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1.
J R Soc Interface ; 21(215): 20230779, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38903010

ABSTRACT

Many animals employ a second frequency filter beyond the initial filtering of the eardrum (or tympanal membrane). In the field cricket ear, both the filtering mechanism and the transmission path from the posterior tympanal membrane (PTM) have remained unclear. A mismatch between PTM vibrations and sensilla tuning has prompted speculations of a second filter. PTM coupling to the tracheal branches is suggested to support a transmission pathway. Here, we present three independent lines of evidence converging on the same conclusion: the existence of a series of linked membranes with distinct resonant frequencies serving both filtering and transmission functions. Micro-computed tomography (µ-CT) highlighted the 'dividing membrane (DivM)', separating the tracheal branches and connected to the PTM via the dorsal membrane of the posterior tracheal branch (DM-PTB). Thickness analysis showed the DivM to share significant thinness similarity with the PTM. Laser Doppler vibrometry indicated the first of two PTM vibrational peaks, at 6 and 14 kHz, originates not from the PTM but from the coupled DM-PTB. This result was corroborated by µ-CT-based finite element analysis. These findings clarify further the biophysical source of neuroethological pathways in what is an important model of behavioural neuroscience. Tuned microscale coupled membranes may also hold biomimetic relevance.


Subject(s)
Finite Element Analysis , Gryllidae , X-Ray Microtomography , Animals , Gryllidae/physiology , Tympanic Membrane/physiology , Tympanic Membrane/diagnostic imaging , Vibration
2.
3D Print Addit Manuf ; 11(2): 517-528, 2024 Apr 01.
Article in English | MEDLINE | ID: mdl-38689905

ABSTRACT

Photopolymerization-based additive manufacturing requires selectively exposing a feedstock resin to ultraviolet (UV) light, which in digital light processing is achieved either using a digital micromirror device or a digital mask. The minimum tolerances and resolution for a multilayer process are separate for resolution through the Z-axis, looking through the thickness of a printed part, and resolution in the XY-axes, in the plane of the printed layer. The former depends wholly on the rate of attenuation of the incident UV light through the material relative to the mechanical motion of the build layer, while the latter is determined by a two-dimensional pattern of irradiance on the resin formed by the digital micromirror device or the digital mask. The size or the spacing of elements or pixels of this digital mask is frequently given by manufacturers as the "resolution" of the device, however, in practice the achievable resolution is first determined by the beam distribution from each pixel. The beam distribution is, as standard, modeled as a two-parameter Gaussian distribution but the key parameters of peak intensity and standard deviation of the beam are hidden to the user and difficult to measure directly. The ability of models based on the Gaussian distribution to correctly predict the polymerization of printed features in the microscale is also typically poor. In this study, we demonstrate an alternative model of beam distribution based on a heavy-tailed Lorentzian model, which is able to more accurately predict small build areas for both positive and negative features. We show a simple calibration method to derive the key space parameters of the beam distribution from measurements of a single-layer printed model. We propose that the standard Gaussian model is insufficient to accurately predict a print outcome as it neglects higher-order terms, such as beam skew and kurtosis, and in particular failing to account for the relatively heavy tails of the beam distribution. Our results demonstrate how the amendments to the beam distribution can avoid errors in microchannel formation, and better estimates of the true XY-axes resolution of the printer. The results can be used as the basis for voxel-based models of print solidification that allow software prediction of the photopolymerization process.

3.
Materials (Basel) ; 17(10)2024 May 20.
Article in English | MEDLINE | ID: mdl-38793524

ABSTRACT

This study introduces an advanced computational method aimed at accelerating continuum-scale processes using crystal plasticity approaches to predict mechanical responses in cobalt-based superalloys. The framework integrates two levels, namely, sub-grain and homogenized, at the meso-scale through crystal plasticity finite element (CPFE) platforms. The model is applicable across a temperature range from room temperature up to 900 °C, accommodating various dislocation mechanisms in the microstructure. The sub-grain level explicitly incorporates precipitates and employs a dislocation density-based constitutive model that is size-dependent. In contrast, the homogenized level utilizes an activation energy-based constitutive model, implicitly representing the γ' phase for efficiency in computations. This level considers the effects of composition and morphology on mechanical properties, demonstrating the potential for cobalt-based superalloys to rival nickel-based superalloys. The study aims to investigate the impacts of elements including tungsten, tantalum, titanium, and chromium through the homogenized constitutive model. The model accounts for the locking mechanism to address the cross-slip of screw dislocations at lower temperatures as well as the glide and climb mechanism to simulate diffusions at higher temperatures. The model's validity is established across diverse compositions and morphologies, as well as various temperatures, through comparison with experimental data. This advanced computational framework not only enables accurate predictions of mechanical responses in cobalt-based superalloys across a wide temperature range, but also provides valuable insights into the design and optimization of these materials for high-temperature applications.

