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1.
Chem Biomed Imaging ; 2(3): 222-232, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38551011

RESUMO

The Dual Imaging and Diffraction (DIAD) beamline at Diamond Light Source (Didcot, U.K.) implements a correlative approach to the dynamic study of materials based on concurrent analysis of identical sample locations using complementary X-ray modalities to reveal structural detail at various length scales. Namely, the underlying beamline principle and its practical implementation allow the collocation of chosen regions within the sample and their interrogation using real-space imaging (radiography and tomography) and reciprocal space scattering (diffraction). The switching between the two principal modes is made smooth and rapid by design, so that the data collected is interlaced to obtain near-simultaneous multimodal characterization. Different specific photon energies are used for each mode, and the interlacing of acquisition steps allows conducting static and dynamic experiments. Building on the demonstrated realization of this state-of-the-art approach requires further refining of the experimental practice, namely, the methods for gauge volume collocation under different modes of beam-sample interaction. To address this challenge, experiments were conducted at DIAD devoted to the study of human dental enamel, a hierarchical structure composed of hydroxyapatite mineral nanocrystals, as a static sample previously affected by dental caries (tooth decay) as well as under dynamic conditions simulating the process of acid demineralization. Collocation and correlation were achieved between WAXS (wide-angle X-ray scattering), 2D (radiographic), and 3D (tomographic) imaging. While X-ray imaging in 2D or 3D modes reveals real-space details of the sample microstructure, X-ray scattering data for each gauge volume provided statistical nanoscale and ultrastructural polycrystal reciprocal-space information such as phase and preferred orientation (texture). Careful registration of the gauge volume positions recorded during the scans allowed direct covisualization of the data from two modalities. Diffraction gauge volumes were identified and visualized within the tomographic data sets, revealing the underlying local information to support the interpretation of the diffraction patterns. The present implementation of the 4D microscopy paradigm allowed following the progression of demineralization and its correlation with time-dependent WAXS pattern evolution in an approach that is transferable to other material systems.

2.
Chem Biomed Imaging ; 2(3): 213-221, 2024 Mar 25.
Artigo em Inglês | MEDLINE | ID: mdl-38551010

RESUMO

High-resolution spatial and temporal analysis and 3D visualization of time-dependent processes, such as human dental enamel acid demineralization, often present a challenging task. Overcoming this challenge often requires the development of special methods. Dental caries remains one of the most important oral diseases that involves the demineralization of hard dental tissues as a consequence of acid production by oral bacteria. Enamel has a hierarchically organized architecture that extends down to the nanostructural level and requires high resolution to study its evolution in detail. Enamel demineralization is a dynamic process that is best investigated with the help of in situ experiments. In previous studies, synchrotron tomography was applied to study the 3D enamel structure at certain time points (time-lapse tomography). Here, another distinct approach to time-evolving tomography studies is presented, whereby the sample image is reconstructed as it undergoes continuous rotation over a virtually unlimited angular range. The resulting (single) data set contains the data for multiple (potentially overlapping) intermediate tomograms that can be extracted and analyzed as desired using time-stepping selection of data subsets from the continuous fly-scan recording. One of the advantages of this approach is that it reduces the amount of time required to collect an equivalent number of single tomograms. Another advantage is that the nominal time step between successive reconstructions can be significantly reduced. We applied this approach to the study of acidic enamel demineralization and observed the progression of demineralization over time steps significantly smaller than the total acquisition time of a single tomogram, with a voxel size smaller than 0.5 µm. It is expected that the approach presented in this paper can be useful for high-resolution studies of other dynamic processes and for assessing small structural modifications in evolving hierarchical materials.

3.
J Addict Med ; 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38446860

RESUMO

OBJECTIVES: Smoking prevalence remains high among low-income smokers. Understanding processes (eg, withdrawal, craving, motivation) in early smoking cessation is crucially important for designing effective interventions for this population. METHODS: This is a secondary analysis of a novel, in-session sampling intervention (ie, In Vivo) as compared with standard care behavioral smoking cessation counseling (SC) among community-dwelling low-income smokers (n = 83). This analysis examined the effect of 5 in-session sampling interventions on cessation-related processes and perceived advantages or disadvantages of nicotine replacement therapy (NRT) products over time using daily diaries. RESULTS: The In Vivo treatment had an early positive impact in terms of decreasing withdrawal symptoms and cravings, and increasing perceived advantages to NRT, with moderate to large effect sizes. Results also showed that the treatment effectively reduced withdrawal symptoms and cravings in-session, with small-to-medium and medium-to-large effect sizes, respectively. In-session reduction of withdrawal symptoms and cravings did not occur for the SC group, with the exception of decreased withdrawal symptoms occurring during week 4. The In Vivo treatment did not impact quit goal, desire to quit, abstinence self-efficacy, perceived difficulty in quitting, motivational engagement, or perceived disadvantages to NRT. The In Vivo group reported less daily cigarette use relative to the SC group, in addition to reporting less cigarette use on days they reported greater combination NRT use. CONCLUSIONS: There is preliminary support for this In Vivo treatment over SC in reducing withdrawal, craving, and the number of cigarettes smoked per day, as well as promoting perceived advantages of NRT among low-income smokers.

