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1.
Braz J Biol ; 84: e281973, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38836802

RESUMO

Agricultural management using technologies that help farmers increase productivity and reduce production costs must be promoted to ensure agricultural sustainability. The objective of the study was to achieve the pH effect of growth solution, chemical treatment, use of osmoprotector additive and mineral nitrate presence, on the activity of growth promoting bacteria, Azospirillum brasilense, and its effects on the physiological quality of seeds and wheat seedling growth. The first experiment evaluated the physiological quality of seeds and the second experiment was divided into four, evaluating the growth of wheat seedling in a hydroponic system. The experiments were prolonged in a very randomized design, with four replications. The physiological quality of the seeds was evaluated by germination tests, first germination count, length of the shoot and root and dry mass of the shoot and root. Initial growth was evaluated by quantifying the dry mass of the leaf shoot and root and the root system intervals. The pH of the solution and the presence of nitrogen did not influence the effects of inoculation of the A. brasilense bacteria. With the use of chemical treatment and osmoprotective additive, A. brasilense had no effect on the growth of wheat seedlings.


Assuntos
Azospirillum brasilense , Meios de Cultura , Germinação , Plântula , Triticum , Triticum/microbiologia , Triticum/crescimento & desenvolvimento , Azospirillum brasilense/fisiologia , Plântula/crescimento & desenvolvimento , Plântula/microbiologia , Germinação/fisiologia , Concentração de Íons de Hidrogênio
2.
Artigo em Inglês | MEDLINE | ID: mdl-38842369

RESUMO

BACKGROUND: High-velocity concentric actions can be negatively impacted by cumulative fatigue during plyometric training. Reducing vertical ground reaction forces (GRF) upon landing could decrease eccentric demands, potentially minimizing fatigue, maintaining concentric performance, and benefiting concentric training adaptations. Therefore, this study examined the effect of intentionally higher and lower landing vertical GRF on the ability to sustain concentric jumping performance. METHODS: Twenty men (25.2±3.5 years) performed 30 maximal effort jumps over a 50 cm hurdle (high-landing GRF) and onto a 50 cm box (low-landing GRF), on two separate occasions in a counter-balanced order. Jumps were measured using two force platforms (one for takeoff and one for landing) and a linear position transducer. The 30 jumps were divided into 5 groups of 6 repetitions, and the mean value for each group was analyzed. RESULTS: There was no significant condition × repetition group interaction for any parameters, indicating that the greater landing GRF during hurdle jumps did not negatively affect concentric jump performance throughout the 30 jumps. Concentric velocities and jump height were significantly greater during box jumps compared to hurdle jumps. CONCLUSIONS: Thirty maximal-effort jumps did not cause fatigue-related decrease of performance, independent of jump type (i.e., the magnitude of landing GRF). Although, reduced vertical GRF upon landing appears to have a neutral-to-positive effect on concentric jumping performance. Therefore, reducing landing GRF, such as by using BJs, could acutely augment jumping performance and help to reduce cumulative training load.

3.
Chemistry ; : e202402010, 2024 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-38855991

RESUMO

We report herein of a novel, enantioselective and rhodium- catalyzed cyclisation of allenyl alcohols towards chiral α-vinylic, cyclic ethers employing a rhodium/(R,R)-Me-ferrocelane catalyst. The corresponding chiral cyclic products were obtained in general high yield and enantioselectivities. The synthetic value of our obtained products was further exemplified by transformations of the allylic ether function. Furthermore, applying our newly developed method in our previously reported route towards the total synthesis of (R,R,R)-α-tocopherol, we were able to devise a significantly improved 2nd generation total synthesis with 12 steps in the longest linear sequence and an overall total yield of 24%.

4.
Phys Rev Lett ; 132(21): 216601, 2024 May 24.
Artigo em Inglês | MEDLINE | ID: mdl-38856285

RESUMO

Anyons are particles intermediate between fermions and bosons, characterized by a nontrivial exchange phase, yielding remarkable braiding statistics. Recent experiments have shown that anyonic braiding has observable consequences on edge transport in the fractional quantum Hall effect (FQHE). Here, we study transport signatures of anyonic braiding when the anyons have a finite width. We show that the width of the anyons, even when extremely small, can have a tremendous impact on transport properties and braiding signatures. In particular, we find that taking the finite width into account allows us to explain recent experimental results on the FQHE at filling factor 2/5 [M. Ruelle et al., Phys. Rev. X 13, 011031 (2023)PRXHAE2160-330810.1103/PhysRevX.13.011031]. Our work shows that the finite width of anyons crucially influences setups involving anyonic braiding, especially when the exchange phase is larger than π/2.

