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1.
PLoS Comput Biol ; 20(2): e1011815, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38306397

RESUMO

Clinical imaging modalities are a mainstay of modern disease management, but the full utilization of imaging-based data remains elusive. Aortic disease is defined by anatomic scalars quantifying aortic size, even though aortic disease progression initiates complex shape changes. We present an imaging-based geometric descriptor, inspired by fundamental ideas from topology and soft-matter physics that captures dynamic shape evolution. The aorta is reduced to a two-dimensional mathematical surface in space whose geometry is fully characterized by the local principal curvatures. Disease causes deviation from the smooth bent cylindrical shape of normal aortas, leading to a family of highly heterogeneous surfaces of varying shapes and sizes. To deconvolute changes in shape from size, the shape is characterized using integrated Gaussian curvature or total curvature. The fluctuation in total curvature (δK) across aortic surfaces captures heterogeneous morphologic evolution by characterizing local shape changes. We discover that aortic morphology evolves with a power-law defined behavior with rapidly increasing δK forming the hallmark of aortic disease. Divergent δK is seen for highly diseased aortas indicative of impending topologic catastrophe or aortic rupture. We also show that aortic size (surface area or enclosed aortic volume) scales as a generalized cylinder for all shapes. Classification accuracy for predicting aortic disease state (normal, diseased with successful surgery, and diseased with failed surgical outcomes) is 92.8±1.7%. The analysis of δK can be applied on any three-dimensional geometric structure and thus may be extended to other clinical problems of characterizing disease through captured anatomic changes.


Assuntos
Aorta , Dissecção Aórtica , Humanos , Aorta/diagnóstico por imagem , Aorta/cirurgia , Dissecção Aórtica/diagnóstico por imagem , Dissecção Aórtica/cirurgia
2.
J Infect Dis ; 2024 Jul 24.
Artigo em Inglês | MEDLINE | ID: mdl-39046150

RESUMO

BACKGROUND: CD4 measurement is pivotal in the management of advanced HIV disease. VISITECT® CD4 Advanced Disease (AccuBio Limited, Alva, UK; VISITECT) is an instrument-free, point-of-care, semi-quantitative test allowing visual identification of a CD4 ≤200 cells/µl, or >200 cells/µl from finger-prick or venous blood. METHODS: As part of a diagnostic accuracy study of FUJIFILM SILVAMP TB LAM (clinicaltrials.gov: NCT04089423), people living with HIV of ≥18 years old were prospectively recruited in seven countries from outpatient departments if a tuberculosis symptom was present, and from inpatient departments. Participants provided venous blood for CD4 measurement using flow cytometry (reference standard) and finger-prick blood for VISITECT (index text), performed at point-of-care. Sensitivity, specificity, and positive and negative predictive values of VISITECT to determine a CD4 ≤200 cells/µl were evaluated. RESULTS: Among 1604 participants, the median flow cytometry CD4 was 367 (IQR 128-626) cells/µl and 521 (32.5%) had a CD4 ≤200 cells/µl. VISITECT sensitivity was 92.7% (483/521, 95% CI 90.1-94.7%) and specificity was 61.4% (665/1083, 95% CI 58.4-64.3%). For participants with a CD4 between 0-100, 101-200, 201-300, 301-500, and >500 cells/µl, VISITECT misclassified 4.5% (95% CI 2.5-7.2%), 12.5 (95% CI 8.0-18.2%), 74.1% (95% CI 67.0-80.5%), 48.0% (95% CI 42.5-53.6%), and 22.6% (95% CI 19.3-26.3%), respectively. CONCLUSIONS: VISITECT's sensitivity, but not specificity, met the World Health Organization's minimal sensitivity and specificity threshold of 80% for point-of-care CD4 tests. VISITECT's quality needs to be assessed and its accuracy optimized. VISITECT´s utility as CD4 triage test should be investigated.

