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1.
Cell ; 140(5): 631-42, 2010 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-20211133

RESUMO

Genome sequences of diverse free-living protists are essential for understanding eukaryotic evolution and molecular and cell biology. The free-living amoeboflagellate Naegleria gruberi belongs to a varied and ubiquitous protist clade (Heterolobosea) that diverged from other eukaryotic lineages over a billion years ago. Analysis of the 15,727 protein-coding genes encoded by Naegleria's 41 Mb nuclear genome indicates a capacity for both aerobic respiration and anaerobic metabolism with concomitant hydrogen production, with fundamental implications for the evolution of organelle metabolism. The Naegleria genome facilitates substantially broader phylogenomic comparisons of free-living eukaryotes than previously possible, allowing us to identify thousands of genes likely present in the pan-eukaryotic ancestor, with 40% likely eukaryotic inventions. Moreover, we construct a comprehensive catalog of amoeboid-motility genes. The Naegleria genome, analyzed in the context of other protists, reveals a remarkably complex ancestral eukaryote with a rich repertoire of cytoskeletal, sexual, signaling, and metabolic modules.


Assuntos
Evolução Biológica , Naegleria/genética , Eucariotos/classificação , Eucariotos/genética , Flagelos/metabolismo , Dados de Sequência Molecular , Naegleria/metabolismo , Filogenia , Proteínas de Protozoários/análise , Proteínas de Protozoários/genética
2.
Am J Respir Crit Care Med ; 209(12): 1431-1440, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38236192

RESUMO

Rationale: The term "pre-chronic obstructive pulmonary disease" ("pre-COPD") refers to individuals at high risk of developing COPD who do not meet conventional spirometric criteria for airflow obstruction. New approaches to identifying these individuals are needed, particularly in younger populations. Objectives: To determine whether lung function thresholds and respiratory symptoms can be used to identify individuals at risk of developing COPD. Methods: The Tasmanian Longitudinal Health Study comprises a population-based cohort first studied in 1968 (at age 7 yr). Respiratory symptoms, pre- and post-bronchodilator (BD) spirometry, diffusing capacity, and static lung volumes were measured in a subgroup at age 45, and the incidence of COPD was assessed at age 53. For each lung function measure, z-scores were calculated using Global Lung Function Initiative references. The optimal threshold for best discrimination of COPD incidence was determined by the unweighted Youden index. Measurements and Main Results: Among 801 participants who did not have COPD at age 45, the optimal threshold for COPD incidence by age 53 was pre-BD FEV1/FVC z-score less than -1.264, corresponding to the lowest 10th percentile. Those below this threshold had a 36-fold increased risk of developing COPD over an 8-year follow-up period (risk ratio, 35.8; 95% confidence interval, 8.88 to 144), corresponding to a risk difference of 16.4% (95% confidence interval, 3.7 to 67.4). The sensitivity was 88%, and the specificity was 87%. Positive and negative likelihood ratios were 6.79 and 0.14, respectively. Respiratory symptoms, post-BD spirometry, diffusing capacity, and static lung volumes did not improve on the classification achieved by pre-BD FEV1/FVC alone. Conclusions: This is the first study, to our knowledge, to evaluate the discriminatory accuracy of spirometry, diffusing capacity, and static lung volume thresholds for COPD incidence in middle-aged adults. Our findings support the inclusion of pre-BD spirometry in the physiological definition of pre-COPD and indicate that pre-BD FEV1/FVC at the 10th percentile accurately identifies individuals at high risk of developing COPD in community-based settings.


