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2.
Geobiology ; 22(4): e12610, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38979799

RESUMO

This study investigates the paleobiological significance of pyritic stromatolites from the 3.48 billion-year-old Dresser Formation, Pilbara Craton. By combining paleoenvironmental analyses with observations from well-preserved stromatolites in newly obtained drill cores, the research reveals stratiform and columnar to domal pyritic structures with wavy to wrinkly laminations and crest thickening, hosted within facies variably influenced by syn-depositional hydrothermal activity. The columnar and domal stromatolites occur in strata with clearly distinguishable primary depositional textures. Mineralogical variability and fine-scale interference textures between the microbialites and the enclosing sediment highlight interplays between microbial and depositional processes. The stromatolites consist of organomineralization - nanoporous pyrite and microspherulitic barite - hosting significant thermally mature organic matter (OM). This includes filamentous organic microstructures encased within nanoporous pyrite, resembling the extracellular polymeric substance (EPS) of microbes. These findings imply biogenicity and support the activity of microbial life in a volcano-sedimentary environment with hydrothermal activity and evaporative cycles. Coupled changes in stromatolite morphology and host facies suggest growth in diverse niches, from dynamic, hydrothermally influenced shallow-water environments to restricted brine pools strongly enriched in SO 4 2 - $$ {\mathrm{SO}}_4^{2-} $$ from seawater and hydrothermal activity. These observations, along with S stable isotope data indicating influence by S metabolisms, and accumulations of biologically significant metals and metalloids (Ni and As) within the microbialites, help constrain microbial processes. Columnar to domal stromatolites in dynamic, hydrothermally influenced shallow water deposits likely formed by microbial communities dominated by phototrophs. Stratiform pyritic structures within barite-rich strata may reflect the prevalence of chemotrophs near hydrothermal venting, where hydrothermal activity and microbial processes influenced barite precipitation. Rapid pyrite precipitation, a putative taphonomic process for preserving microbial remnants, is attributed to microbial sulfate reduction and reduced S sourced from hydrothermal activity. In conclusion, this research underscores the biogenicity of the Dresser stromatolites and advances our understanding of microbial ecosystems in Earth's early history.


Assuntos
Ecossistema , Sedimentos Geológicos , Sedimentos Geológicos/microbiologia , Sedimentos Geológicos/química , Sulfetos/química , Sulfetos/metabolismo , Fósseis , Ferro/metabolismo , Ferro/química
3.
Microbiol Spectr ; : e0030724, 2024 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-38980027

RESUMO

Detection of HIV infection may be challenging in persons using long-acting cabotegravir (CAB-LA) pre-exposure prophylaxis (PrEP) due to viral suppression and reduced/delayed antibody production. We evaluated two point-of-care tests for detecting HIV infection in persons who received CAB-LA in the HPTN 083 trial. Samples were obtained from 12 participants who received CAB-LA and had delayed detection of HIV infection using HIV rapid tests and an antigen/antibody test (52 plasma samples; 18 dried blood spot [DBS] samples). Plasma samples were tested with the Xpert HIV-1 Viral Load XC test (Xpert VL-XC); DBS samples were tested with the total nucleic acid Xpert HIV-1 Qual XC test (Xpert Qual-XC). Results from these assays were compared to results from three reference, laboratory-based, plasma RNA assays (Aptima HIV-1 Qualitative assay [Aptima Qual]; Aptima HIV-1 Quant DX Assay [Aptima Quant]; cobas HIV-1/HIV-2 Qualitative Test [cobas]). HIV RNA was detected with all four plasma assays for all samples with viral loads (VLs) ≥ 200 copies/mL; the number of samples with VLs < 200 copies/mL with HIV RNA detected was: Xpert VL-XC: 19/26 (73.1%); Aptima Qual: 17/26 (65.4%); Aptima Quant: 17/26 (65.4%); and cobas: 12/21 (57.1%). The Xpert Qual-XC assay was positive for all DBS samples with VLs ≥ 200 copies/mL and 1/10 DBS with VLs < 200 copies/mL. The performance of the Xpert VL-XC assay was comparable to the reference assays for detecting HIV infection in these cases. The Xpert Qual-XC assay was less sensitive than plasma-based HIV RNA assays for detecting HIV in the setting of CAB-LA PrEP. IMPORTANCE: HIV RNA assays can detect HIV infections earlier than HIV rapid tests or Ag/Ab tests in persons using CAB-LA PrEP. Earlier HIV diagnosis could allow for earlier treatment initiation and reduced risk of INSTI resistance. POC tests may help detect HIV infection before CAB-LA administration and may be more accessible than laboratory-based assays in some settings. In this study, the POC Xpert VL-XC assay detected HIV RNA in most samples from individuals who received CAB-LA PrEP and had delayed detection of HIV infection with HIV rapid tests and an Ag/Ab test. The performance of this assay was similar to laboratory-based HIV RNA assays in this cohort. The POC Xpert Qual-XC assay detects both HIV RNA and DNA, with a higher viral load cutoff for RNA detection. This assay was negative for most lower viral load samples and did not offer an advantage for HIV screening in persons using CAB-LA PrEP.