3.
N Engl J Med ; 384(18): 1705-1718, 2021 05 06.
Artigo em Inglês | MEDLINE | ID: mdl-33951360

RESUMO

BACKGROUND: Rifapentine-based regimens have potent antimycobacterial activity that may allow for a shorter course in patients with drug-susceptible pulmonary tuberculosis. METHODS: In an open-label, phase 3, randomized, controlled trial involving persons with newly diagnosed pulmonary tuberculosis from 13 countries, we compared two 4-month rifapentine-based regimens with a standard 6-month regimen consisting of rifampin, isoniazid, pyrazinamide, and ethambutol (control) using a noninferiority margin of 6.6 percentage points. In one 4-month regimen, rifampin was replaced with rifapentine; in the other, rifampin was replaced with rifapentine and ethambutol with moxifloxacin. The primary efficacy outcome was survival free of tuberculosis at 12 months. RESULTS: Among 2516 participants who had undergone randomization, 2343 had a culture positive for Mycobacterium tuberculosis that was not resistant to isoniazid, rifampin, or fluoroquinolones (microbiologically eligible population; 768 in the control group, 791 in the rifapentine-moxifloxacin group, and 784 in the rifapentine group), of whom 194 were coinfected with human immunodeficiency virus and 1703 had cavitation on chest radiography. A total of 2234 participants could be assessed for the primary outcome (assessable population; 726 in the control group, 756 in the rifapentine-moxifloxacin group, and 752 in the rifapentine group). Rifapentine with moxifloxacin was noninferior to the control in the microbiologically eligible population (15.5% vs. 14.6% had an unfavorable outcome; difference, 1.0 percentage point; 95% confidence interval [CI], -2.6 to 4.5) and in the assessable population (11.6% vs. 9.6%; difference, 2.0 percentage points; 95% CI, -1.1 to 5.1). Noninferiority was shown in the secondary and sensitivity analyses. Rifapentine without moxifloxacin was not shown to be noninferior to the control in either population (17.7% vs. 14.6% with an unfavorable outcome in the microbiologically eligible population; difference, 3.0 percentage points [95% CI, -0.6 to 6.6]; and 14.2% vs. 9.6% in the assessable population; difference, 4.4 percentage points [95% CI, 1.2 to 7.7]). Adverse events of grade 3 or higher occurred during the on-treatment period in 19.3% of participants in the control group, 18.8% in the rifapentine-moxifloxacin group, and 14.3% in the rifapentine group. CONCLUSIONS: The efficacy of a 4-month rifapentine-based regimen containing moxifloxacin was noninferior to the standard 6-month regimen in the treatment of tuberculosis. (Funded by the Centers for Disease Control and Prevention and others; Study 31/A5349 ClinicalTrials.gov number, NCT02410772.).


Assuntos
Antibióticos Antituberculose/administração & dosagem , Antituberculosos/uso terapêutico , Moxifloxacina/administração & dosagem , Mycobacterium tuberculosis/isolamento & purificação , Rifampina/administração & dosagem , Tuberculose Pulmonar/tratamento farmacológico , Adolescente , Adulto , Antibióticos Antituberculose/efeitos adversos , Antituberculosos/efeitos adversos , Criança , Intervalos de Confiança , Esquema de Medicação , Quimioterapia Combinada , Feminino , Humanos , Masculino , Moxifloxacina/efeitos adversos , Rifampina/efeitos adversos , Adulto Jovem
4.
Nicotine Tob Res ; 26(Supplement_1): S27-S35, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38366340

RESUMO

OBJECTIVE: Social media platforms are promising to provide smoking cessation support. This study aimed to identify baseline factors associated with cigarette smoking abstinence among young adult smokers enrolled in a real-world social media-based smoking cessation program. AIMS AND METHODS: We analyzed data from young adult smokers (aged 18-30 years) participating in a publicly available Facebook-based smoking cessation program serving the San Francisco Bay Area. The analytic sample consisted of 248 participants who completed both the baseline and follow-up surveys at 3 months. Multivariable logistic regression analysis determined baseline factors significantly associated with self-reported 7-day cigarette smoking abstinence at 3 months. RESULTS: Participants were race/ethnically diverse, well-educated, and 47.6% reported LGB + sexual identity. Those who reported dual use of cigarettes and e-cigarettes in the past 30 days (vs. cigarette use only), current alcohol users (vs. non-users), and those aged 25-30 years (vs. 18-24 years) were significantly less likely to report 7-day abstinence at 3 months. Non-daily smokers (vs. daily smokers) and those with high desire to quit smoking (vs. low to moderate desire) were more likely to report abstinence. Results also showed reduction in the percentage of e-cigarette and other tobacco product use among participants. CONCLUSIONS: Social media interventions may be more effective for young adult non-daily smokers and those with high desire to quit smoking. Smoking cessation programs may help reduce use of other tobacco products among treatment-seeking smokers. Smoking cessation interventions for young adults need to explicitly address dual use of cigarettes and e-cigarettes and use of alcohol. IMPLICATIONS: Findings of this study highlight the need for future interventions to address dual use of cigarettes and e-cigarettes and use of alcohol to improve cigarette smoking abstinence outcomes. The reduction in the use of other tobacco products among program participants indicates that social media smoking cessation programs may exert a broader positive influence on overall tobacco consumption. The large number of LGB+ smokers participating in the program suggests social media is a promising cessation channel for this hard-to-reach group, warranting further study.