Assuntos
Doença Pulmonar Obstrutiva Crônica , Espirometria , Humanos , Doença Pulmonar Obstrutiva Crônica/fisiopatologia , Doença Pulmonar Obstrutiva Crônica/diagnóstico , Doença Pulmonar Obstrutiva Crônica/epidemiologia , Masculino , Feminino , Pessoa de Meia-Idade , Estudos Prospectivos , Espirometria/métodos , Tasmânia/epidemiologia , Incidência , Estudos Longitudinais , Estudos de Coortes , Testes de Função Respiratória/métodos , Volume Expiratório Forçado , Capacidade Vital , Adulto
3.
Antimicrob Agents Chemother ; 68(5): e0168623, 2024 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-38534103

RESUMO

Nocardiosis typically requires a prolonged treatment duration of ≥6 months and initial combination therapy with 2-3 antibiotics. First-line regimens for nocardiosis are associated with considerable toxicity; therefore, alternative therapies are needed. Omadacycline is an aminomethylcycline with broad antimicrobial activity whose in vitro activity against Nocardia species has not been formally assessed. The in vitro potency of omadacycline was evaluated against 300 Nocardia clinical isolates by broth microdilution. The most common Nocardia species tested were N. cyriacigeorgica (21%), N. nova (20%), and N. farcinica (12%). The most common specimens were respiratory (178 isolates, 59%) and wound (57 isolates, 19%). Omadacycline minimum inhibitory concentrations (MICs) across all Nocardia species ranged from 0.06 µg/mL to 8 µg/mL, with an MIC50 of 2 µg/mL and MIC90 of 4 µg/mL. The lowest MICs were found among N. paucivorans (MIC50 = 0.25 µg/mL, MIC90 = 0.25 µg/mL), N. asiatica (MIC50 = 0.25 µg/mL, MIC90 = 1 µg/mL), N. abscessus complex (MIC50 = 0.5 µg/mL, MIC90 = 1 µg/mL), N. beijingensis (MIC50 = 0.5 µg/mL, MIC90 = 2 µg/mL), and N. otitidiscaviarum (MIC50 = 1 µg/mL, MIC90 = 2 µg/mL). The highest MICs were found among N. farcinica (MIC50 = 4 µg/mL, MIC90 = 8 µg/mL). In vitro potency differed by species among Nocardia clinical isolates. Further studies are warranted to evaluate the potential clinical utility of omadacycline for nocardiosis.


Assuntos
Antibacterianos , Testes de Sensibilidade Microbiana , Nocardiose , Nocardia , Tetraciclinas , Nocardia/efeitos dos fármacos , Tetraciclinas/farmacologia , Antibacterianos/farmacologia , Humanos , Nocardiose/microbiologia , Nocardiose/tratamento farmacológico
4.
Am J Pathol ; 193(12): 2133-2143, 2023 12.
Artigo em Inglês | MEDLINE | ID: mdl-37544503

RESUMO

Although approximately 70% of bladder cancers are noninvasive and have high recurrence rates, early-stage disease is understudied. The lack of models to validate the contribution of molecular drivers of bladder tumorigenesis is a significant issue. Although mutations in PIK3CA are frequent in human bladder cancer, an in vivo model for understanding their contribution to bladder tumorigenesis is unavailable. Therefore, a Upk2-Cre/Pik3caH1047R mouse model expressing one or two R26-Pik3caH1047R alleles in a urothelium-specific manner was generated. Pik3caH1047R functionality was confirmed by quantifying Akt phosphorylation, and mice were characterized by assessing urothelial thickness, nuclear atypia, and expression of luminal and basal markers at 6 and 12 months of age. While at 6 months, Pik3caH1047R mice developed increased urothelial thickness and nuclear atypia, progressive disease was not observed at 12 months. Immunohistochemistry showed urothelium maintained luminal differentiation characterized by high forkhead box A1 (Foxa1) and peroxisome proliferator-activated receptor γ expression. Surprisingly, Pik3caH1047R mice subjected to low-dose carcinogen exposure [N-butyl-N-(4-hydroxybutyl)nitrosamine] exhibited no significant differences after exposure relative to mice without exposure. Furthermore, single-sample gene set enrichment analysis of invasive human tumors showed those with mutant PIK3CA did not exhibit significantly increased phosphatidylinositol 3-kinase/AKT pathway activity compared with wild-type PIK3CA tumors. Overall, these data suggest that Pik3caH1047R can elicit early tumorigenic changes in the urothelium, but progression to invasion may require additional genetic alterations.