5.
Microbiol Spectr ; : e0104524, 2024 Jun 25.
Artigo em Inglês | MEDLINE | ID: mdl-38916314

RESUMO

Fungal infections are a major contributor to morbidity and mortality among immunocompromised populations. Moreover, fungal disease caused by molds are difficult to treat and are associated with particularly high mortality. To address the need for new mold-active antifungal drugs, we performed a high-throughput screen with Aspergillus fumigatus, the most common pathogenic mold. We identified a novel, pyrimidine-based chemical scaffold with broad-spectrum antifungal activity including activity against several difficult-to-treat molds. A chemical genetics screen of Saccharomyces cerevisiae suggested that this compound may target the endoplasmic reticulum (ER) and perturb ER function and/or homeostasis. Consistent with this model, this compound induces the unfolded protein response and inhibits secretion of A. fumigatus collagenases. Initial cytotoxicity and pharmacokinetic studies show favorable features including limited mammalian cell toxicity and bioavailability in vivo. Together, these data support the further medicinal chemistry and pre-clinical development of this pyrimidine scaffold toward more effective treatments for life-threatening invasive mold infections.IMPORTANCEInvasive fungal diseases are life-threatening infections caused by fungi in immunocompromised individuals. Currently, there are only three major classes of antifungal drugs available to treat fungal infections; however, these options are becoming even more limited with the global emergence of antifungal drug resistance. To address the need for new antifungal therapies, we performed a screen of chemical compounds and identified a novel molecule with antifungal activity. Initial characterization of this compound shows drug-like features and broad-spectrum activity against medically important fungi. Together, our results support the continued development of this compound as a potential future therapy for these devastating fungal infections.

6.
Virus Res ; 346: 199399, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38823688

RESUMO

Coronaviruses have caused three severe epidemics since the start of the 21st century: SARS, MERS and COVID-19. The severity of the ongoing COVID-19 pandemic and increasing likelihood of future coronavirus outbreaks motivates greater understanding of factors leading to severe coronavirus disease. We screened ten strains from the Collaborative Cross mouse genetic reference panel and identified strains CC006/TauUnc (CC006) and CC044/Unc (CC044) as coronavirus-susceptible and resistant, respectively, as indicated by variable weight loss and lung congestion scores four days post-infection. We generated a genetic mapping population of 755 CC006xCC044 F2 mice and exposed the mice to one of three genetically distinct mouse-adapted coronaviruses: clade 1a SARS-CoV MA15 (n=391), clade 1b SARS-CoV-2 MA10 (n=274), and clade 2 HKU3-CoV MA (n=90). Quantitative trait loci (QTL) mapping in SARS-CoV MA15- and SARS-CoV-2 MA10-infected F2 mice identified genetic loci associated with disease severity. Specifically, we identified seven loci associated with variation in outcome following infection with either virus, including one, HrS43, that is present in both groups. Three of these QTL, including HrS43, were also associated with HKU3-CoV MA outcome. HrS43 overlaps with a QTL previously reported by our lab that is associated with SARS-CoV MA15 outcome in CC011xCC074 F2 mice and is also syntenic with a human chromosomal region associated with severe COVID-19 outcomes in humans GWAS. The results reported here provide: (a) additional support for the involvement of this locus in SARS-CoV MA15 infection, (b) the first conclusive evidence that this locus is associated with susceptibility across the Sarbecovirus subgenus, and (c) demonstration of the relevance of mouse models in the study of coronavirus disease susceptibility in humans.