4.
Mol Psychiatry ; 2024 Mar 07.
Artigo em Inglês | MEDLINE | ID: mdl-38454079

RESUMO

Further research is needed to help improve both the standard of care and the outcome for patients with treatment-resistant depression. A particularly critical evidence gap exists with respect to whether pharmacological or non-pharmacological augmentation is superior to antidepressant switch, or vice-versa. The objective of this study was to compare the effectiveness of augmentation with aripiprazole or repetitive transcranial magnetic stimulation versus switching to the antidepressant venlafaxine XR (or duloxetine for those not eligible to receive venlafaxine) for treatment-resistant depression. In this multi-site, 8-week, randomized, open-label study, 278 subjects (196 females and 82 males, mean age 45.6 years (SD 15.3)) with treatment-resistant depression were assigned in a 1:1:1 fashion to treatment with either of these three interventions; 235 subjects completed the study. 260 randomized subjects with at least one post-baseline Montgomery-Asberg Depression Rating (MADRS) assessment were included in the analysis. Repetitive transcranial magnetic stimulation (score change (standard error (se)) = -17.39 (1.3) (p = 0.015) but not aripiprazole augmentation (score change (se) = -14.9 (1.1) (p = 0.069) was superior to switch (score change (se) = -13.22 (1.1)) on the MADRS. Aripiprazole (mean change (se) = -37.79 (2.9) (p = 0.003) but not repetitive transcranial magnetic stimulation augmentation (mean change (se) = -42.96 (3.6) (p = 0.031) was superior to switch (mean change (se) = -34.45 (3.0)) on the symptoms of depression questionnaire. Repetitive transcranial magnetic stimulation augmentation was shown to be more effective than switching antidepressants in treatment-resistant depression on the study primary measure. In light of these findings, clinicians should consider repetitive transcranial magnetic stimulation augmentation early-on for treatment-resistant depression.Trial registration: ClinicalTrials.gov, NCT02977299.

5.
Psychiatry Res ; 330: 115585, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37935086

RESUMO

In 2020, esketamine received a supplemental indication as a therapy for major depression with suicidal ideation (MDSI), based on protocols enrolling hospitalized patients. Given the high risk of suicide following hospital discharge and the high relapse rates following discontinuation of esketamine, the optimal long-term treatment approach remains unclear. Cognitive behavioral therapy (CBT) is highly effective in relapse prevention and has been shown to prevent suicide attempts in high-risk populations. Here we describe the study protocol for the CBT-ENDURE trial: Cognitive Behavioral Therapy Following Esketamine for Major Depression and SUicidal Ideation for RElapse Prevention. Patients with depression (N = 100) who are admitted to hospital or are outpatients with clinically significant suicidal ideation will be enrolled in the study. All patients will receive esketamine (twice weekly for four weeks) and will be randomly assigned (1:1 ratio) to receive a 16-week course of CBT plus treatment as usual (CBT group) or treatment as usual only (TAU only group). Patients are followed for a total of 6 months. Supported under a funding announcement from NIMH to conduct safety and feasibility trials for patients at high risk for suicide, the primary outcome of the CBT-ENDURE study is feasibility (as measured by recruitment and retention), with a key secondary outcome being relapse among those who experience substantial benefit following two weeks of esketamine.