Assuntos
Fumar Cigarros , Sistemas Eletrônicos de Liberação de Nicotina , Abandono do Hábito de Fumar , Mídias Sociais , Humanos , Adulto Jovem , Abandono do Hábito de Fumar/métodos , Fumantes
5.
Scand J Public Health ; : 14034948241247612, 2024 Apr 28.
Artigo em Inglês | MEDLINE | ID: mdl-38679806

RESUMO

AIM: This study aimed to investigate awareness of having hypertension, diabetes and dyslipidaemia and their associated factors among US adults. METHODS: Data from the National Health and Nutrition Examination Survey, including 21,399 adults aged ⩾20 years (pregnant women excluded) collected between 2011 and 2018, were used. Blood pressure was measured using a Baumanometer calibrated mercury true gravity wall model sphygmomanometer. Serum total cholesterol levels were measured using enzymatic assays. The percentage of haemoglobin A1C (HbA1c), which reflects long-term blood glucose levels, was measured and used to identify diabetes. Participants self-reported whether they were told by a doctor that they have hypertension, dyslipidaemia and diabetes. Awareness was defined as alignment between objective and self-reported measures for having the conditions. Sampling weights and the Taylor series linearisation variance estimation method were used in the analyses. RESULTS: The findings showed that 64.06% of people with hypertension, 54.71% of those with dyslipidaemia and 78.40% of those with diabetes were aware of having the respective condition. Age, sex and health insurance were associated with awareness of having all three conditions, but marital status was not associated with any outcome. Weight status was associated with awareness of having hypertension and dyslipidaemia, whereas ethnicity was associated with awareness of having hypertension and diabetes. Relative family income was only associated with awareness of having hypertension. CONCLUSIONS: Large proportions of US adults with hypertension, dyslipidaemia and diabetes are not aware of having the conditions. Interventions targeting groups at higher risk of being unaware of these conditions are needed.

6.
Clin Infect Dis ; 76(11): 2000-2006, 2023 06 08.
Artigo em Inglês | MEDLINE | ID: mdl-36660850

RESUMO

BACKGROUND: Subclinical tuberculosis has been increasingly recognized as a separate state in the spectrum of the disease. However, evidence on the transmissibility of subclinical tuberculosis is still inconclusive. METHODS: We re-analyzed the data from the 2007 combined tuberculosis prevalence and tuberculin surveys in Vietnam. Poisson regression with robust standard errors was conducted to assess the effect of clinical presentation of individuals with tuberculosis in the household on tuberculin skin test (TST) positivity among children aged 6-14 years who participated in the tuberculin survey, adjusting for child's age, smear status of the index patient, and other covariates. RESULTS: In the multivariate analysis, we found significantly increased risks for TST positivity in children living with patients with clinical, smear-positive tuberculosis, compared with those living with individuals without tuberculosis (adjusted risk ratio [aRR]: 3.04; 95% confidence interval [CI]: 2.00-4.63) and with those living with patients with subclinical tuberculosis, adjusting for index smear status (aRR: 2.26; 95% CI: 1.03-4.96). Among children aged 6-10 years, those living with patients with clinical, smear-positive tuberculosis and those living with patients with subclinical, smear-positive tuberculosis had similarly increased risks of TST positivity compared with those living with individuals without tuberculosis (aRRs [95% CI] of 3.56 [1.91-6.62] and 3.11 [1.44-6.72], respectively). CONCLUSIONS: Our findings support the hypothesis that smear-positive subclinical tuberculosis contributes to Mycobacterium tuberculosis transmission. To eliminate tuberculosis in 2035, control strategies need to address subclinical presentations of the disease.