Assuntos
Proteínas Proto-Oncogênicas c-akt , Neoplasias da Bexiga Urinária , Animais , Humanos , Camundongos , Carcinogênese/genética , Classe I de Fosfatidilinositol 3-Quinases/genética , Mutação , Proteínas Proto-Oncogênicas c-akt/metabolismo , Neoplasias da Bexiga Urinária/genética , Neoplasias da Bexiga Urinária/patologia , Urotélio/metabolismo
5.
Soft Matter ; 20(27): 5273-5295, 2024 Jul 10.
Artigo em Inglês | MEDLINE | ID: mdl-38952198

RESUMO

Silicone is frequently used as a model system to investigate and tune wetting on soft materials. Silicone is biocompatible and shows excellent thermal, chemical, and UV stability. Moreover, the mechanical properties of the surface can be easily varied by several orders of magnitude in a controlled manner. Polydimethylsiloxane (PDMS) is a popular choice for coating applications such as lubrication, self-cleaning, and drag reduction, facilitated by low surface energy. Aiming to understand the underlying interactions and forces, motivated numerous and detailed investigations of the static and dynamic wetting behavior of drops on PDMS-based surfaces. Here, we recognize the three most prevalent PDMS surface variants, namely liquid-infused (SLIPS/LIS), elastomeric, and liquid-like (SOCAL) surfaces. To understand, optimize, and tune the wetting properties of these PDMS surfaces, we review and compare their similarities and differences by discussing (i) the chemical and molecular structure, and (ii) the static and dynamic wetting behavior. We also provide (iii) an overview of methods and techniques to characterize PDMS-based surfaces and their wetting behavior. The static and dynamic wetting ridge is given particular attention, as it dominates energy dissipation, adhesion, and friction of sliding drops and influences the durability of the surfaces. We also discuss special features such as cloaking and wetting-induced phase separation. Key challenges and opportunities of these three surface variants are outlined.

6.
Med J Aust ; 220(1): 35-45, 2024 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-37982357

RESUMO

INTRODUCTION: Cough is the most common symptom leading to medical consultation. Chronic cough results in significant health care costs, impairs quality of life, and may indicate the presence of a serious underlying condition. Here, we present a summary of an updated position statement on cough management in the clinical consultation. MAIN RECOMMENDATIONS: Assessment of children and adults requires a focused history of chronic cough to identify any red flag cough pointers that may indicate an underlying disease. Further assessment with examination should include a chest x-ray and spirometry (when age > 6 years). Separate paediatric and adult diagnostic management algorithms should be followed. Management of the underlying condition(s) should follow specific disease guidelines, as well as address adverse environmental exposures and patient/carer concerns. First Nations adults and children should be considered a high risk group. The full statement from the Thoracic Society of Australia and New Zealand and Lung Foundation Australia for managing chronic cough is available at https://lungfoundation.com.au/resources/cicada-full-position-statement. CHANGES IN MANAGEMENT AS A RESULT OF THIS STATEMENT: Algorithms for assessment and diagnosis of adult and paediatric chronic cough are recommended. High quality evidence supports the use of child-specific chronic cough management algorithms to improve clinical outcomes, but none exist in adults. Red flags that indicate serious underlying conditions requiring investigation or referral should be identified. Early and effective treatment of chronic wet/productive cough in children is critical. Culturally specific strategies for facilitating the management of chronic cough in First Nations populations should be adopted. If the chronic cough does not resolve or is unexplained, the patient should be referred to a respiratory specialist or cough clinic.


Assuntos
Tosse Crônica , Hemípteros , Adulto , Criança , Humanos , Animais , Doença Crônica , Qualidade de Vida , Tosse/diagnóstico , Tosse/etiologia , Tosse/terapia , Austrália
7.
Mol Ther ; 31(12): 3564-3578, 2023 Dec 06.
Artigo em Inglês | MEDLINE | ID: mdl-37919903