4.
ACS Chem Neurosci ; 15(14): 2600-2611, 2024 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-38957957

RESUMO

Over a century has passed since Alois Alzheimer first described Alzheimer's disease (AD), and since then, researchers have made significant strides in understanding its pathology. One key feature of AD is the presence of amyloid-ß (Aß) peptides, which form amyloid plaques, and therefore, it is a primary target for treatment studies. Naturally occurring peptides have garnered attention for their potential pharmacological benefits, particularly in the central nervous system. In this study, nine peptide derivatives of Crotamine, a polypeptide from Crotalus durissus terrificus Rattlesnake venom, as well as one d-enantiomer, were evaluated for their ability to modulate Aß42 aggregation through various assays such as ThT, QIAD, SPR, and sFIDA. All tested peptides were able to decrease Aß42 aggregation and eliminate Aß42 aggregates. Additionally, all of the peptides showed an affinity for Aß42. This study is the first to describe the potential of crotamine derivative peptides against Aß42 aggregation and to identify a promising d-peptide that could be used as an effective pharmacological tool against AD in the future.


Assuntos
Peptídeos beta-Amiloides , Venenos de Crotalídeos , Fragmentos de Peptídeos , Peptídeos beta-Amiloides/metabolismo , Humanos , Animais , Agregados Proteicos/efeitos dos fármacos , Venenos de Serpentes/química , Peptídeos/farmacologia , Peptídeos/química , Crotalus
5.
Adv Drug Deliv Rev ; 211: 115347, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38844005

RESUMO

Extracellular Matrix (ECM) scaffolds and biomaterials have been widely used for decades across a variety of diverse clinical applications and have been implanted in millions of patients worldwide. ECM-based biomaterials have been especially successful in soft tissue repair applications but their utility in other clinical applications such as for regeneration of bone or neural tissue is less well understood. The beneficial healing outcome with the use of ECM biomaterials is the result of their biocompatibility, their biophysical properties and their ability to modify cell behavior after injury. As a consequence of successful clinical outcomes, there has been motivation for the development of next-generation formulations of ECM materials ranging from hydrogels, bioinks, powders, to whole organ or tissue scaffolds. The continued development of novel ECM formulations as well as active research interest in these materials ensures a wealth of possibilities for future clinical translation and innovation in regenerative medicine. The clinical translation of next generation formulations ECM scaffolds faces predictable challenges such as manufacturing, manageable regulatory pathways, surgical implantation, and the cost required to address these challenges. The current status of ECM-based biomaterials, including clinical translation, novel formulations and therapies currently under development, and the challenges that limit clinical translation of ECM biomaterials are reviewed herein.


