proBNP were compared prior to initiation of the drug and at most recent follow-up. We also evaluated for significant dose adjustments to immunosuppression after drug initiation and adverse effects leading to drug discontinuation. RESULTS: Seventy-four patients were included (28% female, 53% White, 20% Hispanic) and followed for a median of 383 days [IQR 209, 613] on a GLP1-RA. The majority of patients (n = 56, 76%) were prescribed semaglutide. The most common indication for prescription was T2DM alone (n = 33, 45%), followed by combined T2DM and obesity (n = 26, 35%). At most recent follow-up, mean BMI decreased from 33.3 to 31.5 kg/m2 (p < 0.0001), HbA1C from 7.3% to 6.7% (p = 0.005), LDL from 78.6 to 70.3 mg/dL (p = 0.018) and basal insulin daily dose from 32.6 to 24.8 units (p = 0.0002). CONCLUSION: HT recipients prescribed GLP1-RA therapy showed improved glycemic control, weight loss, and cholesterol levels during the study follow-up period. GLP1-RA were well tolerated and were rarely associated with changes in immunosuppression dosing.


Assuntos
Receptor do Peptídeo Semelhante ao Glucagon 1 , Transplante de Coração , Humanos , Feminino , Masculino , Estudos Retrospectivos , Pessoa de Meia-Idade , Receptor do Peptídeo Semelhante ao Glucagon 1/agonistas , Transplante de Coração/efeitos adversos , Seguimentos , Prognóstico , Diabetes Mellitus Tipo 2/tratamento farmacológico , Taxa de Filtração Glomerular , Hipoglicemiantes/uso terapêutico , Testes de Função Renal , Adulto , Complicações Pós-Operatórias/tratamento farmacológico , Rejeição de Enxerto/etiologia , Rejeição de Enxerto/prevenção & controle , Rejeição de Enxerto/tratamento farmacológico , Agonistas do Receptor do Peptídeo 1 Semelhante ao Glucagon
7.
J Headache Pain ; 25(1): 113, 2024 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-39009958

RESUMO

BACKGROUND: Neurogenic meningeal inflammation is regarded as a key driver of migraine headache. Multiple evidence show importance of inflammatory processes in the dura mater for pain generation but contribution of the leptomeninges is less clear. We assessed effects of cortical spreading depolarization (CSD), the pathophysiological mechanism of migraine aura, on expression of inflammatory mediators in the leptomeninges. METHODS: A single CSD event was produced by a focal unilateral microdamage of the cortex in freely behaving rats. Three hours later intact cortical leptomeninges and parenchyma of ipsi-lesional (invaded by CSD) and sham-treated contra-lesional (unaffected by CSD) hemispheres were collected and mRNA levels of genes associated with inflammation (Il1b, Tnf, Ccl2; Cx3cl1, Zc3h12a) and endocannabinoid CB2 receptors (Cnr2) were measured using qPCR. RESULTS: Three hours after a single unilateral CSD, most inflammatory factors changed their expression levels in the leptomeninges, mainly on the side of CSD. The meninges overlying affected cortex increased mRNA expression of all proinflammatory cytokines (Il1b, Tnf, Ccl2) and anti-inflammatory factors Zc3h12a and Cx3cl1. Upregulation of proinflammatory cytokines was found in both meninges and parenchyma while anti-inflammatory markers increased only meningeal expression. CONCLUSION: A single CSD is sufficient to produce pronounced leptomeningeal inflammation that lasts for at least three hours and involves mostly meninges overlying the cortex affected by CSD. The prolonged post-CSD inflammation of the leptomeninges can contribute to mechanisms of headache generation following aura phase of migraine attack.