Assuntos
COVID-19 , Modelos Animais de Doenças , Locos de Características Quantitativas , SARS-CoV-2 , Animais , Camundongos , SARS-CoV-2/genética , COVID-19/virologia , Suscetibilidade a Doenças , Humanos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/genética , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/patogenicidade , Mapeamento Cromossômico , Infecções por Coronavirus/virologia , Feminino , Camundongos de Cruzamento Colaborativo/genética , Predisposição Genética para Doença , Masculino
7.
bioRxiv ; 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38895248

RESUMO

Multiple sclerosis (MS) is a complex disease with significant heterogeneity in disease course and progression. Genetic studies have identified numerous loci associated with MS risk, but the genetic basis of disease progression remains elusive. To address this, we leveraged the Collaborative Cross (CC), a genetically diverse mouse strain panel, and experimental autoimmune encephalomyelitis (EAE). The thirty-two CC strains studied captured a wide spectrum of EAE severity, trajectory, and presentation, including severe-progressive, monophasic, relapsing remitting, and axial rotary (AR)-EAE, accompanied by distinct immunopathology. Sex differences in EAE severity were observed in six strains. Quantitative trait locus analysis revealed distinct genetic linkage patterns for different EAE phenotypes, including EAE severity and incidence of AR-EAE. Machine learning-based approaches prioritized candidate genes for loci underlying EAE severity ( Abcc4 and Gpc6 ) and AR-EAE ( Yap1 and Dync2h1 ). This work expands the EAE phenotypic repertoire and identifies novel loci controlling unique EAE phenotypes, supporting the hypothesis that heterogeneity in MS disease course is driven by genetic variation. Summary: The genetic basis of disease heterogeneity in multiple sclerosis (MS) remains elusive. We leveraged the Collaborative Cross to expand the phenotypic repertoire of the experimental autoimmune encephalomyelitis (EAE) model of MS and identify loci controlling EAE severity, trajectory, and presentation.

8.
bioRxiv ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38798314

RESUMO

Opioid use disorder is heritable, yet its genetic etiology is largely unknown. Analysis of addiction model traits in rodents (e.g., opioid behavioral sensitivity and withdrawal) can facilitate genetic and mechanistic discovery. C57BL/6J and C57BL/6NJ substrains have extremely limited genetic diversity, yet can show reliable phenotypic diversity which together, can facilitate gene discovery. The C57BL/6NJ substrain was less sensitive to oxycodone (OXY)-induced locomotor activity compared to the C57BL/6J substrain. Quantitative trait locus (QTL) mapping in an F2 cross identified a distal chromosome 1 QTL explaining 7-12% of the variance in OXY locomotor sensitivity and anxiety-like withdrawal in the elevated plus maze. We identified a second QTL for withdrawal on chromosome 5 near the candidate gene Gabra2 (alpha-2 subunit of GABA-A receptor) explaining 9% of the variance. Next, we generated recombinant lines from an F2 founder spanning the distal chromosome 1 locus (163-181 Mb), captured the QTL for OXY sensitivity and withdrawal, and fine-mapped a 2.45-Mb region (170.16-172.61 Mb). There were five striatal cis-eQTL transcripts in this region (Pcp4l1, Ncstn, Atp1a2, Kcnj9, Igsf9), two of which were confirmed at the protein level (KCNJ9, ATP1A2). Kcnj9, a.k.a., GIRK3, codes for a potassium channel that is a major effector of mu opioid receptor signaling. Atp1a2 codes for a subunit of a Na+/K+ ATPase enzyme that regulates neuronal excitability and shows adaptations following chronic opioid administration. To summarize, we identified genetic sources of opioid behavioral differences in C57BL/6 substrains, two of the most widely and often interchangeably used substrains in opioid addiction research.