Assuntos
Materiais Biocompatíveis , Matriz Extracelular , Medicina Regenerativa , Alicerces Teciduais , Humanos , Medicina Regenerativa/métodos , Materiais Biocompatíveis/química , Animais , Engenharia Tecidual/métodos , Pesquisa Translacional Biomédica
6.
J Biomech Eng ; 146(10)2024 10 01.
Artigo em Inglês | MEDLINE | ID: mdl-38709496

RESUMO

Thermodynamics is a fundamental topic of continuum mechanics and biomechanics, with a wide range of applications to physiological and biological processes. This study addresses two fundamental limitations of current thermodynamic treatments. First, thermodynamics tables distributed online by the U.S. National Institute of Standards and Technology (NIST) report properties of fluids as a function of absolute temperature T and absolute pressure P. These properties include mass density ρ, specific internal energy u, enthalpy h=u+P/ρ, and entropy s. However, formulations of jump conditions across phase boundaries derived from Newton's second law of motion and the first law of thermodynamics employ the gauge pressure p=P-Pr, where Pr is an arbitrarily selected referential absolute pressure. Interchanging p with P is not innocuous as it alters tabulated NIST values for u while keeping h and s unchanged. Using p for functions of state and governing equations solves the problem with using NIST entries for the specific internal energy u in standard thermodynamics tables and analyses of phase transformation in continuum mechanics. Second, constitutive models for the free energy of fluids, such as water and air, are not typically provided in standard thermodynamics treatments. This study proposes a set of constitutive models and validates them against suitably modified NIST data.


Assuntos
Termodinâmica , Estados Unidos , Fenômenos Biomecânicos , Fenômenos Mecânicos , Mecânica
7.
J Sleep Res ; : e14252, 2024 May 29.
Artigo em Inglês | MEDLINE | ID: mdl-38811745

RESUMO

The world-wide prevalence of insomnia disorder reaches up to 10% of the adult population. Women are more often afflicted than men, and insomnia disorder is a risk factor for somatic and mental illness, especially depression and anxiety disorders. Persistent hyperarousals at the cognitive, emotional, cortical and/or physiological levels are central to most theories regarding the pathophysiology of insomnia. Of the defining features of insomnia disorder, the discrepancy between minor objective polysomnographic alterations of sleep continuity and substantive subjective impairment in insomnia disorder remains enigmatic. Microstructural alterations, especially in rapid eye movement sleep ("rapid eye movement sleep instability"), might explain this mismatch between subjective and objective findings. As rapid eye movement sleep represents the most highly aroused brain state during sleep, it might be particularly prone to fragmentation in individuals with persistent hyperarousal. In consequence, mentation during rapid eye movement sleep may be toned more as conscious-like wake experience, reflecting pre-sleep concerns. It is suggested that this instability of rapid eye movement sleep is involved in the mismatch between subjective and objective measures of sleep in insomnia disorder. Furthermore, as rapid eye movement sleep has been linked in previous works to emotional processing, rapid eye movement sleep instability could play a central role in the close association between insomnia and depressive and anxiety disorders.

8.
Antimicrob Agents Chemother ; : e0147523, 2024 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-38709006

RESUMO

Long-acting cabotegravir is approved for pre-exposure prophylaxis and combination HIV treatment, both initiated with optional short-term oral lead-in (OLI). We evaluated the impact of OLI on long-acting cabotegravir pharmacokinetics. Cabotegravir plasma concentrations were compared between HIV-positive participants initiating injections with (n = 278) or without (n = 110) OLI in phase III treatment study FLAIR and in HIV-negative participants using OLI (n = 263) in pivotal pre-exposure prophylaxis studies HPTN 083 and HPTN 084. Cabotegravir pharmacokinetic profiles were simulated in three populations (assigned-male-at-birth, 50%-assigned-female-at-birth, and assigned-female-at-birth) under three scenarios: first injection given (A) 1 or (B) 3 days after final OLI dose (OLI-injection gap) or (C) without OLI. The PK objective was 80% of participants achieving 4× in vitro protein-adjusted 90% maximal inhibitory concentration (PA-IC90) and 50% achieving 8× PA-IC90. Observed trough concentrations (Cτ) were similar with and without OLI (P > 0.3). With a 3-day OLI-injection gap, simulated pre-injection Cτ remained above PK objective. Approximately 1-2 weeks after the first injection, simulated PK profiles became nearly identical among all scenarios. Without OLI, it was predicted that 80% of participants achieve 4× PA-IC90 in 1.2, 1.8, and 2.8 days after the first injection in each population, respectively, and 50% achieve 8× PA-IC90 in 1.4, 2.1, and 3.8 days, respectively. Observed long-acting cabotegravir exposure was similar with or without OLI, supporting optional OLI use. Cabotegravir exposure was predicted to remain above PK objective for OLI-injection gaps of ≤3 days and rapidly achieve PK objective after first injection without OLI. Findings are consistent between assigned-male-at-birth and assigned-female-at-birth populations.This study is registered with ClinicalTrials.gov as NCT02720094.