Assuntos
Depressão Alastrante da Atividade Elétrica Cortical , Meninges , Animais , Depressão Alastrante da Atividade Elétrica Cortical/fisiologia , Ratos , Masculino , Meninges/fisiopatologia , Inflamação/fisiopatologia , Córtex Cerebral/metabolismo , Córtex Cerebral/fisiopatologia , Modelos Animais de Doenças , Ratos Wistar , Quimiocina CX3CL1/metabolismo , Quimiocina CX3CL1/genética
8.
Polymers (Basel) ; 16(13)2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-39000644

RESUMO

Cerium oxide nanoparticles (CeONPs), as part of tissue regeneration matrices, can protect cells from reactive oxygen species and oxidative stress. In addition, they can influence the properties of the scaffold, including its electrospinnability and mechanical strength. In this work, we prepared electrospun fiber mats from a chitosan and polyethylene oxide blend (CS-PEO) with the addition of ceria nanoparticles (CS-PEO-CeONP). The addition of CeONPs resulted in a smaller fiber diameter and higher swelling compared to CS-PEO fiber mats. CeONP-modified fiber mats also had a higher Young's modulus due to the reinforcing effect of the nanoparticles. Both mats had comparable adhesion and cytocompatibility to mesenchymal stem cells, which had a more rounded morphology on CS-PEO-CeONP compared to elongated cells on the CS-PEO mats. Biocompatibility in an in vivo rat model showed no acute toxicity, no septic or allergic inflammation, and no rough scar tissue formation. The degradation of both mats passed the stage of matrix swelling. CS-PEO-CeONP showed significantly slower biodegradation, with most of the matrix remaining in the tissue after 90 days. The reactive inflammation was aseptic in nature with the involvement of multinucleated foreign-body type giant cells and was significantly reduced by day 90. CeONPs induced the formation of the implant's connective tissue capsule. Thus, the introduction of CeONPs influenced the physicochemical properties and biological activity of CS-PEO nanofiber mats.

9.
Adv Neonatal Care ; 24(4): 354-363, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38976901

RESUMO

BACKGROUND: Despite available training programs for neonatal advanced practice providers (Neo APP), including neonatal nurse practitioners and physician assistants, it is difficult to meet the demand for these providers. There are no publications regarding training models with greater than 1 Neo APP learner per mentor. PURPOSE: To create and measure outcomes of a 12-month program to educate Neo APP "Super-Mentors" able to train 2 Neo APP learners simultaneously. METHODS: Super-Mentors were selected and attended monthly classes to learn mentorship concepts and receive support. Learners received didactic content and support through a Fellowship program. Quantitative data regarding recruitment and retention, as well as Misener Nurse Practitioner Job Satisfaction Scale (MNPJSS) results were compared pre- and postprogram. Qualitative satisfaction measures via survey from 21 stakeholders were analyzed through a phenomenological approach. RESULTS: Six Super-Mentors trained 14 Neo APPs, as compared to 7 in the previous year. One Neo APP left after training. Summative preprogram MNPJSS scores were better (5.1 ± 0.37) than postprogram (4.7 ± 0.47) ( P < .001). The most important preprogram subscale item was "vacation" versus "quality of assistive personnel" postprogram. Both pre- and postprogram scores reflected positive job satisfaction so differences may not be clinically significant. Qualitative program benefits included faster and increased onboarding, stronger relationships, and dedicated time. Challenges included role clarity among other stakeholders, learning culture, and spacial/technological logistics. IMPLICATIONS FOR PRACTICE: Super-Mentors can train twice the number of Neo APP learners, with optimal preparation and support of all stakeholders, adequate space, and appropriate technology.


Assuntos
Mentores , Profissionais de Enfermagem , Humanos , Mentores/psicologia , Profissionais de Enfermagem/educação , Assistentes Médicos/educação , Satisfação no Emprego , Enfermagem Neonatal/educação , Enfermagem Neonatal/métodos , Prática Avançada de Enfermagem/educação , Prática Avançada de Enfermagem/métodos , Feminino , Recém-Nascido , Masculino
10.
PLoS Pathog ; 20(7): e1012338, 2024 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-39008527