Assuntos
Mycobacterium tuberculosis , Tuberculose Pulmonar , Tuberculose , Criança , Humanos , Tuberculose Pulmonar/epidemiologia , Tuberculina , Fatores de Risco , Teste Tuberculínico , Tuberculose/epidemiologia , Inquéritos e Questionários
7.
Emerg Infect Dis ; 29(5): 967-976, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37081548

RESUMO

To assess sex disparities in tuberculosis in Vietnam, we conducted a nested, case-control study based on a 2017 tuberculosis prevalence survey. We defined the case group as all survey participants with laboratory-confirmed tuberculosis and the control group as a randomly selected group of participants with no tuberculosis. We used structural equation modeling to describe pathways from sex to tuberculosis according to an a priori conceptual framework. Our analysis included 1,319 participants, of whom 250 were case-patients. We found that sex was directly associated with tuberculosis prevalence (adjusted odds ratio for men compared with women 3.0 [95% CI 1.7-5.0]) and indirectly associated through other domains. The strong sex difference in tuberculosis prevalence is explained by a complex interplay of factors relating to behavioral and environmental risks, access to healthcare, and clinical manifestations. However, after controlling for all those factors, a direct sex effect remains that might be caused by biological factors.


Assuntos
Tuberculose , Humanos , Feminino , Masculino , Vietnã/epidemiologia , Estudos de Casos e Controles , Tuberculose/epidemiologia , Inquéritos e Questionários , Prevalência
8.
Funct Integr Genomics ; 23(3): 271, 2023 Aug 10.
Artigo em Inglês | MEDLINE | ID: mdl-37561192

RESUMO

Rice (Oryza sativa L.) is one of the most important dietary carbohydrate sources for half of the world's population. However, it is not well adapted to environmental stress conditions, necessitating to create new and improved varieties to help ensure sufficient rice production in the face of rising populations and shrinking arable land. Recently, the development of the CRISPR/Cas9 gene editing system has allowed researchers to study functional genomics and engineer new rice varieties with great efficiency compared to conventional methods. In this study, we investigate the involvement of OsGER4, a germin-like protein identified by a genome-wide association study that is associated with rice root development under a stress hormone jasmonic acids treatment. Analysis of the OsGER4 promoter region revealed a series of regulatory elements that connect this gene to ABA signaling and water stress response. Under heat stress, osger4 mutant lines produce a significantly lower crown root than wild-type Kitaake rice. The loss of OsGER4 also led to the reduction of lateral root development. Using the GUS promoter line, OsGER4 expression was detected in the epidermis of the crown root primordial, in the stele of the crown root, and subsequently in the primordial of the lateral root. Taken together, these results illustrated the involvement of OsGER4 in root development under heat stress by regulating auxin transport through plasmodesmata, under control by both ABA and auxin signaling.


Assuntos
Oryza , Oryza/metabolismo , Raízes de Plantas/metabolismo , Estudo de Associação Genômica Ampla , Proteínas de Plantas/genética , Proteínas de Plantas/metabolismo , Resposta ao Choque Térmico/genética , Ácidos Indolacéticos/metabolismo , Regulação da Expressão Gênica de Plantas
9.
Planta ; 257(3): 57, 2023 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-36795295

RESUMO

MAIN CONCLUSION: Induced mutations in the SC-uORF of the tomato transcription factor gene SlbZIP1 by the CRISPR/Cas9 system led to the high accumulation of sugar and amino acid contents in tomato fruits. Tomato (Solanum lycopersicum) is one of the most popular and consumed vegetable crops in the world. Among important traits for tomato improvement such as yield, biotic and abiotic resistances, appearance, post-harvest shelf life and fruit quality, the last one seems to face more challenges because of its genetic and biochemical complexities. In this study, a dual-gRNAs CRISPR/Cas9 system was developed to induce targeted mutations in uORF regions of the SlbZIP1, a gene involved in the sucrose-induced repression of translation (SIRT) mechanism. Different induced mutations in the SlbZIP1-uORF region were identified at the T0 generation, stably transferred to the offspring, and no mutation was found at potential off-target sites. The induced mutations in the SlbZIP1-uORF region affected the transcription of SlbZIP1 and related genes in sugar and amino acid biosynthesis. Fruit component analysis showed significant increases in soluble solid, sugar and total amino acid contents in all SlbZIP1-uORF mutant lines. The accumulation of sour-tasting amino acids, including aspartic and glutamic acids, raised from 77 to 144%, while the accumulation of sweet-tasting amino acids such as alanine, glycine, proline, serine, and threonine increased from 14 to 107% in the mutant plants. Importantly, the potential SlbZIP1-uORF mutant lines with desirable fruit traits and no impaired effect on plant phenotype, growth and development were identified under the growth chamber condition. Our result indicates the potential utility of the CRISPR/Cas9 system for fruit quality improvement in tomato and other important crops.