9.
J Int AIDS Soc ; 27(5): e26252, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38783534

RESUMO

INTRODUCTION: HPTN 083 demonstrated the superiority of long-acting cabotegravir (CAB-LA) versus daily oral emtricitabine/tenofovir disoproxil fumarate (TDF/FTC) as pre-exposure prophylaxis (PrEP) among cisgender men and transgender women who have sex with men (MSM/TGW). HPTN 083 provided the first opportunity to understand experiences with injectable PrEP in a clinical trial. METHODS: Participants from two US sites (Chicago, IL and Atlanta, GA) and one international site (Rio de Janeiro, Brazil) were purposively sampled for individual qualitative interviews (N = 40), between November 2019 and March 2020, to explore trial experiences, barriers to adherence and other factors that may have impacted study implementation or outcomes. The blinded phase ended early due to efficacy; this analysis includes interviews conducted prior to unblinding with three groups defined by adherence (i.e. injection visit attendance): adherent (n = 27), non-adherent (n = 12) and early discontinuers (n = 1). Data were organized using NVivo software and analysed using content analysis. RESULTS: Participants (mean age: 27) were primarily cisgender MSM (90%) and Black/African American (60%). Reasons for trial enrolment and PrEP use included a preference for using HIV prevention medication versus treatment in the event of HIV acquisition; the ability to enhance health via study-related education and services; access to a novel, convenient HIV prevention product at no cost; and contributing to MSM/TGW communities through research. Participants contrasted positive experiences with study staff with their routine clinical care, and emphasized increased scheduling flexibility, thorough communication, non-judgemental counselling and open, affirming environments (e.g. compassion, less stigma) as adherence facilitators. Injection experiences were positive overall; some described early injection-related anxiety, which abated with time and when given some measure of control (e.g. pre-injection countdown), and minimal injection site discomfort. Some concerns and misperceptions about injectable PrEP were reported. Barriers to adherence, across all adherence categories, included structural factors (e.g. financial constraints, travel) and competing demands (e.g. work schedules). CONCLUSIONS: Respondents viewed injectable PrEP trial participation as a positive experience and a means of enhancing wellbeing. Study site flexibility and affirming clinic environments, inclusive of non-judgemental counselling, were key facilitators of adherence. To support injection persistence, interventions that address structural barriers and promote flexible means of injection delivery may be most effective.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Adesão à Medicação , Profilaxia Pré-Exposição , Humanos , Masculino , Profilaxia Pré-Exposição/métodos , Adesão à Medicação/estatística & dados numéricos , Infecções por HIV/prevenção & controle , Infecções por HIV/tratamento farmacológico , Feminino , Fármacos Anti-HIV/administração & dosagem , Fármacos Anti-HIV/uso terapêutico , Adulto , Pessoas Transgênero/psicologia , Homossexualidade Masculina , Adulto Jovem , Piridonas/administração & dosagem , Piridonas/uso terapêutico , Brasil , Injeções , Piridinas/administração & dosagem , Piridinas/uso terapêutico , Entrevistas como Assunto , Tenofovir/administração & dosagem , Tenofovir/uso terapêutico , Combinação Emtricitabina e Fumarato de Tenofovir Desoproxila/administração & dosagem , Combinação Emtricitabina e Fumarato de Tenofovir Desoproxila/uso terapêutico , Pessoa de Meia-Idade , Dicetopiperazinas
10.
J Addict Dis ; : 1-4, 2024 May 31.
Artigo em Inglês | MEDLINE | ID: mdl-38821937