RESUMO

Recently published near full-length KSHV genomes from a Cameroon Kaposi sarcoma case-control study showed strong evidence of viral recombination and mixed infections, but no sequence variations associated with disease. Using the same methodology, an additional 102 KSHV genomes from 76 individuals with KSHV-associated diseases have been sequenced. Diagnoses comprise all KSHV-associated diseases (KAD): Kaposi sarcoma (KS), primary effusion lymphoma (PEL), KSHV-associated large cell lymphoma (KSHV-LCL), a type of multicentric Castleman disease (KSHV-MCD), and KSHV inflammatory cytokine syndrome (KICS). Participants originated from 22 different countries, providing the opportunity to obtain new near full-length sequences of a wide diversity of KSHV genomes. These include near full-length sequence of genomes with KSHV K1 subtypes A, B, C, and F as well as subtype E, for which no full sequence was previously available. High levels of recombination were observed. Fourteen individuals (18%) showed evidence of infection with multiple KSHV variants (from two to four unique genomes). Twenty-six comparisons of sequences, obtained from various sampling sites including PBMC, tissue biopsies, oral fluids, and effusions in the same participants, identified near complete genome conservation between different biological compartments. Polymorphisms were identified in coding and non-coding regions, including indels in the K3 and K15 genes and sequence inversions here reported for the first time. One such polymorphism in KSHV ORF46, specific to the KSHV K1 subtype E2, encoded a mutation in the leucine loop extension of the uracil DNA glycosylase that results in alteration of biochemical functions of this protein. This confirms that KSHV sequence variations can have functional consequences warranting further investigation. This study represents the largest and most diverse analysis of KSHV genome sequences to date among individuals with KAD and provides important new information on global KSHV genomics.


Assuntos
Genoma Viral , Herpesvirus Humano 8 , Sarcoma de Kaposi , Humanos , Herpesvirus Humano 8/genética , Sarcoma de Kaposi/virologia , Sarcoma de Kaposi/genética , Masculino , Feminino , Pessoa de Meia-Idade , Adulto , Polimorfismo Genético , Idoso , Infecções por Herpesviridae/genética , Infecções por Herpesviridae/virologia , Etnicidade/genética , Hiperplasia do Linfonodo Gigante/virologia , Hiperplasia do Linfonodo Gigante/genética , Filogenia
11.
Genesis ; 62(4): e23612, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-39054872

RESUMO

The SRY HMG box transcription factor Sox21 plays multiple critical roles in neurogenesis, with its function dependent on concentration and developmental stage. In the allotetraploid Xenopus laevis, there are two homeologs of sox21, namely sox21.S and sox21.L. Previous studies focused on Sox21.S, but its amino acid sequence is divergent, lacking conserved poly-A stretches and bearing more similarity with ancestral homologs. In contrast, Sox21.L shares higher sequence similarity with mouse and chick Sox21. To determine if Sox21.S and Sox21.L have distinct functions, we conducted gain and loss-of-function studies in Xenopus embryos. Our studies revealed that Sox21.S and Sox21.L are functionally redundant, but Sox21.L is more effective at driving changes than Sox21.S. These results also support our earlier findings in ectodermal explants, demonstrating that Sox21 function is dose-dependent. While Sox21 is necessary for primary neuron formation, high levels prevent their formation. Strikingly, these proteins autoregulate, with high levels of Sox21.L reducing sox21.S and sox21.L mRNA levels, and decreased Sox21.S promoting increased expression of sox21.L. Our findings shed light on the intricate concentration-dependent roles of Sox21 homeologs in Xenopus neurogenesis.


Assuntos
Regulação da Expressão Gênica no Desenvolvimento , Neurogênese , Proteínas de Xenopus , Xenopus laevis , Animais , Neurogênese/genética , Xenopus laevis/genética , Proteínas de Xenopus/genética , Proteínas de Xenopus/metabolismo , Neurônios/metabolismo , Fatores de Transcrição SOXB2/genética , Fatores de Transcrição SOXB2/metabolismo
12.
AIDS Behav ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39046612