RESUMO

Chimeric antigen receptor (CAR) T cell therapy has been successful for hematological malignancies. Still, a lack of efficacy and potential toxicities have slowed its application for other indications. Furthermore, CAR T cells undergo dynamic expansion and contraction in vivo that cannot be easily predicted or controlled. Therefore, the safety and utility of such therapies could be enhanced by engineered mechanisms that engender reversible control and quantitative monitoring. Here, we use a genetic tag based on the enzyme Escherichia coli dihydrofolate reductase (eDHFR), and derivatives of trimethoprim (TMP) to modulate and monitor CAR expression and T cell activity. We fused eDHFR to the CAR C terminus, allowing regulation with TMP-based proteolysis-targeting chimeric small molecules (PROTACs). Fusion of eDHFR to the CAR does not interfere with cell signaling or its cytotoxic function, and the addition of TMP-based PROTACs results in a reversible and dose-dependent inhibition of CAR activity via the proteosome. We show the regulation of CAR expression in vivo and demonstrate imaging of the cells with TMP radiotracers. In vitro immunogenicity assays using primary human immune cells and overlapping peptide fragments of eDHFR showed no memory immune repertoire for eDHFR. Overall, this translationally-orientied approach allows for temporal monitoring and image-guided control of cell-based therapies.


Assuntos
Imunoterapia Adotiva , Linfócitos T , Humanos , Imunoterapia Adotiva/métodos , Tetra-Hidrofolato Desidrogenase/genética , Tetra-Hidrofolato Desidrogenase/metabolismo , Receptores de Antígenos de Linfócitos T/genética
8.
Am J Respir Crit Care Med ; 208(2): 132-141, 2023 07 15.
Artigo em Inglês | MEDLINE | ID: mdl-37209134

RESUMO

Rationale: Asthma is a heterogeneous condition, and longitudinal phenotyping may provide new insights into the origins and outcomes of the disease. Objectives: We aimed to characterize the longitudinal phenotypes of asthma between the first and sixth decades of life in a population-based cohort study. Methods: Respiratory questionnaires were collected at seven time points in the TAHS (Tasmanian Longitudinal Health Study) when participants were aged 7, 13, 18, 32, 43, 50, and 53 years. Current-asthma and ever-asthma status was determined at each time point, and group-based trajectory modeling was used to characterize distinct longitudinal phenotypes. Linear and logistic regression models were fitted to investigate associations of the longitudinal phenotypes with childhood factors and adult outcomes. Measurements and Main Results: Of 8,583 original participants, 1,506 had reported ever asthma. Five longitudinal asthma phenotypes were identified: early-onset adolescent-remitting (40%), early-onset adult-remitting (11%), early-onset persistent (9%), late-onset remitting (13%), and late-onset persistent (27%). All phenotypes were associated with chronic obstructive pulmonary disease at age 53 years, except for late-onset remitting asthma (odds ratios: early-onset adolescent-remitting, 2.00 [95% confidence interval (CI), 1.13-3.56]; early-onset adult-remitting, 3.61 [95% CI, 1.30-10.02]; early-onset persistent, 8.73 [95% CI, 4.10-18.55]; and late-onset persistent, 6.69 [95% CI, 3.81-11.73]). Late-onset persistent asthma was associated with the greatest comorbidity at age 53 years, with increased risk of mental health disorders and cardiovascular risk factors. Conclusions: Five longitudinal asthma phenotypes were identified between the first and sixth decades of life, including two novel remitting phenotypes. We found differential effects of these phenotypes on risk of chronic obstructive pulmonary disease and nonrespiratory comorbidities in middle age.


Assuntos
Asma , Doença Pulmonar Obstrutiva Crônica , Criança , Humanos , Estudos de Coortes , Asma/genética , Estudos Longitudinais , Fenótipo , Fatores de Risco
9.
Am J Gastroenterol ; 2023 Oct 09.
Artigo em Inglês | MEDLINE | ID: mdl-37811776

RESUMO

INTRODUCTION: Limited data exist evaluating antiobesity medications (AOM) in patients with inflammatory bowel disease (IBD). METHODS: We performed a case-control study evaluating the effectiveness and safety of AOM in patients with IBD with obesity, matched to non-IBD controls. RESULTS: After 12 months, the case (n = 36) and control (n = 36) groups achieved similar percent total body weight loss of -6.9 ± 8.3 and -8.1 ± 7.0 (P = 0.30), respectively. Side effect profiles were similar between groups. Seven patients experienced an IBD flare, all managed medically. DISCUSSION: AOM use in patients with IBD demonstrated similar effectiveness and safety when compared with that observed in the non-IBD population.