Assuntos
Terapia Cognitivo-Comportamental , Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/tratamento farmacológico , Ideação Suicida , Depressão/terapia , Terapia Cognitivo-Comportamental/métodos , Ensaios Clínicos Controlados Aleatórios como Assunto
6.
Front Psychiatry ; 14: 1221709, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-37840796

RESUMO

Background: The prevalence of depression and obesity among adolescents has markedly increased over the last few decades. A bidirectional relationship has been proposed between depression and obesity in adolescence, but it remains poorly understood. Inflammation is a phenomenon that has been implicated in both disorders. Thus, a cross-sectional study was designed to investigate inflammation as a factor in the association between obesity and depression. The goal of this study is to better understand the interplay between these two disorders. Methods: The study sample consisted of female and male, black and white adolescents aged 15-18 years. Participants were diagnosed with major depressive disorder (MDD) according to the Diagnostic and Statistical Manual of Mental Disorders-5. Depression severity was determined using the Quick Inventory of Depressive Symptomatology (QIDS). Participants completed the Childhood Trust Events Survey (CTES) and received an Early Life Stress (ELS) score based on the survey results. Those with a score of ≥4 were placed in the ELS group and those with a score ≤ 3 were placed in the non-ELS group. Anthropometric measures and a Dual Energy X-ray Absorptiometry (DEXA) scan were performed for body composition. Blood samples were collected to measure inflammatory factors. Results: Adolescents with MDD (n = 47) had significantly elevated body mass index (BMI) percentiles compared to the controls (n = 47) (77.11 ± 3.58 vs. 59.63 ± 4.40), and increased adiposity measures, including total fat (p = 0.016), trunk fat (p = 0.016), and trunk/total fat ratio (p = 0.021). Levels of C-reactive protein, tumor necrosis factor-alpha, interleukin-6, leptin, and adiponectin varied significantly between the MDD and control groups, however, significance was not retained when BMI percentile and ELS score were controlled. There was a significant and positive relationship between QIDS and multiple measures of adiposity such as BMI percentile, visceral abdominal tissue, and trunk/total ratio. Depression severity was best predicted by ELS score, visceral adipose tissue, and adiponectin level. Conclusion: Adolescents with MDD had increased levels of inflammatory factors and many measures of adiposity. Thus, the treatment of adolescent depression should include a focus on managing body composition and reducing chronic inflammation to potentially improve treatment outcomes.

7.
Mol Psychiatry ; 28(9): 3920-3929, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37735501

RESUMO

Major depressive disorder (MDD) is highly prevalent in adolescents and is a major risk factor for suicidality. Recent evidence shows that accelerated cellular senescence/aging is associated with psychiatric illness, including depression, in adults. The present study examined if the relationships of telomere length (TL) and mitochondrial DNA copy number (mtDNAcn), two critical indicators of cellular senescence/aging, are altered in depressed adolescents and whether these alterations are associated with suicidality, early-life adversities, and other co-occuring factors. In genomic DNA isolated from 53 adolescents (ages 16-19, 19 MDD with suicide attempt/suicidal ideation [MDD + SI/SA], 14 MDD without SA/SI [MDD-SI/SA], and 20 healthy controls [HC]), TL and mtDNAcn were measured as the ratio between the number of telomere repeats and that of a single-copy nuclear-hemoglobin [HBG] gene or the amount of mtDNA (NADH dehydrogenase, subunit 1) relative to HBG. Our data show that TL was significantly lower, and mtDNAcn was significantly higher in the total MDD group than HC. TL was significantly lower and mtDNAcn was significantly higher in the MDD + SA/SI group than in the HC, whereas there were no differences in the MDD-SI/SA group. TL was positively correlated with mtDNAcn in both HC and MDD-SA/SI groups; however, TL was negatively correlated with mtDNAcn in MDD + SA/SI. Furthermore, TL was negatively correlated with the severity of both depression and anxiety, while mtDNAcn was positively correlated with the severity of prior emotional abuse. Our study indicates that cellular senescence is more advanced in depressed adolescents with suicidal ideation and that childhood emotional abuse may participate in such a process.


Assuntos
Transtorno Depressivo Maior , Suicídio , Adulto , Humanos , Adolescente , Criança , Ideação Suicida , Transtorno Depressivo Maior/genética , Variações do Número de Cópias de DNA/genética , DNA Mitocondrial/genética , Telômero/genética
8.
World Psychiatry ; 22(3): 394-412, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37713549