9.
medRxiv ; 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38798476

RESUMO

Background: Hepatitis C virus (HCV) elimination requires treatment access expansion, especially for underserved populations. Telehealth has the potential to improve HCV treatment access, although data are limited on its incorporation into standard clinical practice. Methods: We conducted a cross-sectional, e-mail survey of 598 US HCV treatment providers who had valid email addresses and 1) were located in urban areas and had written ≥20 prescriptions for HCV treatment to US Medicare beneficiaries in 2019-20 or 2) were located in non-urban areas and wrote any HCV prescriptions in 2019-20. Through email, we notified providers of a self-administered electronic 28-item survey of clinical strategies and attitudes about telemedicine for HCV. Results: We received 86 responses (14% response rate), of which 75 used telemedicine for HCV in 2022. Of those 75, 24% were gastroenterologists/hepatologists, 23% general medicine, 17% infectious diseases, and 32% non-physicians. Most (82%) referred patients to commercial laboratories, and 85% had medications delivered directly to patients. Overwhelmingly, respondents (92%) felt that telehealth increases healthcare access, and 76% reported that it promotes or is neutral for treatment completion. Factors believed to be "extremely" or "very" important for telehealth use included patient access to technology (86%); patients' internet access (74%); laboratory access (76%); reimbursement for video visits (74%) and audio-only visits (66%). Non-physician licensing and liability statutes were rated "extremely" or "very" important by 43% and 44%, respectively. Conclusions: Providers felt that telehealth increases HCV treatment access. Major limitations were technological requirements, reimbursement, and access to ancillary services. These findings support the importance of digital equity and literacy to achieve HCV elimination goals.

10.
J Phys Chem A ; 128(19): 3830-3839, 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38709806

RESUMO

As important naturally occurring chromophores, photophysical/chemical properties of quinoid flavins have been extensively studied both experimentally and theoretically. However, little is known about the transition dipole moment (TDM) orientation of excited-state absorption transitions of these important compounds. This aspect is of high interest in the fields of photocatalysis and quantum control studies. In this work, we employ polarization-associated spectra (PAS) to study the excited-state absorption transitions and the underlying TDM directions of a standard quinoid flavin compound. As compared to transient absorption anisotropy (TAA), an analysis based on PAS not only avoids diverging signals but also retrieves the relative angle for ESA transitions with respect to known TDM directions. Quantum chemical calculations of excited-state properties lead to good agreement with TA signals measured in magic angle configuration. Only when comparing experiment and theory for TAA spectra and PAS, do we find deviations when and only when the S0 → S1 of flavin is used as a reference. We attribute this to the vibronic coupling of this transition to a dark state. This effect is only observed in the employed polarization-controlled spectroscopy and would have gone unnoticed in conventional TA.

11.
Nat Commun ; 15(1): 3738, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702297

RESUMO

Whole virus-based inactivated SARS-CoV-2 vaccines adjuvanted with aluminum hydroxide have been critical to the COVID-19 pandemic response. Although these vaccines are protective against homologous coronavirus infection, the emergence of novel variants and the presence of large zoonotic reservoirs harboring novel heterologous coronaviruses provide significant opportunities for vaccine breakthrough, which raises the risk of adverse outcomes like vaccine-associated enhanced respiratory disease. Here, we use a female mouse model of coronavirus disease to evaluate inactivated vaccine performance against either homologous challenge with SARS-CoV-2 or heterologous challenge with a bat-derived coronavirus that represents a potential emerging disease threat. We show that inactivated SARS-CoV-2 vaccines adjuvanted with aluminum hydroxide can cause enhanced respiratory disease during heterologous infection, while use of an alternative adjuvant does not drive disease and promotes heterologous viral clearance. In this work, we highlight the impact of adjuvant selection on inactivated vaccine safety and efficacy against heterologous coronavirus infection.


Assuntos
Hidróxido de Alumínio , Vacinas contra COVID-19 , COVID-19 , SARS-CoV-2 , Vacinas de Produtos Inativados , Animais , Vacinas contra COVID-19/imunologia , Vacinas contra COVID-19/administração & dosagem , Feminino , COVID-19/prevenção & controle , COVID-19/imunologia , COVID-19/virologia , Camundongos , Vacinas de Produtos Inativados/imunologia , SARS-CoV-2/imunologia , Hidróxido de Alumínio/administração & dosagem , Modelos Animais de Doenças , Adjuvantes Imunológicos/administração & dosagem , Adjuvantes de Vacinas , Anticorpos Antivirais/imunologia , Camundongos Endogâmicos BALB C , Humanos , Coronavírus Relacionado à Síndrome Respiratória Aguda Grave/imunologia
12.
Pediatr Radiol ; 2024 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-38671145