RESUMO

Research regarding HIV, substance use disorders (SUD), and SARS-CoV-2 infections after COVID-19 vaccination is limited. In the Veterans Aging Cohort Study (VACS)-HIV cohort, we followed vaccinated persons with HIV (PWH) and without HIV (PWoH) from 12/2020 to 3/2022 and linked SARS-CoV-2 test results for laboratory-confirmed breakthrough infection through 9/2022. We examined associations of substance use (alcohol use disorder [AUD], other SUD, smoking status) and HIV status and severity with breakthrough infections, using Cox proportional hazards regression hazard ratios (HR). To test for potential interactions between substance use and HIV, we fit survival models with a multiplicative interaction term. Among 24,253 PWH and 53,661 PWoH, 8.0% of PWH and 7.1% of PWoH experienced COVID-19 breakthrough. AUD (HR 1.42, 95% CI 1.32, 1.52) and other SUD (HR 1.49, 95% CI 1.39, 1.59) were associated with increased risk of breakthrough, and this was similar by HIV status (p-interaction > 0.09). Smoking was not associated with breakthrough. Compared to PWoH, PWH at all HIV severity levels had increased risk of breakthrough ranging from 9% for PWH with CD4 count ≥ 500 cells/µl (HR 1.09, 95% CI 1.02, 1.17) to 59% for PWH with CD4 count < 200 (HR 1.59, 95% CI 1.31, 1.92). Patients with AUD (HR 1.42, 95% CI 1.33, 1.52) and other SUD (HR 1.48, 95% CI 1.38, 1.59) had increased COVID-19 breakthrough risk, regardless of HIV status. HIV was associated with breakthrough; risk was greatest among PWH with lower CD4 count. In addition to inhibiting HIV treatment adherence and increasing HIV progression, AUD and other SUD may increase COVID-19 breakthrough risk.

13.
Sci Adv ; 10(27): eadn9423, 2024 Jul 05.
Artigo em Inglês | MEDLINE | ID: mdl-38968349

RESUMO

DNA origami nanostructures (DOs) are promising tools for applications including drug delivery, biosensing, detecting biomolecules, and probing chromatin substructures. Targeting these nanodevices to mammalian cell nuclei could provide impactful approaches for probing, visualizing, and controlling biomolecular processes within live cells. We present an approach to deliver DOs into live-cell nuclei. We show that these DOs do not undergo detectable structural degradation in cell culture media or cell extracts for 24 hours. To deliver DOs into the nuclei of human U2OS cells, we conjugated 30-nanometer DO nanorods with an antibody raised against a nuclear factor, specifically the largest subunit of RNA polymerase II (Pol II). We find that DOs remain structurally intact in cells for 24 hours, including inside the nucleus. We demonstrate that electroporated anti-Pol II antibody-conjugated DOs are piggybacked into nuclei and exhibit subdiffusive motion inside the nucleus. Our results establish interfacing DOs with a nuclear factor as an effective method to deliver nanodevices into live-cell nuclei.


Assuntos
Núcleo Celular , DNA , Nanoestruturas , Núcleo Celular/metabolismo , Humanos , DNA/química , DNA/metabolismo , Nanoestruturas/química , RNA Polimerase II/metabolismo , Linhagem Celular Tumoral , Nanotubos/química
14.
Phys Chem Chem Phys ; 26(24): 17255-17264, 2024 Jun 19.
Artigo em Inglês | MEDLINE | ID: mdl-38856309

RESUMO

Assessment of DFT methods is essential to sustain reliability in the computational investigation of complex transition metal oxides. This work evaluates the performance of the strongly constrained and appropriately normed (SCAN) functional and its extended Hubbard-U methodology (SCAN+U) to model the YSr2Cu2FeO7+δ (0 < δ < 1) perovskite-based system. The influence of the individual UCu and UFe Hubbard parameters (0 < U < 4 eV) on the calculated electronic, magnetic and crystal structures of the end members δ = 1 (metallic) and δ = 0 (insulating) is analyzed. The introduction of the U-correction terms enhances the reproduction of the crystal structures, with a UCu value of 1 eV improving the band gap accuracy for the YSr2Cu2FeO7 phase, while maintaining the metallic characteristics of YSr2Cu2FeO8. At a fixed UCu value, the results are almost insensitive to the UFe value used in the calculations. The findings emphasize that for oxides containing several TM ions, the optimal UTM values may differ from those of the simple TM oxides.