RESUMO

Treatment-resistant depression (TRD) is common and associated with multiple serious public health implications. A consensus definition of TRD with demonstrated predictive utility in terms of clinical decision-making and health outcomes does not currently exist. Instead, a plethora of definitions have been proposed, which vary significantly in their conceptual framework. The absence of a consensus definition hampers precise estimates of the prevalence of TRD, and also belies efforts to identify risk factors, prevention opportunities, and effective interventions. In addition, it results in heterogeneity in clinical practice decision-making, adversely affecting quality of care. The US Food and Drug Administration (FDA) and the European Medicines Agency (EMA) have adopted the most used definition of TRD (i.e., inadequate response to a minimum of two antidepressants despite adequacy of the treatment trial and adherence to treatment). It is currently estimated that at least 30% of persons with depression meet this definition. A significant percentage of persons with TRD are actually pseudo-resistant (e.g., due to inadequacy of treatment trials or non-adherence to treatment). Although multiple sociodemographic, clinical, treatment and contextual factors are known to negatively moderate response in persons with depression, very few factors are regarded as predictive of non-response across multiple modalities of treatment. Intravenous ketamine and intranasal esketamine (co-administered with an antidepressant) are established as efficacious in the management of TRD. Some second-generation antipsychotics (e.g., aripiprazole, brexpiprazole, cariprazine, quetiapine XR) are proven effective as adjunctive treatments to antidepressants in partial responders, but only the olanzapine-fluoxetine combination has been studied in FDA-defined TRD. Repetitive transcranial magnetic stimulation (TMS) is established as effective and FDA-approved for individuals with TRD, with accelerated theta-burst TMS also recently showing efficacy. Electroconvulsive therapy is regarded as an effective acute and maintenance intervention in TRD, with preliminary evidence suggesting non-inferiority to acute intravenous ketamine. Evidence for extending antidepressant trial, medication switching and combining antidepressants is mixed. Manual-based psychotherapies are not established as efficacious on their own in TRD, but offer significant symptomatic relief when added to conventional antidepressants. Digital therapeutics are under study and represent a potential future clinical vista in this population.

9.
Sci Rep ; 13(1): 14472, 2023 09 02.
Artigo em Inglês | MEDLINE | ID: mdl-37660110

RESUMO

Ascorbic acid (Asc), dexamethasone (Dex) and ß-glycerophosphate (ß-Gly) are commonly used to promote osteogenic behaviour by osteoblasts in vitro. According to the literature, several osteosarcoma cells lines appear to respond differently to the latter with regards to proliferation kinetics and osteogenic gene transcription. Unsurprisingly, these differences lead to contrasting data between publications that necessitate preliminary studies to confirm the phenotype of the chosen osteosarcoma cell line in the presence of Asc, Dex and ß-Gly. The present study exposed Saos-2 cells to different combinations of Asc, Dex and ß-Gly for 14 days and compared the response with immortalised human mesenchymal stromal/stem cells (MSCs). Cell numbers, cytotoxicity, mineralised matrix deposition and cell proliferation were analysed to assess osteoblast-like behaviour in the presence of Asc, Dex and ß-Gly. Additionally, gene expression of runt-related transcription factor 2 (RUNX2); osteocalcin (OCN); alkaline phosphatase (ALP); phosphate regulating endopeptidase homolog X-linked (PHEX); marker of proliferation MKI67 and proliferating cell nuclear antigen (PCNA) was performed every two days during the 14-day cultures. It was found that proliferation of Saos-2 cells was significantly decreased by the presence of ß-Gly which contrasted with hMSCs where no change was observed. Furthermore, unlike hMSCs, Saos-2 cells demonstrated an upregulated expression of late osteoblastic markers, OCN and PHEX that suggested ß-Gly could affect later stages of osteogenic differentiation. In summary, it is important to consider that ß-Gly significantly affects key cell processes of Saos-2 when using it as an osteoblast-like cell model.


Assuntos
Genes cdc , Osteogênese , Humanos , Glicerofosfatos/farmacologia , Linhagem Celular
10.
Int J Bipolar Disord ; 11(1): 28, 2023 Aug 13.
Artigo em Inglês | MEDLINE | ID: mdl-37573534