10.
Curr Opin Infect Dis ; 36(4): 228-234, 2023 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-37431553

RESUMO

PURPOSE OF REVIEW: Nucleic acid sequence-based organism identification plays an important role in the diagnosis and management of transplant and cancer-associated infectious diseases. Here, we provide a high-level overview of advanced sequencing technologies, discuss test performance, and highlight unmet research needs with a focus on immunocompromised hosts. RECENT FINDINGS: Next-generation sequencing (NGS) technologies are powerful tools with a growing role in managing immunocompromised patients with suspected infection. Targeted NGS (tNGS) can identify pathogens directly from patient specimens, especially for mixed samples, and has been used to detect resistance mutations in transplant-related viruses (e.g. CMV). Whole-genome sequencing (WGS) is increasingly used for outbreak investigations and infection control. Metagenomic NGS (mNGS) is useful for hypothesis-free testing and can simultaneously assess pathogens and host response to infection. SUMMARY: NGS testing increases diagnostic yield relative to standard culture and Sanger sequencing but may be limited by high cost, turnaround times, and detection of unexpected organisms or commensals of uncertain significance. Close collaboration with the clinical microbiology laboratory and infectious diseases is recommended when NGS testing is considered. Additional research is required to understand which immunocompromised patients are most likely to benefit from NGS testing, and when testing should ideally be performed.


Assuntos
Serviços de Laboratório Clínico , Doenças Transmissíveis , Viroses , Humanos , Medicina de Precisão , Viroses/diagnóstico , Sequenciamento de Nucleotídeos em Larga Escala
11.
Clin Exp Allergy ; 53(9): 911-929, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37401045

RESUMO

BACKGROUND: Previous systematic reviews have focused on associations between single time point measures of Body Mass Index (BMI) and asthma and allergic diseases. As BMI changes dynamically during childhood, examination of associations between longitudinal trajectories in BMI and allergic diseases is needed to fully understand the nature of these relationships. OBJECTIVE: To systematically synthesise the association between BMI trajectories in childhood (0-18 years) and allergic diseases (asthma, eczema, allergic rhinitis, or food allergies outcomes). DESIGN: We conducted a systematic review following the PRISMA guidelines, and two independent reviewers assessed the study quality using the ROBINS-E and GRADE tools. A narrative synthesis was performed as the statistical heterogeneity did not allow a meta-analysis. DATA SOURCES: A search was performed on PubMed and EMBASE databases on 4th January 2023. ELIGIBILITY CRITERIA: Longitudinal cohort studies assessing the associations between childhood BMI trajectories and allergic diseases were included. RESULTS: Eleven studies met the inclusion criteria with a total of 37,690 participants between 0 and 53 years of age. Ten studies examined asthma outcomes, three assessed association with allergic rhinitis, two assessed eczema, and one assessed food allergy. High heterogeneity and high risk of bias were observed. Overall, the quality of evidence was very low. Nevertheless, two consistent findings were identified: (1) a persistently high BMI between 6 and 10 years of age may be associated with an increased risk of asthma at 18 years and (2) a rapid increase in BMI in the first 2 years of life may be associated with subsequent asthma. CONCLUSIONS: Maintaining a normal BMI trajectory during childhood may reduce the risk of asthma. Future research that adequately addresses confounding and includes longer-term follow-up is needed. Moreover, additional studies examining potential associations with eczema, food allergies, and allergic rhinitis outcomes are needed.

12.
Phys Rev Lett ; 130(5): 058205, 2023 Feb 03.
Artigo em Inglês | MEDLINE | ID: mdl-36800444

RESUMO

Drops in contact with swollen, elastomeric substrates can induce a capillary mediated phase separation in wetting ridges. Using confocal microscopy, we visualize phase separation of oligomeric silicone oil from a cross-linked silicone network during steady-state sliding of water drops. We find an inverse relationship between the oil tip height and the drop sliding speed, which is rationalized by competing transport timescales of the oil molecules: separation rate versus drop-advection speed. Separation rates in highly swollen networks are as fast as diffusion in pure melts.