15.
Physiol Rep ; 12(12): e16094, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38924381

RESUMO

The renin-angiotensin system (RAS)-a classical blood pressure regulator-largely contributes to healthy organ development and function. Besides, RAS activation promotes age-related changes and age-associated diseases, which are attenuated/abolished by RAS-blockade in several mammalian species. RAS-blockers also increase rodent lifespan. In previous work, we discussed how RAS-blockade downregulates mTOR and growth hormone/IGF-1 signaling, and stimulates AMPK activity (together with klotho, sirtuin, and vitamin D-receptor upregulation), and proposed that at least some of RAS-blockade's aging benefits are mediated through regulation of these intermediaries and their signaling to mitochondria. Here, we included RAS-blockade's impact on other aging regulatory pathways, that is, TGF-ß, NF-kB, PI3K, MAPK, PKC, Notch, and Wnt, all of which affect mitochondria. No direct evidence is available on RAS/RAS-blockade-aging regulatory pathway-mitochondria interactions. However, existing results allow to conjecture that RAS-blockers neutralize mitochondrial dysfunction by acting on the discussed pathways. The reviewed evidence led us to propose that the foundation is laid for conducting clinical trials aimed at testing whether angiotensin-converting enzyme inhibitors (ACEi) or angiotensin receptor blockers (ARB)-even at subclinical doses-offer the possibility to live longer and in better health. As ACEi and ARB are low cost and well-tolerated anti-hypertension therapies in use for over 35 years, investigating their administration to attenuate/prevent aging effects seems simple to implement.


Assuntos
Envelhecimento , Inibidores da Enzima Conversora de Angiotensina , Sistema Renina-Angiotensina , Humanos , Sistema Renina-Angiotensina/efeitos dos fármacos , Envelhecimento/efeitos dos fármacos , Envelhecimento/metabolismo , Envelhecimento/fisiologia , Animais , Inibidores da Enzima Conversora de Angiotensina/farmacologia , Inibidores da Enzima Conversora de Angiotensina/uso terapêutico , Transdução de Sinais/efeitos dos fármacos , Mitocôndrias/metabolismo , Mitocôndrias/efeitos dos fármacos , Antagonistas de Receptores de Angiotensina/farmacologia , Antagonistas de Receptores de Angiotensina/uso terapêutico
17.
Geroscience ; 2024 Jun 20.
Artigo em Inglês | MEDLINE | ID: mdl-38900346

RESUMO

Little is known about the possibility of reversing age-related biological changes when they have already occurred. To explore this, we have characterized the effects of reducing insulin/IGF-1 signaling (IIS) during old age. Reduction of IIS throughout life slows age-related decline in diverse species, most strikingly in the nematode Caenorhabditis elegans. Here we show that even at advanced ages, auxin-induced degradation of DAF-2 in single tissues, including neurons and the intestine, is still able to markedly increase C. elegans lifespan. We describe how reversibility varies among senescent changes. While senescent pathologies that develop in mid-life were not reversed, there was a rejuvenation of the proteostasis network, manifesting as a restoration of the capacity to eliminate otherwise intractable protein aggregates that accumulate with age. Moreover, resistance to several stressors was restored. These results support several new conclusions. (1) Loss of resilience is not solely a consequence of pathologies that develop in earlier life. (2) Restoration of proteostasis and resilience by inhibiting IIS is a plausible cause of the increase in lifespan. And (3), most interestingly, some aspects of the age-related transition from resilience to frailty can be reversed to a certain extent. This raises the possibility that the effect of IIS and related pathways on resilience and frailty during aging in higher animals might possess some degree of reversibility.

18.
Sci Rep ; 14(1): 14652, 2024 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-38918538

RESUMO

The workflow to simulate motion with recorded data usually starts with selecting a generic musculoskeletal model and scaling it to represent subject-specific characteristics. Simulating muscle dynamics with muscle-tendon parameters computed from existing scaling methods in literature, however, yields some inconsistencies compared to measurable outcomes. For instance, simulating fiber lengths and muscle excitations during walking with linearly scaled parameters does not resemble established patterns in the literature. This study presents a tool that leverages reported in vivo experimental observations to tune muscle-tendon parameters and evaluates their influence in estimating muscle excitations and metabolic costs during walking. From a scaled generic musculoskeletal model, we tuned optimal fiber length, tendon slack length, and tendon stiffness to match reported fiber lengths from ultrasound imaging and muscle passive force-length relationships to match reported in vivo joint moment-angle relationships. With tuned parameters, muscle contracted more isometrically, and soleus's operating range was better estimated than with linearly scaled parameters. Also, with tuned parameters, on/off timing of nearly all muscles' excitations in the model agreed with reported electromyographic signals, and metabolic rate trajectories varied significantly throughout the gait cycle compared to linearly scaled parameters. Our tool, freely available online, can customize muscle-tendon parameters easily and be adapted to incorporate more experimental data.