RESUMO

Bone marrow metastases-noted in 6% of patients with rhabdomyosarcoma-have been linked to very poor outcomes. Bilateral bone marrow sampling from iliac crests has been the gold standard for bone marrow examination in rhabdomyosarcoma, but sampling errors due to patchy bone marrow involvement may limit its sensitivity. Here, we report the case of a 6-year-old boy with embryonal rhabdomyosarcoma of the skull base and multiple 2-[18F]fluoro-2-deoxy-D-glucose (2-[18F]FDG)-avid bone marrow metastases visualized by positron emission tomography and computed tomography (2-[18F]FDG PET/CT). His bone marrow aspirates were tumor-free. This case illustrates the diagnostic value of 2-[18F]FDG PET/CT in the detection of bone marrow metastases in rhabdomyosarcoma patients, which may re-shape the definition of bone marrow disease and, ultimately, alter disease staging and risk stratification.

13.
Artigo em Inglês | MEDLINE | ID: mdl-38670234

RESUMO

BACKGROUND: The development of peanut allergy is due to a combination of genetic and environmental factors, although specific genes have proven difficult to identify. Previously, we reported that peanut-sensitized Collaborative Cross strain CC027/GeniUnc (CC027) mice develop anaphylaxis upon oral challenge to peanut, in contrast to C3H/HeJ (C3H) mice. OBJECTIVE: This study aimed to determine the genetic basis of orally induced anaphylaxis to peanut in CC027 mice. METHODS: A genetic mapping population between CC027 and C3H mice was designed to identify the genetic factors that drive oral anaphylaxis. A total of 356 CC027xC3H backcrossed mice were generated, sensitized to peanut, then challenged to peanut by oral gavage. Anaphylaxis and peanut-specific IgE were quantified for all mice. T-cell phenotyping was conducted on CC027 mice and 5 additional Collaborative Cross strains. RESULTS: Anaphylaxis to peanut was absent in 77% of backcrossed mice, with 19% showing moderate anaphylaxis and 4% having severe anaphylaxis. There were 8 genetic loci associated with variation in response to peanut challenge-6 associated with anaphylaxis (temperature decrease) and 2 associated with peanut-specific IgE levels. There were 2 major loci that impacted multiple aspects of the severity of acute anaphylaxis, at which the CC027 allele was associated with worse outcome. At one of these loci, CC027 has a private genetic variant in the Themis gene. Consistent with described functions of Themis, we found that CC027 mice have more immature T cells with fewer CD8+, CD4+, and CD4+CD25+CD127- regulatory T cells. CONCLUSIONS: Our results demonstrate a key role for Themis in the orally reactive CC027 mouse model of peanut allergy.

14.
Viruses ; 16(4)2024 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-38675976

RESUMO

RNA viruses quickly evolve subtle genotypic changes that can have major impacts on viral fitness and host range, with potential consequences for human health. It is therefore important to understand the evolutionary fitness of novel viral variants relative to well-studied genotypes of epidemic viruses. Competition assays are an effective and rigorous system with which to assess the relative fitness of viral genotypes. However, it is challenging to quickly and cheaply distinguish and quantify fitness differences between very similar viral genotypes. Here, we describe a protocol for using reverse transcription PCR in combination with commercial nanopore sequencing services to perform competition assays on untagged RNA viruses. Our assay, called the Universal Competition Assay by Nanopore Sequencing (U-CAN-seq), is relatively cheap and highly sensitive. We used a well-studied N24A mutation in the chikungunya virus (CHIKV) nsp3 gene to confirm that we could detect a competitive disadvantage using U-CAN-seq. We also used this approach to show that mutations to the CHIKV 5' conserved sequence element that disrupt sequence but not structure did not affect the fitness of CHIKV. However, similar mutations to an adjacent CHIKV stem loop (SL3) did cause a fitness disadvantage compared to wild-type CHIKV, suggesting that structure-independent, primary sequence determinants in this loop play an important role in CHIKV biology. Our novel findings illustrate the utility of the U-CAN-seq competition assay.