RESUMO

BACKGROUND: We tested the hypothesis that, after initial improvement with intravenous ketamine in patients with bipolar disorder (BD) with severe depression and acute suicidal thinking or behavior, a fixed-dose combination of oral D-cycloserine (DCS) and lurasidone (NRX-101) can maintain improvement more effectively than lurasidone alone. METHODS: This was a multi-center, double-blind, twostage, parallel randomized trial. Adult BD patients with depression and suicidal ideation or behavior were infused with ketamine or saline (Stage 1); those who improved were randomized to a fixed-dose combination of DCS and lurasidone vs. lurasidone alone (Stage 2) to maintain the improvement achieved in Stage 1. Depression was measured by the Montgomery Åsberg Depression Rating Scale (MADRS), and suicidal thinking and behavior was measured by the Columbia Suicide Severity Rating Scale (C-SSRS); global improvement was measured by the clinical global severity scale (CGI-S). CLINICALTRIALS: gov NCT02974010; Registered: November 22, 2016. RESULTS: Thirty-seven patients were screened and 22 were enrolled, randomized, and treated. All 22 patients treated in Stage 1 (17 with ketamine and 5 with saline) were enrolled into Stage 2, and 11 completed the study. The fixed-dose combination of DCS and lurasidone was significantly more effective than lurasidone alone in maintaining improvement in depression (MADRS LMS Δ-7.7; p = 0.03) and reducing suicidal ideation, as measured by C-SSRS (Δ-1.5; p = 0.02) and by CGI-SS (Δ-2.9; p = 0.03), and with a non-statistically significant decrease in depressive relapse (0% vs. 40%; p = 0.07). This sequential treatment regimen did not cause any significant safety events and demonstrated improvements in patient-reported side effects. CONCLUSIONS: Sequential treatment of a single infusion of ketamine followed by NRX-101 maintenance is a promising therapeutic approach for reducing depression and suicidal ideation in patients with bipolar depression who require hospitalization due to acute suicidal ideation and behavior. On the basis of these findings, Breakthrough Therapy Designation was awarded, and a Special Protocol Agreement was granted by the FDA for a registrational trial.

11.
ACS Appl Mater Interfaces ; 15(31): 37259-37273, 2023 Aug 09.
Artigo em Inglês | MEDLINE | ID: mdl-37524079

RESUMO

Caries, a major global disease associated with dental enamel demineralization, remains insufficiently understood to devise effective prevention or minimally invasive treatment. Understanding the ultrastructural changes in enamel is hampered by a lack of nanoscale characterization of the chemical spatial distributions within the dental tissue. This leads to the requirement to develop techniques based on various characterization methods. The purpose of the present study is to demonstrate the strength of analytic methods using a correlative technique on a single sample of human dental enamel as a specific case study to test the accuracy of techniques to compare regions in enamel. The science of the different techniques is integrated to genuinely study the enamel. The hierarchical structures within carious tissue were mapped using the combination of focused ion beam scanning electron microscopy with synchrotron X-ray tomography. The chemical changes were studied using scanning X-ray fluorescence (XRF) and X-ray wide-angle and small-angle scattering using a beam size below 80 nm for ångström and nanometer length scales. The analysis of XRF intensity gradients revealed subtle variations of Ca intensity in carious samples in comparison with those of normal mature enamel. In addition, the pathways for enamel rod demineralization were studied using X-ray ptychography. The results show the chemical and structural modification in carious enamel with differing locations. These results reinforce the need for multi-modal approaches to nanoscale analysis in complex hierarchically structured materials to interpret the changes of materials. The approach establishes a meticulous correlative characterization platform for the analysis of biomineralized tissues at the nanoscale, which adds confidence in the interpretation of the results and time-saving imaging techniques. The protocol demonstrated here using the dental tissue sample can be applied to other samples for statistical study and the investigation of nanoscale structural changes. The information gathered from the combination of methods could not be obtained with traditional individual techniques.


Assuntos
Cárie Dentária , Esmalte Dentário , Humanos , Microscopia Eletrônica de Varredura , Espalhamento a Baixo Ângulo , Raios X , Microscopia Confocal , Esmalte Dentário/diagnóstico por imagem , Cárie Dentária/diagnóstico por imagem
12.
Drug Alcohol Depend ; 249: 110815, 2023 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-37336007

RESUMO

BACKGROUND: Despite the demonstrated value of opioid overdose education and naloxone distribution (OEND) programs, uptake and utilization remains low. Accessibility to OEND is limited and traditional programs may not reach many high-risk individuals. This study evaluated the effectiveness of online opioid overdose and naloxone administration education and the impact of naloxone possession. METHODS: Individuals with self-reported illicit use of opioids were recruited via Craigslist advertisements and completed all assessments and education online via REDCap. Participants watched a 20-minute video outlining signs of opioid overdose and how to administer naloxone. They were then randomized to either receive a naloxone kit or be given instructions on where to obtain a kit. Effectiveness of training was measured with pre- and post-training knowledge questionnaires. Naloxone kit possession, overdoses, opioid use frequency, and treatment interest were self-reported on monthly follow-up assessments. RESULTS: Mean knowledge scores significantly increased from 6.82/9.00 to 8.22 after training (t(194)=6.85, p <0.001, 95% CI[1.00, 1.81], Cohen's d=0.85). Difference in naloxone possession between randomized groups was significant with a large effect size (p <0.001, diff=0.60, 95% CI[0.47, 0.73]). A bidirectional relationship was found between naloxone possession and frequency of opioid use. Overdoses and treatment interest were similar across possession status. CONCLUSIONS: Overdose education is effective in online video format. Disparity in naloxone possession across groups indicates barriers to obtaining naloxone from pharmacies. Naloxone possession did not influence risky opioid use or treatment interest and its impact on frequency of use warrants further investigation. TRIAL REGISTRATION: Clinitaltrials.gov-NCT04303000.