Assuntos
Solanum lycopersicum , Fatores de Transcrição , Fatores de Transcrição/genética , Aminoácidos/metabolismo , Açúcares/metabolismo , Solanum lycopersicum/genética , Sistemas CRISPR-Cas , Frutas/genética , Frutas/metabolismo
10.
Nat Chem Biol ; 17(8): 915-923, 2021 08.
Artigo em Inglês | MEDLINE | ID: mdl-33958793

RESUMO

Plant-based photosensors, such as the light-oxygen-voltage sensing domain 2 (LOV2) from oat phototropin 1, can be modularly wired into cell signaling networks to remotely control protein activity and physiological processes. However, the applicability of LOV2 is hampered by the limited choice of available caging surfaces and its preference to accommodate the effector domains downstream of the C-terminal Jα helix. Here, we engineered a set of LOV2 circular permutants (cpLOV2) with additional caging capabilities, thereby expanding the repertoire of genetically encoded photoswitches to accelerate the design of optogenetic devices. We demonstrate the use of cpLOV2-based optogenetic tools to reversibly gate ion channels, antagonize CRISPR-Cas9-mediated genome engineering, control protein subcellular localization, reprogram transcriptional outputs, elicit cell suicide and generate photoactivatable chimeric antigen receptor T cells for inducible tumor cell killing. Our approach is widely applicable for engineering other photoreceptors to meet the growing need of optogenetic tools tailored for biomedical and biotechnological applications.


Assuntos
Proteínas de Arabidopsis/genética , Proteínas de Ligação a DNA/genética , Engenharia Genética , Optogenética , Animais , Proteínas de Arabidopsis/química , Proteínas de Arabidopsis/metabolismo , Células Cultivadas , Proteínas de Ligação a DNA/química , Proteínas de Ligação a DNA/metabolismo , Feminino , Humanos , Camundongos , Camundongos Endogâmicos NOD , Camundongos Transgênicos , Processos Fotoquímicos
11.
Soft Matter ; 19(47): 9206-9214, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37997177

RESUMO

While buckling is a time independent phenomenon for filaments or films bonded to soft elastic substrates, time evolution plays an important role when the substrate is a viscous fluid. Here we show that buckling instabilities in fluid-structure interactions can be reduced to the analysis of a growth function that amplifies the initial noise characterizing experimental or numerical error. The convolution between a specific growth function and noise leads to natural imperfections that emerge in the form of wave packets with a large scale modulation that can transform into localized structures depending on nonlinear effects. Specifically, we provide an experimental example where these wave packets are amplified into ridges for sufficiently low compression rates or are diluted into wrinkles for high compression rates.

12.
J Biomed Inform ; 145: 104460, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-37532000

RESUMO

While a large number of knowledge graphs have previously been developed by automatically extracting and structuring knowledge from literature, there is currently no such knowledge graph that encodes relationships between food, biochemicals and mental illnesses, even though a large amount of knowledge about these relationships is available in the form of unstructured text in biomedical literature articles. To address this limitation, this article describes the development of GENA - (Graph of mEntal-health and Nutrition Association), a knowledge graph that represents relations between nutrition and mental health, extracted from biomedical abstracts. GENA is constructed from PubMed abstracts that contain keywords relating to chemicals, food, and health. A hybrid named entity recognition (NER) model is firstly applied to these abstracts to identify various entities of interest. Subsequently, a deep syntax-based relation extraction model is used to detect binary relations between the identified entities. Finally, the resulting relations are used to populate the GENA knowledge graph, whose relationships can be accessed in an intuitive and interpretable manner using the Neo4J Database Management System. To evaluate the reliability of GENA, two annotators manually assessed a subset of the extracted relations. The evaluation results show that our methods obtain high precision for the NER task and acceptable precision and relative recall for the relation extraction task. GENA consists of 43,367 relationships that encode information about nutrition and health, of which 94.04% are new relations that are not present in existing ontologies of food and diseases. GENA is constructed based on scientific principles, and has the potential to be used within further applications to contribute towards scientific research within the domain. It is a pioneering knowledge graph in nutrition and mental health, containing a diverse range of relationship types. All of our source code and results are publicly available at https://github.com/ddlinh/gena-db.