Assuntos
Vírus Chikungunya , Mutação , Sequenciamento por Nanoporos , Sequenciamento por Nanoporos/métodos , Vírus Chikungunya/genética , Vírus Chikungunya/classificação , Humanos , Genótipo , Aptidão Genética , RNA Viral/genética , Animais , Vírus de RNA/genética , Vírus de RNA/classificação , Febre de Chikungunya/virologia
15.
Cell Rep ; 43(5): 114127, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38652660

RESUMO

Ebola virus (EBOV), a major global health concern, causes severe, often fatal EBOV disease (EVD) in humans. Host genetic variation plays a critical role, yet the identity of host susceptibility loci in mammals remains unknown. Using genetic reference populations, we generate an F2 mapping cohort to identify host susceptibility loci that regulate EVD. While disease-resistant mice display minimal pathogenesis, susceptible mice display severe liver pathology consistent with EVD-like disease and transcriptional signatures associated with inflammatory and liver metabolic processes. A significant quantitative trait locus (QTL) for virus RNA load in blood is identified in chromosome (chr)8, and a severe clinical disease and mortality QTL is mapped to chr7, which includes the Trim5 locus. Using knockout mice, we validate the Trim5 locus as one potential driver of liver failure and mortality after infection. The identification of susceptibility loci provides insight into molecular genetic mechanisms regulating EVD progression and severity, potentially informing therapeutics and vaccination strategies.


Assuntos
Ebolavirus , Predisposição Genética para Doença , Doença pelo Vírus Ebola , Locos de Características Quantitativas , Animais , Doença pelo Vírus Ebola/virologia , Doença pelo Vírus Ebola/genética , Doença pelo Vírus Ebola/patologia , Locos de Características Quantitativas/genética , Ebolavirus/patogenicidade , Ebolavirus/genética , Camundongos , Camundongos Knockout , Mapeamento Cromossômico , Fígado/patologia , Fígado/metabolismo , Humanos , Camundongos Endogâmicos C57BL , Feminino , Masculino
16.
J Cardiothorac Surg ; 19(1): 239, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632653

RESUMO

OBJECTIVES: Aortic pathologies often present with elevated inflammatory biomarkers due to the nature of the disease. Open aortic surgery causes significant trauma to the body due to often mandatory ischemic periods, long cardiopulmonary bypass times and polytransfusion. We aim to determine postoperative trends on inflammation biomarkers for different aortic pathologies and type of surgery in different segments of the aorta. METHODS: Retrospective review of prospectively collected data of 193 consecutive patients who underwent aortic surgery in our centre between 2017 and 2021, grouped according to the type of aortic intervention: (1) Type A aortic dissection (AD) repair with ascending aorta/hemiarch replacement, (2) Aortic root replacement (ARR), (3) Aortic arch + Frozen elephant trunk (FET), (4) Descending thoracic aorta (DTA)/Thoraco-Abdominal aortic repair (TAA). Primary outcomes were daily values of white blood cells (WBC) and C-Reactive Protein (CRP) during the first 15 postoperative days. RESULTS: All groups had a similar inflammatory peak in the first 2-4 days (WBC 12-15 × 109 c/L). AD and FET groups show similar trends with WBC and CRP peaks on days 2 and 10. The ARR group didn't experience the 2nd peak as most patients were already discharged. DTA/TAA patients experienced a more prolonged inflammatory response, reaching a plateau by day 5-10. AD group shows the highest WBC levels and the DTA/TAAA group the highest CRP levels. CRP levels remain elevated (100-200 mg/L) in all groups after 15 postoperative days. CONCLUSIONS: Inflammatory biomarkers show different postoperative trends depending on the clinical presentation and complexity of the aortic procedure performed. Further understanding of the inflammatory response to different aortic pathologies and surgical procedures will permit reduction on the liberal use of antibiotics that this cohort of patients are usually exposed to. An earlier version of the data included in this manuscript was presented as Oral Abstract in the UK Society of Cardiothoracic Surgery Annual meeting in 2021.


Assuntos
Aneurisma da Aorta Torácica , Implante de Prótese Vascular , Humanos , Implante de Prótese Vascular/métodos , Aorta/cirurgia , Aorta Torácica/cirurgia , Estudos Retrospectivos , Inflamação , Biomarcadores , Aneurisma da Aorta Torácica/cirurgia , Resultado do Tratamento , Prótese Vascular
17.
bioRxiv ; 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38562845