Assuntos
Overdose de Drogas , Overdose de Opiáceos , Transtornos Relacionados ao Uso de Opioides , Humanos , Naloxona/uso terapêutico , Analgésicos Opioides/uso terapêutico , Overdose de Opiáceos/tratamento farmacológico , Transtornos Relacionados ao Uso de Opioides/tratamento farmacológico , Overdose de Drogas/tratamento farmacológico , Antagonistas de Entorpecentes/uso terapêutico
13.
Dent J (Basel) ; 11(5)2023 May 09.
Artigo em Inglês | MEDLINE | ID: mdl-37232781

RESUMO

Caries is a chronic disease that causes the alteration of the structure of dental tissues by acid dissolution (in enamel, dentine and cementum) and proteolytic degradation (dentine and cementum) and generates an important cost of care. There is a need to visualise and characterise the acid dissolution process on enamel due to its hierarchical structure leading to complex structural modifications. The process starts at the enamel surface and progresses into depth, which necessitates the study of the internal enamel structure. Artificial demineralisation is usually employed to simulate the process experimentally. In the present study, the demineralisation of human enamel was studied using surface analysis carried out with atomic force microscopy as well as 3D internal analysis using synchrotron X-ray tomography during acid exposure with repeated scans to generate a time-lapse visualisation sequence. Two-dimensional analysis from projections and virtual slices and 3D analysis of the enamel mass provided details of tissue changes at the level of the rods and inter-rod substance. In addition to the visualisation of structural modifications, the rate of dissolution was determined, which demonstrated the feasibility and usefulness of these techniques. The temporal analysis of enamel demineralisation is not limited to dissolution and can be applied to other experimental conditions for the analysis of treated enamel or remineralisation.

14.
Dent J (Basel) ; 11(4)2023 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-37185477

RESUMO

Hard dental tissues possess a complex hierarchical structure that is particularly evident in enamel, the most mineralised substance in the human body. Its complex and interlinked organisation at the Ångstrom (crystal lattice), nano-, micro-, and macro-scales is the result of evolutionary optimisation for mechanical and functional performance: hardness and stiffness, fracture toughness, thermal, and chemical resistance. Understanding the physical-chemical-structural relationships at each scale requires the application of appropriately sensitive and resolving probes. Synchrotron X-ray techniques offer the possibility to progress significantly beyond the capabilities of conventional laboratory instruments, i.e., X-ray diffractometers, and electron and atomic force microscopes. The last few decades have witnessed the accumulation of results obtained from X-ray scattering (diffraction), spectroscopy (including polarisation analysis), and imaging (including ptychography and tomography). The current article presents a multi-disciplinary review of nearly 40 years of discoveries and advancements, primarily pertaining to the study of enamel and its demineralisation (caries), but also linked to the investigations of other mineralised tissues such as dentine, bone, etc. The modelling approaches informed by these observations are also overviewed. The strategic aim of the present review was to identify and evaluate prospective avenues for analysing dental tissues and developing treatments and prophylaxis for improved dental health.

15.
Artigo em Inglês | MEDLINE | ID: mdl-37192264

RESUMO

Objective: To examine the potential of using l-methylfolate (LMF) as an adjunctive therapy for major depressive disorder (MDD) and assess its role in filling current treatment gaps for patients who are overweight/obese and have chronic inflammation.Data Sources: The PubMed database was searched using the key words l-methylfolate, adjunctive, and depression to identify studies published from January 2000 to April 2021.Study Selection: Identified studies included 2 randomized controlled trials (RCTs), an open-label extension of these RCTs, and a real-world prospective study. Post hoc analyses that explored subgroups and their response to LMF treatment, including patients who were overweight and had elevated inflammatory biomarkers, were also included.Results: These studies support the use of LMF as an adjunctive treatment in patients with MDD not responding to antidepressant monotherapy. The most effective dose tested was 15 mg/day. Treatment response was higher in individuals with a body mass index (BMI) ≥ 30 kg/m2 and elevated levels of inflammatory biomarkers. Inflammation is associated with increased production of proinflammatory cytokines, which interferes with the synthesis and turnover of monoamine neurotransmitters, thereby contributing to expression of depressive symptomatology. LMF may mitigate these effects by facilitating the synthesis of tetrahydrobiopterin (BH4), a critical coenzyme in neurotransmitter production. Furthermore, LMF does not cause adverse reactions commonly associated with other adjunctive MDD treatment agents (eg, atypical antipsychotics), such as weight gain, metabolic perturbations, and movement disorders.Conclusion: LMF is effective as an adjunctive treatment in MDD and may especially benefit patients with higher BMI and inflammation.