13.
Allergy ; 78(9): 2418-2427, 2023 09.
Artigo em Inglês | MEDLINE | ID: mdl-36940306

RESUMO

BACKGROUND: Multidisciplinary systematic assessment improves outcomes in difficult-to-treat asthma, but without clear response predictors. Using a treatable-traits framework, we stratified patients by trait profile, examining clinical impact and treatment responsiveness to systematic assessment. METHODS: We performed latent class analysis using 12 traits on difficult-to-treat asthma patients undergoing systematic assessment at our institution. We examined Asthma Control Questionnaire (ACQ-6) and Asthma Quality of Life Questionnaire (AQLQ) scores, FEV1 , exacerbation frequency, and maintenance oral corticosteroid (mOCS) dose, at baseline and following systematic assessment. RESULTS: Among 241 patients, two airway-centric profiles were characterized by early-onset with allergic rhinitis (n = 46) and adult onset with eosinophilia/chronic rhinosinusitis (n = 60), respectively, with minimal comorbid or psychosocial traits; three non-airway-centric profiles exhibited either comorbid (obesity, vocal cord dysfunction, dysfunctional breathing) dominance (n = 51), psychosocial (anxiety, depression, smoking, unemployment) dominance (n = 72), or multi-domain impairment (n = 12). Compared to airway-centric profiles, non-airway-centric profiles had worse baseline ACQ-6 (2.7 vs. 2.2, p < .001) and AQLQ (3.8 vs. 4.5, p < .001) scores. Following systematic assessment, the cohort showed overall improvements across all outcomes. However, airway-centric profiles had more FEV1 improvement (5.6% vs. 2.2% predicted, p < .05) while non-airway-centric profiles trended to greater exacerbation reduction (1.7 vs. 1.0, p = .07); mOCS dose reduction was similar (3.1 mg vs. 3.5 mg, p = .782). CONCLUSION: Distinct trait profiles in difficult-to-treat asthma are associated with different clinical outcomes and treatment responsiveness to systematic assessment. These findings yield clinical and mechanistic insights into difficult-to-treat asthma, offer a conceptual framework to address disease heterogeneity, and highlight areas responsive to targeted intervention.


Assuntos
Asma , Qualidade de Vida , Adulto , Humanos , Asma/diagnóstico , Asma/tratamento farmacológico , Asma/epidemiologia , Comorbidade , Respiração , Ansiedade , Corticosteroides/uso terapêutico
14.
Epilepsia ; 64(10): 2771-2780, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-37392445

RESUMO

OBJECTIVE: Individuals with epilepsy often have memory difficulties, and older adults with epilepsy are especially vulnerable, due to the additive effect of aging. The goal of this study was to assess factors that are associated with 24-h memory retention in older adults with epilepsy. METHODS: Fifty-five adults with epilepsy, all aged >50 years, performed a declarative memory task involving the recall of the positions of 15 card pairs on a computer screen prior to a 24-h ambulatory electroencephalogram (EEG). We assessed the percentage of encoded card pairs that were correctly recalled after 24 h (24-h retention rate). EEGs were evaluated for the presence and frequency of scalp interictal epileptiform activity (IEA) and scored for total sleep. Global slow wave activity (SWA) power during non-rapid eye movement sleep was also calculated. RESULTS: Forty-four participants successfully completed the memory task. Two were subsequently excluded due to seizures on EEG. The final cohort (n = 42) had a mean age of 64.3 ± 7.5 years, was 52% female, and had an average 24-h retention rate of 70.9% ± 30.2%. Predictors of 24-h retention based on multivariate regression analysis when controlling for age, sex, and education included number of antiseizure medications (ß = -.20, p = .013), IEA frequency (ß = -.08, p = .0094), and SWA power (ß = +.002, p = .02). SIGNIFICANCE: In older adults with epilepsy, greater frequency of IEA, reduced SWA power, and higher burden of antiseizure medications correlated with worse 24-h memory retention. These factors represent potential treatment targets to improve memory in older adults with epilepsy.