Assuntos
Fibras Musculares Esqueléticas , Tendões , Tendões/fisiologia , Tendões/diagnóstico por imagem , Humanos , Fibras Musculares Esqueléticas/fisiologia , Músculo Esquelético/fisiologia , Fenômenos Biomecânicos , Caminhada/fisiologia , Marcha/fisiologia , Eletromiografia , Modelos Biológicos , Masculino , Simulação por Computador
19.
Biochem Pharmacol ; 227: 116401, 2024 Jun 28.
Artigo em Inglês | MEDLINE | ID: mdl-38945278

RESUMO

The peptide hormone relaxin plays a critical role in tissue remodeling in a variety of tissues through activation of its cognate receptor, RXFP1. Relaxin's ability to modify extracellular matrices has provided a strong rationale for treating fibrosis in a variety of tissues. Treatment with recombinant relaxin peptides in clinical studies of heart failure has not yet proven useful, likely due to the short half-life of infused peptide. To circumvent this particular pharmacokinetic pitfall we have used a Protein-in-Protein (PiP) antibody technology described previously, to insert a single-chain human relaxin construct into the complementarity-determining region (CDR) of an immunoglobulin G (IgG) backbone, creating a relaxin molecule with a half-life of ∼4-5 days in mice. Relaxin-PiP biologics displaced Europium-labeled human relaxin in RXFP1-expressing cells and demonstrated full agonist activity on both human and mouse RXFP1 receptors. Relaxin-PiPs did not show signal transduction bias, as they activated cAMP in THP-1 cells, and cGMP and pERK signaling in primary human cardiac fibroblasts. In an induced carbon tetrachloride mouse model of liver fibrosis one relaxin-PiP, R2-PiP, caused reduction of liver lesions, ameliorated collagen accumulation in the liver with the corresponding reduction of Collagen1a1 gene expression, and increased cell proliferation in hepatic parenchyma. These relaxin biologics represent a novel approach to the design of a long-acting RXFP1 agonist to probe the clinical utility of relaxin/RXFP1 signaling to treat a variety of human fibrotic diseases.

20.
Oral Dis ; 2024 Jun 27.
Artigo em Inglês | MEDLINE | ID: mdl-38938085

RESUMO

OBJECTIVE: Oral leukoplakia (OL) is one of the most common and investigated oral potentially malignant disorders (OPMD). Preventing OSCC occurrence should be the primary outcome in the clinical management of OL. Surgical removal of OL is performed by most clinicians, although its effectiveness in reducing OSCC onset has still not been established by randomized controlled trials (RCT). Wait and see approach is characterized by frequent clinical examinations and periodical biopsies of OL, avoiding unnecessary surgical procedures. This is the first multicenter RCT in literature aiming at comparing the effectiveness of surgical removal and the "wait and see" approach in preventing OSCC onset in patients affected by dysplastic and non-dysplastic OL. METHODS: Two Italian referral care centres for oral diseases were involved in this multicenter two-arm RCT comparing the surgical removal of OL (group A) and the "wait and see" approach (group B), with the aim of reducing oral cancer onset. RESULTS: This report shows preliminary data on the first 161 patients, with a mean follow-up of 19.14 ± 11.25 months. Eight cases of OSCC occurred (6 out 8 involving the tongue): one case in group A and seven cases in group B. Moreover, OL recurred in 13 (20%) cases after surgical excision. CONCLUSIONS: Within the limitations of this preliminary report, these initial data underline the increased risk of OSCC onset in the case of OL of the tongue in the presence of epithelial dysplasia in group B ("wait and see") compared to group A (surgery). This RCT is currently ongoing at the same clinical departments, with the aim of enrolling 310 patients and collecting data at 5-year follow-up, in order to achieve conclusive results, in an evidence-based medicine approach.

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