RESUMO

BACKGROUND: Persons with substance use disorders (SUDs) have a greater risk of suicide compared with the general population. Adjustment Disorder (AD) has been under-researched in SUD populations. OBJECTIVE(S): To characterize rates, and associated features, of AD among persons with SUD for whom lethality concerns arise in a general hospital setting. METHODS: Retrospective analysis of electronic medical record data from psychiatric consultations during a consecutive six-month period. RESULTS: Compared with persons with SUD classified as non-attempters, suicide attempters were significantly more likely to be diagnosed with AD. Multiple logistic regression models revealed patients with SUD referred for suicide-related concerns have an increased risk of suicide attempt if also diagnosed with AD or if they have a history of prior suicide attempt. CONCLUSIONS: These data are in line with the contention that SUD, with comorbid AD, portend significant risk for suicide. AD represents an important disorder to recognize and target in suicide prevention strategies.

11.
Am Surg ; : 31348241244634, 2024 Apr 04.
Artigo em Inglês | MEDLINE | ID: mdl-38576134

RESUMO

Diagnosis of ductal carcinoma in situ (DCIS) represents about 25% of newly diagnosed breast cancers. There is debate about the benefit of sentinel lymph node biopsy (SLNB) for further staging and guidance of therapy in patients with DCIS. Current guidelines recommend SLNB for patients undergoing breast-conserving therapy (BCT) for DCIS. Utilizing superparamagnetic iron oxide (SPIO) nanoparticles as a tracer may allow for a delayed SLNB (d-SLNB), typically within a month of injection. We present our experience with a patient who due to complications from surgery could not complete her d-SLNB for 165 days. The SPIO tracer remained active in the lymph node and remained clinically useful for this five and a half month gap from time of injection. Further study is needed to determine the clinical longevity of SPIO in a lymph node.

12.
Chem Sci ; 15(15): 5596-5603, 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38638211

RESUMO

Di-tert-butyldiphosphatetrahedrane (tBuCP)2 (1) is a mixed carbon- and phosphorus-based tetrahedral molecule, isolobal to white phosphorus (P4). However, despite the fundamental significance and well-explored reactivity of the latter molecule, the precise structure of the free (tBuCP)2 molecule (1) and a detailed analysis of its electronic properties have remained elusive. Here, single-crystal X-ray structure determination of 1 at low temperature confirms the tetrahedral structure. Furthermore, quantum chemical calculations confirm that 1 is isolobal to P4 and shows a strong largely isotropic diamagnetic response in the magnetic field and thus pronounced spherical aromaticity. A spectroscopic and computational study on the photochemical reactivity reveals that diphosphatetrahedrane 1 readily dimerises to the ladderane-type phosphaalkyne tetramer (tBuCP)4 (2) under irradiation with UV light. With sufficient thermal activation energy, the dimerisation proceeds also in the dark. In both cases, an isomerisation to a 1,2-diphosphacyclobutadiene 1' is the first step. This intermediate subsequently undergoes a [2 + 2] cycloaddition with a second 1,2-diphosphacyclobutadiene molecule to form 2. The 1,2-diphosphacyclobutadiene intermediate 1' can be trapped chemically by N-methylmaleimide as an alternative [2 + 2] cycloaddition partner.