Assuntos
Saúde Mental , Reconhecimento Automatizado de Padrão , Reprodutibilidade dos Testes , Software , PubMed
13.
J Biomed Inform ; 141: 104347, 2023 05.
Artigo em Inglês | MEDLINE | ID: mdl-37030658

RESUMO

Automatic extraction of patient medication histories from free-text clinical notes can increase the amount of relevant information to clinicians for developing treatment plans. In addition to detecting medication events, clinical text mining systems must also be able to predict event context, such as negation, uncertainty, and time of occurrence, in order to construct accurate patient timelines. Towards this goal, we introduce Levitated Context Markers (LCMs), a novel transformer-based model for contextualized event extraction. LCMs are an adaptation of levitated markers -originally developed for relation extraction- that allow pretrained transformer models to utilize global input representations while also focusing on event-related subspans using a sparse attention mechanism. In addition to outperforming a strong baseline model on the Contextualized Medication Event Dataset, we show that LCMs' sparse attention can provide interpretable predictions by detecting relevant context cues in an unsupervised manner.


Assuntos
Mineração de Dados , Registros , Humanos , Processamento de Linguagem Natural
14.
Tob Control ; 2023 Apr 18.
Artigo em Inglês | MEDLINE | ID: mdl-37072166

RESUMO

OBJECTIVE: To describe how young adults use electronic cigarettes (electronic nicotine delivery systems (ENDS)) for smoking cessation and reasons why they may or may not successfully quit smoking. METHODS: Longitudinal qualitative data were collected annually from 2017 to 2019 for 25 young adult tobacco users (aged 18-29 years) in California (USA) who used ENDS to quit/reduce smoking. Thematic and trajectory analyses were used to identify key within-person and between-person changes in tobacco/nicotine use over time. RESULTS: Five types of tobacco use transition were identified among baseline dual users of cigarettes and ENDS: sustained dual use without reduced smoking (n=8), transition to exclusive daily ENDS use (n=6), sustained dual use with reduced smoking (n=5), transition back to exclusive smoking (n=4) and transition to neither smoking nor vaping (n=2). Participants' ENDS use behaviour varied over time in terms of vaping quantity and device characteristics (eg, changing nicotine concentrations/flavours, switching between multiple devices). Three themes that related to successfully replacing cigarettes with ENDS were perceived positive physical effects, perceived satisfaction and enjoyment and context changes. Four themes for unsuccessful replacement were perceived negative physical discomforts, perceived addictiveness and harm, unsatisfactory substitution for cigarettes and device malfunction. CONCLUSIONS: Young adults' experiences with using ENDS as a smoking cessation aid were highly variable. Adequate nicotine delivery and perceived safety and benefits contributed to successfully reducing or quitting cigarettes. Providing behavioural counselling and standardising ENDS products may enhance cessation for young adults.

15.
J Chem Phys ; 158(11): 114904, 2023 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-36948817

RESUMO

DNA toroids are compact torus-shaped bundles formed by one or multiple DNA molecules being condensed from the solution due to various condensing agents. It has been shown that the DNA toroidal bundles are twisted. However, the global conformations of DNA inside these bundles are still not well understood. In this study, we investigate this issue by solving different models for the toroidal bundles and performing replica-exchange molecular dynamics (REMD) simulations for self-attractive stiff polymers of various chain lengths. We find that a moderate degree of twisting is energetically favorable for toroidal bundles, yielding optimal configurations of lower energies than for other bundles corresponding to spool-like and constant radius of curvature arrangements. The REMD simulations show that the ground states of the stiff polymers are twisted toroidal bundles with the average twist degrees close to those predicted by the theoretical model. Constant-temperature simulations show that twisted toroidal bundles can be formed through successive processes of nucleation, growth, quick tightening, and slow tightening of the toroid, with the two last processes facilitating the polymer threading through the toroid's hole. A relatively long chain of 512 beads has an increased dynamical difficulty to access the twisted bundle states due to the polymer's topological constraint. Interestingly, we also observed significantly twisted toroidal bundles with a sharp U-shaped region in the polymer conformation. It is suggested that this U-shaped region makes the formation of twisted bundles easier by effectively reducing the polymer length. This effect can be equivalent to having multiple chains in the toroid.