Assuntos
Epilepsia , Sono , Humanos , Feminino , Idoso , Pessoa de Meia-Idade , Masculino , Memória , Epilepsia/complicações , Convulsões , Rememoração Mental , Eletroencefalografia
15.
Soft Matter ; 19(33): 6247-6254, 2023 Aug 23.
Artigo em Inglês | MEDLINE | ID: mdl-37555264

RESUMO

The attachment and detachment of microparticles at a liquid-liquid interface are common in many material systems, from Pickering emulsions and colloidal assemblies to capillary suspensions. Properties of these systems rely on how the particles interact with the liquid-liquid interface, including the detachment process. In this study, we simultaneously measure the capillary detachment force of a microparticle from a liquid-liquid interface and visualize the shape of the meniscus by combining colloidal probe microscopy and confocal microscopy. The capillary behavior is studied on both untreated (hydrophilic) and fluorinated (hydrophobic) glass microparticles. The measured force data show good agreement with theoretical calculations based on the extracted geometric parameters from confocal images of the capillary bridge. It is also evident that contact line pinning is an important aspect of detachment for both untreated and fluorinated particles.

16.
Int J Colorectal Dis ; 38(1): 39, 2023 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-36781513

RESUMO

BACKGROUND: Cronkhite-Canada syndrome (CCS) is considered a relentlessly progressive disease with high mortality rates. Although disease understanding and treatment options have greatly improved, the prognosis from these advancements has not been well documented. This study aimed to evaluate treatment outcomes and overall survival of CCS. METHODS: Seventeen patients who were diagnosed and treated over a 20-year period at Mayo Clinic (Rochester, Minnesota) were included. Data were abstracted, which included clinical and endoscopic manifestations, treatment course, and survival outcomes. RESULTS: The median (interquartile range) duration of follow-up was 8.3 (3.7-15.8) years. All patients received an initial prednisone dose equivalence of 30-80 mg daily, and five patients required steroids at the time of the last follow-up. Twelve patients trialed thiopurine therapy, and ten patients continued with a thiopurine until the last follow-up. Fifteen patients achieved clinical complete remission, and eleven patients achieved endoscopic complete remission after pharmacotherapy initiation. Seven patients required gastrointestinal surgeries during their disease course. The 5-year overall survival was 93.3% (95% confidence interval (CI): 81.5-100%), and the 3-year relapse-free survival was 82.4% (95% CI: 66.1-100%). CONCLUSION: The prognosis and overall survival of patients with CCS have markedly improved with advancement in disease understanding and therapies. Pharmacotherapy, including corticosteroids and immunomodulators, is effective in inducing and maintaining remission, and gastrointestinal surgery is commonly needed as an adjunct for managing CCS disease complications.


Assuntos
Corticosteroides , Polipose Intestinal , Humanos , Corticosteroides/uso terapêutico , Prognóstico , Resultado do Tratamento , Indução de Remissão , Polipose Intestinal/tratamento farmacológico , Polipose Intestinal/complicações
17.
Macromol Rapid Commun ; 44(20): e2300304, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37585219

RESUMO

Understanding how small molecules penetrate and contaminate polymer films is of vital importance for developing protective coatings for a wide range of applications. To this end, rhodamine B fluorescent dye is visualized diffusing through polystyrene-polydimethylsiloxane block copolymer (BCP) coatings using confocal microscopy. The intensity of dye inside the coatings grows and decays non-monotonically, which is likely due to a combination of dye molecule transport occurring concurrently in different directions. An empirical fitting equation allows for comparing the contamination rates between copolymers, demonstrating that dye penetration is related to the chemical makeup and configuration of the BCPs. This work shows that confocal microscopy can be a useful tool to visualize the transport of a fluorophore in space and time through a coating.