Assuntos
Transtorno Depressivo Maior , Humanos , Transtorno Depressivo Maior/tratamento farmacológico , Sobrepeso/tratamento farmacológico , Quimioterapia Combinada , Biomarcadores , Inflamação/tratamento farmacológico , Ensaios Clínicos Controlados Aleatórios como Assunto
16.
Contemp Clin Trials Commun ; 33: 101131, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-37091508

RESUMO

Drug overdose is the leading cause of accidental death in the United States, with over 70% of drug related fatalities resulting from the use of opioids. Federal agencies have responded to this crisis with various recommendations including enhancing harm reduction approaches such as training laypersons to administer naloxone through Opioid Overdose Education and Naloxone Distribution (OEND) programs. Several studies have demonstrated that OEND programs effectively reduce opioid overdose mortality and are both safe and cost-effective, however, they are typically implemented in urban areas as part of large medical center research programs, needle exchanges, or drug treatment programs. Individuals living in areas without these programs or services lack access to critical and life-saving OEND. The current study examined the acceptability and feasibility of online recruitment, online opioid overdose education, and remote distribution of naloxone kits. Persons who illicitly use opioids and are at risk for overdose were recruited through online media and completed an opioid use questionnaire. If interested in receiving opioid overdose and naloxone administration training, participants completed pre- and post-intervention knowledge questionnaires, engaged in audiovisual training, and were randomized to either receive a naloxone kit or be given information on where they could obtain one. Preliminary results indicate feasibility and acceptability as evidenced by strong recruitment and retention, as well as high participant satisfaction ratings. Successful implementation of remote OEND through this project supports future employment of similar remote programs to expand this critical harm reduction strategy to high-risk individuals in areas lacking traditional OEND programs. Trial Registration #: Clinitaltrials.gov- NCT04303000.

17.
Cancer Cell Int ; 23(1): 65, 2023 Apr 10.
Artigo em Inglês | MEDLINE | ID: mdl-37038210

RESUMO

Sphingosine-1-phosphate (S1P) is a lipid mediator and its binding to the S1P receptor 2 (S1PR2) is reported to regulate cytoskeletal organization. Epidermal growth factor (EGF) has been shown to induce migration and invasion in tumour cells. Since binding of S1P to S1PR2 and EGF to the EGF receptors exhibit some overlapping functionality, this study aimed to determine whether S1PR2 was involved in EGF-induced migration and invasion of oral squamous cell carcinoma (OSCC) lines and to identify any potential crosstalk between the two pathways. Migration was investigated using the scratch wound assay while invasion was studied using the transwell invasion and multicellular tumour spheroid (MCTS) assays. Activity of Rac1, a RhoGTPase, was measured using G-LISA (small GTPase activation assays) while S1P production was indirectly measured via the expression of sphingosine kinase (Sphk). S1PR2 inhibition with 10 µM JTE013 reduced EGF-induced migration, invasion and Rac1 activity, however, stimulation of S1PR2 with 10 µM CYM5478 did not enhance the effect of EGF on migration, invasion or Rac1 activity. The data demonstrated a crosstalk between EGF/EGFR and S1P/S1PR2 pathways at the metabolic level. S1PR2 was not involved in EGF production, but EGF promoted S1P production through the upregulation of Sphk1. In conclusion, OSCC lines could not migrate and invade without S1PR2 regulation, even with EGF stimulation. EGF also activated S1PR2 by stimulating S1P production via Sphk1. The potential for S1PR2 to control cellular motility may lead to promising treatments for OSCC patients and potentially prevent or reduce metastasis.

18.
Adv Neurobiol ; 30: 363-385, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36928858

RESUMO

The Human Genome Project mapped the 3 billion base pairs in the human genome, which ushered in a new generation of genomically focused treatment development. While this has been very successful in other areas, neuroscience has been largely devoid of such developments. This is in large part because there are very few neurological or mental health conditions that are related to single-gene variants. While developments in pharmacogenomics have been somewhat successful, the use of genetic information in practice has to do with drug metabolism and adverse reactions. Studies of drug metabolism related to genetic variations are an important part of drug development. However, outside of cancer biology, the actual translation of genomic information into novel therapies has been limited. Epigenetics, which relates in part to the effects of the environment on DNA, is a promising newer area of relevance to CNS disorders. The environment can induce chemical modifications of DNA (e.g., cytosine methylation), which can be induced by the environment and may represent either shorter- or longer-term changes. Given the importance of environmental influences on CNS disorders, epigenetics may identify important treatment targets in the future.