13.
Clin Infect Dis ; 2024 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-38484128

RESUMO

BACKGROUND: Oral pre-exposure prophylaxis (PrEP) with emtricitabine/tenofovir disoproxil fumarate (F/TDF) has high efficacy against HIV-1 acquisition. Seventy-two prospective studies of daily oral F/TDF PrEP were conducted to evaluate HIV-1 incidence, drug resistance, adherence, and bone and renal safety in diverse settings. METHODS: HIV-1 incidence was calculated from incident HIV-1 diagnoses after PrEP initiation and within 60 days of discontinuation. Tenofovir concentration in dried blood spots (DBS), drug resistance, and bone/renal safety indicators were evaluated in a subset of studies. RESULTS: Among 17,274 participants, there were 101 cases with new HIV-1 diagnosis (0.77 per 100 person-years; 95% CI 0.63-0.94). In 78 cases with resistance data, 18 (23%) had M184I or V, one (1.3%) had K65R, and three (3.8%) had both mutations. In 54 cases with tenofovir concentration data from DBS, 45 (83.3%), 2 (3.7%), 6 (11.1%), and 1 (1.9%) had average adherence of <2, 2-3, 4-6, and ≥7 doses/week, respectively, and the corresponding incidence was 3.9 (95% CI 2.9-5.3), 0.24 (0.060-0.95), 0.27 (0.12-0.60), and 0.054 (0.008-0.38) per 100 person-years. Adherence was low in younger participants, Hispanic/Latinx and Black participants, cisgender women, and transgender women. Bone and renal adverse event incidence rates were 0.69 and 11.8 per 100 person-years, respectively, consistent with previous reports. CONCLUSIONS: Leveraging the largest pooled analysis of global PrEP studies to date, we demonstrate that F/TDF is safe and highly effective, even with less than daily dosing, in diverse clinical settings, geographies, populations, and routes of HIV-1 exposure.

14.
Cureus ; 16(1): e53314, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38435952

RESUMO

Left vagus nerve stimulation (VNS) is an advanced therapeutic option for refractory, drug-resistant epilepsy. A 45-year-old woman with a history of refractory catamenial focal epilepsy since age 16, treated with a five-drug antiepileptic regimen and VNS (implanted eight and one-half years prior), presented with dyspnea, chest discomfort, and lightheadedness. During observation, symptoms recurred and were associated with bradycardia (<20 bpm) and a complete atrioventricular node (AVN) block. Following admission, she continued to experience recurrent symptomatic AVN block and transient ventricular asystole, temporally correlated with her baseline seizure activity and resultant activation of her VNS. Deactivation of VNS resolved her bradyarrhythmia, and she experienced no recurrence over 14 months of follow-up. This case highlights a therapeutic dilemma in cases of refractory epilepsy, with limited therapeutic options if seizure activity requires VNS to be controlled.

15.
J Parkinsons Dis ; 14(3): 437-449, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38517806

RESUMO

Long-term exposure to pesticides used in agriculture is increasingly being identified as a risk factor for developing Parkinson's disease. How chronic pesticide exposure might contribute to the growth of Parkinson's disease in the mainly agricultural communities of Sub-Saharan Africa has thus far received limited attention. There are specific concerns in this area of the world: aging of the population, in combination with chronic exposure to widely used pesticides, including those that have been restricted elsewhere in the world because of neurotoxicity and other health risks. Of interest, the prevalence of Parkinson's disease among specific (semi)nomadic populations in Tanzania seems very low, possibly due to their lack of exposure to agricultural chemicals. But at the same time, pesticides have also brought important benefits to this part of the world. Specifically, in Sub-Saharan Africa, pesticides have been directly helpful in preventing and controlling famine and in containing major human infectious diseases. This creates a complex risk-benefit ratio to the use of pesticides within a global perspective, and urgently calls for the development and implementation of affordable alternatives for areas such as Sub-Saharan Africa, including non-neurotoxic compounds and non-chemical alternatives for the use of pesticides.