Assuntos
Corantes Fluorescentes , Polímeros , Polímeros/química , Corantes Fluorescentes/química , Poliestirenos
18.
Intern Med J ; 53(10): 1790-1795, 2023 10.
Artigo em Inglês | MEDLINE | ID: mdl-36448650

RESUMO

BACKGROUND: Information on inappropriate dosing of direct oral anticoagulants (DOACs) is scarce in the Australian context. AIM: To describe the prevalence and potential predictors of inappropriate dosing of DOACs. METHODS: Patients who received DOACs during admission under a general medical unit over a 2-year period (from January 2017 to December 2018) were retrospectively studied. Appropriateness of the dosing regimen was verified against the recommendations of the Therapeutic Goods Administration of Australia. Data were obtained from medical records and analysed in univariate and multivariate logistic regression models. The variables associated with under- and overdosing were also determined. RESULTS: A total of 203 (mean age 71.6 ± 14.5 years, females 52%) patients were studied. Inappropriate dosing occurred in 44 (22%) patients: underdosing 27 (13%) and overdosing 17 (8%). Age ≥75 years (P < 0.01), lower estimated creatinine clearance (CrCl) (P < 0.01), prescription of DOAC prior to index admission (P < 0.01) and higher Charlson Comorbidity Index (P < 0.01), HAS-BLED (P < 0.01) and CHA2 DS2 -VASc (P < 0.01) scores had a significant univariate association with inappropriate dosing. However, in the multivariate logistic regression only lower CrCl (odds ratio (OR) 1.04, 95% confidence interval (CI): 1.01-1.07, P < 0.01) and prescription of DOAC prior to index admission (OR 2.62, 95% CI: 1.01-6.75, P = 0.047) remained significantly associated with inappropriate dosing. Impaired renal function also had a significant association with underdosing (OR 1.04, 95% CI: 1.01-1.07, P = 0.01) and borderline significance with overdosing (OR 1.03, 95% CI: 1.00-1.07, P = 0.06). CONCLUSION: Inappropriate dosing of DOACs, especially underdosing, is common in clinical practice. Clinicians should exercise due diligence when prescribing DOACs to patients with renal impairment and in outpatient settings.


Assuntos
Fibrilação Atrial , Overdose de Drogas , Insuficiência Renal , Acidente Vascular Cerebral , Feminino , Humanos , Pessoa de Meia-Idade , Idoso , Idoso de 80 Anos ou mais , Anticoagulantes/uso terapêutico , Prevalência , Estudos Retrospectivos , Austrália/epidemiologia , Hospitalização , Insuficiência Renal/epidemiologia , Insuficiência Renal/tratamento farmacológico , Overdose de Drogas/tratamento farmacológico , Fibrilação Atrial/epidemiologia , Administração Oral , Acidente Vascular Cerebral/tratamento farmacológico
19.
J Biomech Eng ; 145(3)2023 03 01.
Artigo em Inglês | MEDLINE | ID: mdl-36282508

RESUMO

We propose svMorph, a framework for interactive virtual sculpting of patient-specific vascular anatomic models. Our framework includes three tools for the creation of tortuosity, aneurysms, and stenoses in tubular vascular geometries. These shape edits are performed via geometric operations on the surface mesh and vessel centerline curves of the input model. The tortuosity tool also uses the physics-based Oriented Particles method, coupled with linear blend skinning, to achieve smooth, elastic-like deformations. Our tools can be applied separately or in combination to produce simulation-suitable morphed models. They are also compatible with popular vascular modeling software, such as simvascular. To illustrate our tools, we morph several image-based, patient-specific models to create a range of shape changes and simulate the resulting hemodynamics via three-dimensional, computational fluid dynamics. We also demonstrate the ability to quickly estimate the hemodynamic effects of the shape changes via the automated generation of associated zero-dimensional lumped-parameter models.


Assuntos
Hemodinâmica , Modelos Cardiovasculares , Humanos , Simulação por Computador , Modelos Anatômicos , Hidrodinâmica
20.
Soft Matter ; 18(19): 3698-3704, 2022 May 18.
Artigo em Inglês | MEDLINE | ID: mdl-35485790

RESUMO

The wetting of polymer melts at high temperatures is studied by placing a glycerol drop on a poly(n-butyl methacrylate) film and measuring the wetting ridge. The height of the wetting ridge grows continuously over time. These wetting ridge growth rates can be explained by polymer chain dynamics occurring at the molecular level, determined using oscillatory shear rheology of the polymer melt. The shape of wetting ridge profile can be modeled using an equation previously used for elastomers, with a simple modification that incorporates the time-dependent storage modulus of the uncrosslinked melts.

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