Assuntos
DNA , Simulação de Dinâmica Molecular , Conformação de Ácido Nucleico , Polímeros
16.
BMC Public Health ; 23(1): 945, 2023 05 25.
Artigo em Inglês | MEDLINE | ID: mdl-37231468

RESUMO

BACKGROUND: There is extensive evidence for the cost-effectiveness of programmatic and additional tuberculosis (TB) interventions, but no studies have employed the social return on investment (SROI) methodology. We conducted a SROI analysis to measure the benefits of a community health worker (CHW) model for active TB case finding and patient-centered care. METHODS: This mixed-method study took place alongside a TB intervention implemented in Ho Chi Minh City, Viet Nam, between October-2017 - September-2019. The valuation encompassed beneficiary, health system and societal perspectives over a 5-year time-horizon. We conducted a rapid literature review, two focus group discussions and 14 in-depth interviews to identify and validate pertinent stakeholders and material value drivers. We compiled quantitative data from the TB program's and the intervention's surveillance systems, ecological databases, scientific publications, project accounts and 11 beneficiary surveys. We mapped, quantified and monetized value drivers to derive a crude financial benefit, which was adjusted for four counterfactuals. We calculated a SROI based on the net present value (NPV) of benefits and investments using a discounted cash flow model with a discount rate of 3.5%. A scenario analysis assessed SROI at varying discount rates of 0-10%. RESULTS: The mathematical model yielded NPVs of US$235,511 in investments and US$8,497,183 in benefits. This suggested a return of US$36.08 for each dollar invested, ranging from US$31.66-US39.00 for varying discount rate scenarios. CONCLUSIONS: The evaluated CHW-based TB intervention generated substantial individual and societal benefits. The SROI methodology may be an alternative for the economic evaluation of healthcare interventions.


Assuntos
Agentes Comunitários de Saúde , Tuberculose , Humanos , Análise Custo-Benefício , Vietnã/epidemiologia , Cidades , Tuberculose/terapia , Tuberculose/epidemiologia
17.
BMC Public Health ; 23(1): 2372, 2023 12 03.
Artigo em Inglês | MEDLINE | ID: mdl-38042797

RESUMO

BACKGROUND: Globally, most people with multidrug-resistant tuberculosis (MDR-TB) and their households experience catastrophic costs of illness, diagnosis, and care. However, the factors associated with experiencing catastrophic costs are poorly understood. This study aimed to identify risk factors associated with catastrophic costs incurrence among MDR-TB-affected households in Ho Chi Minh City (HCMC), Viet Nam. METHODS: Between October 2020 and April 2022, data were collected using a locally-adapted, longitudinal WHO TB Patient Cost Survey in ten districts of HCMC. Ninety-four people with MDR-TB being treated with a nine-month TB regimen were surveyed at three time points: after two weeks of treatment initiation, completion of the intensive phase and the end of the treatment (approximately five and 10 months post-treatment initiation respectively). The catastrophic costs threshold was defined as total TB-related costs exceeding 20% of annual pre-TB household income. Logistic regression was used to identify variables associated with experiencing catastrophic costs. A sensitivity analysis examined the prevalence of catastrophic costs using alternative thresholds and cost estimation approaches. RESULTS: Most participants (81/93 [87%]) experienced catastrophic costs despite the majority 86/93 (93%) receiving economic support through existing social protection schemes. Among participant households experiencing and not experiencing catastrophic costs, median household income was similar before MDR-TB treatment. However, by the end of MDR-TB treatment, median household income was lower (258 [IQR: 0-516] USD vs. 656 [IQR: 462-989] USD; p = 0.003), and median income loss was higher (2838 [IQR: 1548-5418] USD vs. 301 [IQR: 0-824] USD; p < 0.001) amongst the participant households who experienced catastrophic costs. Being the household's primary income earner before MDR-TB treatment (aOR = 11.2 [95% CI: 1.6-80.5]), having a lower educational level (aOR = 22.3 [95% CI: 1.5-344.1]) and becoming unemployed at the beginning of MDR-TB treatment (aOR = 35.6 [95% CI: 2.7-470.3]) were associated with experiencing catastrophic costs. CONCLUSION: Despite good social protection coverage, most people with MDR-TB in HCMC experienced catastrophic costs. Incurrence of catastrophic costs was independently associated with being the household's primary income earner or being unemployed. Revision and expansion of strategies to mitigate TB-related catastrophic costs, in particular avoiding unemployment and income loss, are urgently required.