Assuntos
Doença de Parkinson , Praguicidas , Humanos , África Subsaariana/epidemiologia , Praguicidas/efeitos adversos , Doença de Parkinson/epidemiologia , Doença de Parkinson/etiologia , Exposição Ambiental/efeitos adversos , Fatores de Risco
16.
Int J Mol Sci ; 25(3)2024 Jan 24.
Artigo em Inglês | MEDLINE | ID: mdl-38338694

RESUMO

The arbovirus Chikungunya (CHIKV) is transmitted by Aedes mosquitoes in urban environments, and in humans, it triggers debilitating symptoms involving long-term complications, including arthritis and Guillain-Barré syndrome. The development of antiviral therapies is relevant, as no efficacious vaccine or drug has yet been approved for clinical application. As a detailed map of molecules underlying the viral infection can be obtained from the metabolome, we validated the metabolic signatures of Vero E6 cells prior to infection (CC), following CHIKV infection (CV) and also upon the inclusion of the nsP2 protease inhibitor wedelolactone (CWV), a coumestan which inhibits viral replication processes. The metabolome groups evidenced significant changes in the levels of lactate, myo-inositol, phosphocholine, glucose, betaine and a few specific amino acids. This study forms a preliminary basis for identifying metabolites through HR-MAS NMR (High Resolution Magic Angle Spinning Nuclear Magnetic Ressonance Spectroscopy) and proposing the affected metabolic pathways of cells following viral infection and upon incorporation of putative antiviral molecules.


Assuntos
Aedes , Febre de Chikungunya , Animais , Chlorocebus aethiops , Humanos , Células Vero , Metabolômica , Replicação Viral , Antivirais/farmacologia
17.
bioRxiv ; 2024 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-38260457

RESUMO

Neuroblastoma is a highly lethal childhood tumor derived from differentiation-arrested neural crest cells1,2. Like all cancers, its growth is fueled by metabolites obtained from either circulation or local biosynthesis3,4. Neuroblastomas depend on local polyamine biosynthesis, with the inhibitor difluoromethylornithine showing clinical activity5. Here we show that such inhibition can be augmented by dietary restriction of upstream amino acid substrates, leading to disruption of oncogenic protein translation, tumor differentiation, and profound survival gains in the TH-MYCN mouse model. Specifically, an arginine/proline-free diet decreases the polyamine precursor ornithine and augments tumor polyamine depletion by difluoromethylornithine. This polyamine depletion causes ribosome stalling, unexpectedly specifically at adenosine-ending codons. Such codons are selectively enriched in cell cycle genes and low in neuronal differentiation genes. Thus, impaired translation of these codons, induced by the diet-drug combination, favors a pro-differentiation proteome. These results suggest that the genes of specific cellular programs have evolved hallmark codon usage preferences that enable coherent translational rewiring in response to metabolic stresses, and that this process can be targeted to activate differentiation of pediatric cancers.

18.
Sleep Med Rev ; 73: 101878, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38056381

RESUMO

Insomnia disorder signifies a major public health concern. The development of neuroimaging techniques has permitted to investigate brain mechanisms at a structural and functional level. The present systematic review aims at shedding light on functional, structural, and metabolic substrates of insomnia disorder by integrating the available published neuroimaging data. The databases PubMed, PsycARTICLES, PsycINFO, CINAHL and Web of Science were searched for case-control studies comparing neuroimaging data from insomnia patients and healthy controls. 85 articles were judged as eligible. For every observed finding of each study, the effect size was calculated from standardised mean differences, statistic parameters and figures, showing a marked heterogeneity that precluded a comprehensive quantitative analysis. From a qualitative point of view, considering the findings of significant group differences in the reported regions across the articles, this review highlights the major involvement of the anterior cingulate cortex, thalamus, insula, precuneus and middle frontal gyrus, thus supporting some central themes in the debate on the neurobiology of and offering interesting insights into the psychophysiology of sleep in this disorder.