RESUMO

The obligate intracellular parasite Toxoplasma gondii can infect and replicate in any warm-blooded cell tested to date, but much of our knowledge about T. gondii cell biology comes from just one host cell type: human foreskin fibroblasts (HFFs). To expand our knowledge of host-parasite lipid interactions, we studied T. gondii in intestinal epithelial cells, the first site of host-parasite contact following oral infection and the exclusive site of parasite sexual development in feline hosts. We found that highly metabolic Caco-2 cells are permissive to T. gondii growth even when treated with high levels of linoleic acid (LA), a polyunsaturated fatty acid (PUFA) that kills parasites in HFFs. Caco-2 cells appear to sequester LA away from the parasite, preventing membrane disruptions and lipotoxicity that characterize LA-induced parasite death in HFFs. Our work is an important step toward understanding host-parasite interactions in feline intestinal epithelial cells, an understudied but important cell type in the T. gondii life cycle.

18.
Support Care Cancer ; 32(5): 319, 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38689167

RESUMO

PURPOSE: Cancer-related fatigue (CRF) is a common side effect of cancer and cancer treatment that significantly impairs the quality of life and can persist for years after treatment completion. Although fatigue is often associated with cancer treatment, it is also a result of the disease itself, even before intervention. CRF at the time of diagnosis may affect treatment timing or completion and is a consistent predictor of post-treatment fatigue at any time. The mechanisms underlying CRF are multidimensional and not well understood, particularly at the time of diagnosis. METHODS: Sixty-five breast cancer patients at the time of diagnosis were included. The participants completed self-assessment questionnaires about CRF, sleep disturbances, and emotional symptoms and wore an accelerometer to assess levels of spontaneous physical activity and sleep quality. During the experimental session, the participants underwent cognitive, neuromuscular, and exercise metabolism evaluations. RESULTS: Using augmented backward elimination regression, this study found that emotional symptoms and perceived sleep disturbances were the strongest predictors of CRF (adjusted r2 = 0.51). Neuromuscular fatigability and sleep disturbance were also associated with physical dimensions, whereas cognitive performance was associated with cognitive dimensions. CONCLUSION: At the time of diagnosis, emotional and cognitive dimensions are over-represented compared to the general population, and specific subdimensions have specific predictors that support the idea of distinct mechanisms. Evaluating CRF subdimensions and their potential mechanisms at the time of diagnosis would be particularly relevant for identifying high-risk patients and offering them appropriate interventions. TRIAL REGISTRATION: This study was registered at ClinicalTrials.gov (NCT04391543) in May, 2020.


Assuntos
Neoplasias da Mama , Fadiga , Transtornos do Sono-Vigília , Humanos , Fadiga/etiologia , Fadiga/diagnóstico , Feminino , Pessoa de Meia-Idade , Inquéritos e Questionários , Neoplasias da Mama/complicações , Adulto , Transtornos do Sono-Vigília/etiologia , Idoso , Estudos de Coortes , Qualidade de Vida , Exercício Físico/fisiologia , Qualidade do Sono
19.
HCA Healthc J Med ; 5(1): 39-43, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38560396

RESUMO

Introduction: Primary mucinous carcinoma of the thyroid is an exceedingly rare malignancy that is histologically similar to mucinous carcinoma of other sites. Accurate diagnosis is a challenging yet crucial component of clinical management for both patients and our understanding of this rare disease. Case Presentation: We report the case of a 69-year-old male patient with primary mucinous carcinoma of the thyroid. Microscopic examination of a biopsy specimen showed fibrous tissue, which was extensively and irregularly infiltrated by a cytologically malignant epithelial neoplasm showing glandular differentiation with mucin production. Immunohistochemistry demonstrated that tumor cells were positive for TTF1, thyroglobulin, CK7, and PAX8. Co-expression of TTF1 and PAX8 is most commonly seen in thyroid tumors. These findings support our diagnosis of mucinous carcinoma of thyroid origin, which is rare and highly aggressive. Conclusion: In this report, we present the only documented case of primary mucinous carcinoma of the thyroid reported in the United States in the last decade. The diagnosis of primary mucinous carcinoma of the thyroid can be challenging. Therefore, we discuss and detail the clinicopathologic tumor profile and provide more current, detailed histological criteria to assist in the diagnosis of this rare disease.