Assuntos
Epigênese Genética , Genômica , Humanos , Metilação de DNA
19.
Clin Oral Investig ; 27(5): 2407-2417, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36738319

RESUMO

OBJECTIVES: This study aims to assess the obturation efficacy of sealers placed with different techniques using microcomputed tomography (µCT) and assess the influence of µCT testing parameters on the obturation data obtained. MATERIALS AND METHODS: Incisors and mesial roots of lower molars with standardized root length were scanned using µCT, and one tooth of each type was 3D printed in acrylic. Two obturation techniques (warm vertical and single cone) and 4 sealer types (AH Plus, BioRoot RCS, Totalfill BC, and Bio-C Sealers) were assessed following storage in Hank's balanced salt solution for 3 and 6 months by assessing gap and void volume percentages on both natural and replica incisor and molar roots. The storage solution was analysed to assess calcium ion leaching. The influence of temperature, tooth positioning, and moisture content of the teeth while µCT scanning was also investigated. RESULTS: The obturation quality in the incisor group was the same using both natural teeth and replicas (p > 0.05). No changes in void volume were identified when comparing the same sealer using different obturation techniques. The premixed sealers used in single-cone obturation exhibited high void volume in the 3D printed replicas in the long term. The temperature, positioning, and moisture content of the teeth did not affect the outcome of µCT testing. CONCLUSIONS: BioRoot RCS, Totalfill BC, and Bio-C Sealers are suitable for obturation of both complex and simple root canal systems using different obturation techniques with BioRoot RCS exhibiting the highest calcium ion release. 3D printed acrylic teeth can be used to assess the obturation quality in uncomplicated root canal systems. µCT parameters had no significant effect on the µCT measurement. CLINICAL RELEVANCE: The single-cone obturation technique with hydraulic sealer is a simple technique that can be used for obturation of all root canal systems.


Assuntos
Materiais Restauradores do Canal Radicular , Resinas Epóxi , Cálcio , Microtomografia por Raio-X , Compostos de Cálcio , Teste de Materiais , Obturação do Canal Radicular/métodos , Silicatos , Cavidade Pulpar
20.
Pediatr Emerg Care ; 39(1): 6-12, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36413430

RESUMO

OBJECTIVE: The aim of the study was to evaluate the ability of a combinatorial pharmacogenomic test to predict medication blood levels and relative clinical improvements in a selected pediatric population. METHODS: This study enrolled patients between ages 3 to 18 years who presented to a pediatric emergency department with acute psychiatric, behavioral, or mental health crisis and/or concerns, and had previously been prescribed psychotropic medications. Patients received combinatorial pharmacogenomic testing with medications categorized according to gene-drug interactions (GDIs); medications with a GDI were considered "incongruent," and medications without a GDI were considered "congruent." Blood levels for escitalopram, fluoxetine, aripiprazole, and clonidine were evaluated according to level of GDI. Relative clinical improvements in response to the prescribed psychotropic medications were measured using a parent-rated Clinical Global Impression of Improvement (CGI-I) assessment, where lower scores corresponded with greater improvement. RESULTS: Of the 100 patients enrolled, 73% reported taking ≥1 incongruent medication. There was no significant difference in CGI-I scores between patients prescribed congruent versus incongruent medications (3.37 vs 3.68, P = 0.343). Among patients who presented for depression or suicidal ideation, those prescribed congruent medications had significantly lower CGI-I scores compared with those taking incongruent medications ( P = 0.036 for depression, P = 0.018 for suicidal ideation). There was a significant association between medication GDI and blood levels for aripiprazole (n = 15, P = 0.01) and escitalopram (n = 10, P = 0.01). CONCLUSIONS: Our preliminary findings suggest that combinatorial pharmacogenomic testing can predict medication blood levels and relative outcomes based on medication congruency in children presenting to an emergency department with acute psychiatric/behavioral crises. Additional studies will be needed to confirm these findings.


Assuntos
Escitalopram , Farmacogenética , Humanos , Criança , Pré-Escolar , Adolescente , Aripiprazol/uso terapêutico , Psicotrópicos/uso terapêutico , Serviço Hospitalar de Emergência
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