Assuntos
Custos de Cuidados de Saúde , Tuberculose Resistente a Múltiplos Medicamentos , Humanos , Estudos Prospectivos , Vietnã/epidemiologia , Tuberculose Resistente a Múltiplos Medicamentos/tratamento farmacológico , Tuberculose Resistente a Múltiplos Medicamentos/epidemiologia , Renda
18.
Int J Solids Struct ; 2752023 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-39035345

RESUMO

We conduct a finite element computational study of the dynamics of a thin elastic film bonded to a much thicker viscous substrate undergoing compression at a fixed rate. The applied compression tends to continuously increase the strain, and hence the elastic energy, of the film. In contrast to the well-studied case of a soft elastic substrate, a viscous substrate cannot store elastic energy; instead it regulates the kinetics of the various mechanisms that dissipate elastic energy of the film. Sufficiently short films remain flat because shear flow in the liquid near the ends allows rapid relaxation of the strain over the entire film length. In longer films, end-relaxation cannot relax film strain in the mid-section, which therefore buckles. Buckles initially appear as packets of approximately-sinusoidal wrinkles. With increasing strain, these packets transform into tall localized ridges separated by nearly flat regions. In all cases, the buckles cause end-relaxation to become dynamically confined to a narrow region near the ends We construct a state map identifying regions of the parameter space of strain vs film length in which the film remains flat, develops wrinkle packets, or develops localized ridges. The evolution of the film energy during continuous compression shows that ridge localization appears due to a competition between two effects: a well-spaced ridges offer a lower energy state than uniform wrinkles, but wrinkles can develop faster because they require the viscous fluid to move over shorter distances.

19.
Int J Mol Sci ; 24(4)2023 Feb 18.
Artigo em Inglês | MEDLINE | ID: mdl-36835521

RESUMO

Nanotechnology has great potential to significantly advance the biomedical field for the benefit of human health. However, the limited understanding of nano-bio interactions leading to unknowns about the potential adverse health effects of engineered nanomaterials and to the poor efficacy of nanomedicines has hindered their use and commercialization. This is well evidenced considering gold nanoparticles, one of the most promising nanomaterials for biomedical applications. Thus, a fundamental understanding of nano-bio interactions is of interest to nanotoxicology and nanomedicine, enabling the development of safe-by-design nanomaterials and improving the efficacy of nanomedicines. In this review, we introduce the advanced approaches currently applied in nano-bio interaction studies-omics and systems toxicology-to provide insights into the biological effects of nanomaterials at the molecular level. We highlight the use of omics and systems toxicology studies focusing on the assessment of the mechanisms underlying the in vitro biological responses to gold nanoparticles. First, the great potential of gold-based nanoplatforms to improve healthcare along with the main challenges for their clinical translation are presented. We then discuss the current limitations in the translation of omics data to support risk assessment of engineered nanomaterials.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Nanoestruturas , Humanos , Ouro , Nanotecnologia , Nanomedicina
20.
Molecules ; 28(22)2023 Nov 16.
Artigo em Inglês | MEDLINE | ID: mdl-38005345

RESUMO

Thickener, also known as a gelling agent, is a critical component of lubricating greases. The most critical property of thickener, temperature resistance, is determined by the molecular structure of the compounds. Currently, all high-temperature-resistant thickeners are based on 12-hydroxystearic acid, which is exclusively produced from castor oil. Since castor oil is also an important reagent for other processes, finding a sustainable alternative to 12-hydroxystearic acid has significant economic implications. This study synthesises an alternative thickener from abundant agricultural waste, cashew nut shell liquor (CNSL). The synthesis and separation procedure contains three steps: (i) forming and separating calcium anacardate by precipitation, (ii) forming and separating anacardic acid (iii) forming lithium anacardate. The obtained lithium anacardate can be used as a thickener for lubricating grease. It was found that the recovery of anacardic acid was around 80%. The optimal reaction temperature and time conditions for lithium anacardate were 100 °C and 1 h, respectively. The method provides an economical alternative to castor and other vegetable oils. The procedure presents a simple pathway to produce the precursor for the lubricating grease from agricultural waste. The first reaction step can be combined with the existing distillation of cashew nut shell processing. An effective application can promote CNSL to a sustainable feedstock for green chemistry. The process can also be combined with recycled lithium from the spent batteries to improve the sustainability of the battery industry.

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