20.
Theranostics ; 14(6): 2560-2572, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38646643

RESUMO

Management of prostate cancer (PC) might be improved by combining external beam radiotherapy (EBRT) and prostate-specific membrane antigen (PSMA)-targeted radioligand therapy (RLT) with lutetium-177 (177Lu)-labeled PSMA inhibitors. We hypothesized a higher efficacy of the combination due to augmentation of the radiation dose to the tumor and interactions of EBRT with PSMA expression potentially increasing radiopharmaceutical uptake. Therefore, this study analyzed the influence of radiation on PSMA expression levels in vitro. The results were translated to evaluate the efficacy of the combination of photon EBRT and [177Lu]Lu-PSMA-617 in a murine PC xenograft model. Finally, a clinical case report on a combined elective field EBRT with RLT dose escalation illustrates a proof-of-concept. Methods: PSMA gene and protein expression were assessed in human PSMA-overexpressing LNCaP cells after irradiation using reverse transcription quantitative polymerase chain reaction (RT-qPCR), flow cytometry and On-Cell Western assays. In the in vivo therapy study, LNCaP tumor-bearing BALB/c nu/nu mice were irradiated once with 2 Gy X-ray EBRT and injected with 40 MBq [177Lu]Lu-PSMA-617 after 4 h or received single or no treatment (n = 10 each). Tumor-absorbed doses by [177Lu]Lu-PSMA-617 were calculated according to the Medical Internal Radiation Dosimetry (MIRD) formalism after deriving time-activity curves using a gamma probe. An exemplified patient case is demonstrated where fractionated EBRT (54 Gy to prostate; 45 Gy to pelvic lymphatics) and three cycles of [177Lu]Lu-PSMA-617 (3.4-6.0 GBq per cycle) were sequentially combined under concurrent androgen deprivation for treating locally advanced PC. Results: At 4 h following irradiation with 2-8 Gy, LNCaP cells displayed a PSMA protein upregulation by around 18% relative to non-irradiated cells, and a stronger upregulation on mRNA level (up to 2.6-fold). This effect was reversed by 24 h when PSMA protein levels were downregulated by up to 22%. Mice treated with the combination therapy showed significantly improved outcomes regarding tumor control and median survival (p < 0.0001) as compared to single or no treatment. Relative to monotherapy with PSMA-RLT or EBRT, the tumor doubling time was prolonged 1.7- or 2.7-fold and the median survival was extended by 24% or 60% with the combination, respectively. Additionally, tumors treated with EBRT exhibited a 14% higher uptake of the radiopharmaceutical as evident from the calculated tumor-absorbed dose, albeit with high variability in the data. Concerning the patient case, the tri-modality treatment was well tolerated and the patient responded with a long-lasting complete biochemical remission for five years following end of PSMA-RLT. The patient then developed a biochemical relapse with oligo-recurrent disease on follow-up imaging. Conclusion: The present preclinical and clinical data demonstrate that the combination of EBRT with dose escalation by PSMA-RLT improves tumor control and potentially prolongs survival. This may pave the way for further clinical investigations of this approach to explore the curative potential of the combination therapy.


Assuntos
Dipeptídeos , Compostos Heterocíclicos com 1 Anel , Lutécio , Antígeno Prostático Específico , Neoplasias da Próstata , Radioisótopos , Compostos Radiofarmacêuticos , Animais , Masculino , Neoplasias da Próstata/radioterapia , Neoplasias da Próstata/metabolismo , Humanos , Lutécio/uso terapêutico , Lutécio/farmacologia , Compostos Heterocíclicos com 1 Anel/uso terapêutico , Compostos Heterocíclicos com 1 Anel/farmacologia , Dipeptídeos/farmacologia , Dipeptídeos/uso terapêutico , Linhagem Celular Tumoral , Camundongos , Compostos Radiofarmacêuticos/uso terapêutico , Compostos Radiofarmacêuticos/farmacologia , Compostos Radiofarmacêuticos/farmacocinética , Radioisótopos/uso terapêutico , Radioisótopos/farmacologia , Camundongos Endogâmicos BALB C , Camundongos Nus , Glutamato Carboxipeptidase II/metabolismo , Glutamato Carboxipeptidase II/genética , Ensaios Antitumorais Modelo de Xenoenxerto , Antígenos de Superfície/metabolismo , Antígenos de Superfície/genética
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