Assuntos
Neuroimagem , Distúrbios do Início e da Manutenção do Sono , Humanos , Encéfalo/diagnóstico por imagem , Giro do Cíngulo , Sono , Distúrbios do Início e da Manutenção do Sono/diagnóstico por imagem
19.
Clin Infect Dis ; 78(2): 402-410, 2024 02 17.
Artigo em Inglês | MEDLINE | ID: mdl-37823865

RESUMO

BACKGROUND: Adherence and retention concerns raise questions about the effectiveness and cost-effectiveness of oral HIV pre-exposure prophylaxis (PrEP) in young men who have sex with men (YMSM). METHODS: Using an adolescent-focused simulation model, we compared annual HIV screening alone with tenofovir disoproxil fumarate/emtricitabine-based oral PrEP with every 3-month HIV screening in YMSM (aged 15-24) at increased risk of HIV. Data derived from published sources included: age-stratified HIV incidence/100 person-years (PY) on- or off-PrEP (0.6-10.1 or 0.4-6.4), PrEP retention at 6 years (28%), transmissions by HIV RNA level (0.0-78.4/100PY) and annual costs of antiretroviral therapy ($32 000-69 000), HIV care ($3100-34 600), and PrEP program/generic drug ($900/360). Outcomes included transmissions (percent of cohort infected), quality-adjusted life-years (QALYs), costs ($), and incremental cost-effectiveness ratios ($/QALY). We explored the sensitivity of findings to variation in HIV incidence and drug prices. RESULTS: Compared with annual screening alone, PrEP would increase QALYs (9.58 to 9.67), reduce new infections (37% to 30%), and decrease costs (by $5000) over 10 years. PrEP would remain cost-saving for HIV incidence off-PrEP ≥5.1/100PY or annual PrEP price ≤$1200. Over a lifetime horizon, PrEP would be cost-saving for HIV incidence off-PrEP ≥1.0/100PY, across all retention assumptions examined. PrEP would not be cost-effective at HIV incidence ≤0.1/100PY, regardless of drug price, due to programmatic costs. CONCLUSIONS: In US YMSM at increased risk of HIV, generic oral PrEP and every-3-month screening would be cost-saving compared with annual screening alone, even with high discontinuation and low adherence, over a range of HIV incidences.


Assuntos
Fármacos Anti-HIV , Infecções por HIV , Profilaxia Pré-Exposição , Minorias Sexuais e de Gênero , Masculino , Adolescente , Humanos , Estados Unidos/epidemiologia , Homossexualidade Masculina , Fármacos Anti-HIV/uso terapêutico , Medicamentos Genéricos , Análise Custo-Benefício , Infecções por HIV/tratamento farmacológico , Infecções por HIV/epidemiologia , Infecções por HIV/prevenção & controle
20.
Am J Surg ; 227: 183-188, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37821293

RESUMO

BACKGROUND: In 2016, the SSO and ABIM released a Choosing Wisely® guideline stating SLNB can be safely omitted in women ≥70 with HR â€‹+ â€‹HER-invasive breast cancer. No study evaluating concordance of care with this guideline has been performed within a comprehensive cancer center. METHODS: From 2005 to 2020, there were 382 patients with cT1-2N0 invasive carcinoma ER+/PR+ and HER2-identified as having undergone SLNB. These patients were then separated into two groups; those in the pre-guideline concordance cohort (2005-2015) and those in the post-guideline concordance (2016-2020) cohort. Axillary management concordance was trended over time. RESULTS: 382 patients from 2005 to 2020 with HR â€‹+ â€‹HER- IBC were identified. No difference was seen in SLNB pre-versus post-guidelines (p â€‹= â€‹0.35). Increased concordance was noted as age increased (p â€‹= â€‹0.0068) and adjuvant radiation therapy exclusion (p â€‹< â€‹0.0001) post-guideline release. Concordance improved over the years post-guideline release (R2 â€‹= â€‹0.45). CONCLUSIONS: Surgical guideline adoption occurs over time but may also be affected by outside decisions and factors. Further study into patterns of guideline adoption may facilitate improving adherence to guidelines.


Assuntos
Neoplasias da Mama , Linfonodo Sentinela , Humanos , Feminino , Biópsia de Linfonodo Sentinela , Linfonodo Sentinela/patologia , Estadiamento de Neoplasias , Neoplasias da Mama/patologia , Excisão de Linfonodo , Axila/patologia , Linfonodos/patologia
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