4.
Clin Sci (Lond) ; 138(8): 537-554, 2024 Apr 24.
Article in English | MEDLINE | ID: mdl-38577922

ABSTRACT

Patients with pulmonary fibrosis (PF) often experience exacerbations of their disease, characterised by a rapid, severe deterioration in lung function that is associated with high mortality. Whilst the pathobiology of such exacerbations is poorly understood, virus infection is a trigger. The present study investigated virus-induced injury responses of alveolar and bronchial epithelial cells (AECs and BECs, respectively) from patients with PF and age-matched controls (Ctrls). Air-liquid interface (ALI) cultures of AECs, comprising type I and II pneumocytes or BECs were inoculated with influenza A virus (H1N1) at 0.1 multiplicity of infection (MOI). Levels of interleukin-6 (IL-6), IL-36γ and IL-1ß were elevated in cultures of AECs from PF patients (PF-AECs, n = 8-11), being markedly higher than Ctrl-AECs (n = 5-6), 48 h post inoculation (pi) (P<0.05); despite no difference in H1N1 RNA copy numbers 24 h pi. Furthermore, the virus-induced inflammatory responses of PF-AECs were greater than BECs (from either PF patients or controls), even though viral loads in the BECs were overall 2- to 3-fold higher than AECs. Baseline levels of the senescence and DNA damage markers, nuclear p21, p16 and H2AXγ were also significantly higher in PF-AECs than Ctrl-AECs and further elevated post-infection. Senescence induction using etoposide augmented virus-induced injuries in AECs (but not viral load), whereas selected senotherapeutics (rapamycin and mitoTEMPO) were protective. The present study provides evidence that senescence increases the susceptibility of AECs from PF patients to severe virus-induced injury and suggests targeting senescence may provide an alternative option to prevent or treat the exacerbations that worsen the underlying disease.


Subject(s)
Alveolar Epithelial Cells , Influenza A Virus, H1N1 Subtype , Pulmonary Fibrosis , Humans , Influenza A Virus, H1N1 Subtype/pathogenicity , Alveolar Epithelial Cells/virology , Alveolar Epithelial Cells/pathology , Alveolar Epithelial Cells/metabolism , Pulmonary Fibrosis/virology , Pulmonary Fibrosis/pathology , Male , Influenza, Human/virology , Influenza, Human/complications , Influenza, Human/pathology , Middle Aged , Female , Cells, Cultured , Aged , Cellular Senescence , Case-Control Studies , Cytokines/metabolism
5.
Aust J Prim Health ; 2024 Feb 15.
Article in English | MEDLINE | ID: mdl-38354727

ABSTRACT

BACKGROUND: Gambling is a growing public health issue in Australia. However, limited research has examined the role of primary health care and social services in routine screening for gambling harm in Australia. This research aimed to explore the enablers and barriers to implementing a co-designed gambling screening model in Fairfield, New South Wales - an area with high gambling expenditure. METHODS: A co-designed gambling screening and referral model for GP and community-based organisations was implemented in Fairfield in 2020. Follow-up interviews were conducted with nine health care professionals who implemented the screening in 130 patients. Thematic analysis generated key barriers and enablers for implementation of this model. RESULTS: Key enablers for the screening model implementation included structural factors (alignment of the screening model with current work), process factors and staffing factors (staff empowerment). However, we also noted process factors as a barrier to implementation, particularly the referral pathway following screening. Other barriers included social and structural factors, such as the complexity of gambling harm and project funding. CONCLUSIONS: Embedding routine screening in primary and community care settings can play a role in treating, reducing and preventing gambling-related harm, and reducing stigma in Fairfield and beyond. Additionally, screening models such as this provide health systems with clear evidence on the level of gambling harm in their community (particularly important in culturally and linguistically diverse communities who are underrepresented in research). This evidence is important for addressing system-level drivers of harm and advocating for political reform to reduce the impact of gambling on communities.

6.
PLoS One ; 19(1): e0296634, 2024.
Article in English | MEDLINE | ID: mdl-38227605

ABSTRACT

BACKGROUND: The application of cold and pressure to the knee is a common part of post-operative rehabilitation. Skin temperature should be reduced to within 10-15 °C to optimise the therapeutic benefits of cryocompression. The purpose of this study was to investigate the ability of five different cryocompression devices to reduce skin temperature to within this therapeutic range. MATERIALS AND METHODS: 32 healthy adult participants (mean (SD): age 26.3 (7.9) years; BMI 24.8 (2.7) kg/m2; 20 males) were recruited for this randomised crossover study. Skin temperature was measured 20 mm distal to the patella using a k-type thermocouple every five minutes during a 30-minute treatment with one of five different cryocompression devices (Physiolab S1, GameReady, Cryo/Cuff, VPulse, and a Gel Wrap). Changes in skin temperature over time were compared to baseline within and between conditions. A subjective rating of comfort was also recorded for each device. RESULTS: The Physiolab S1 and GameReady devices caused significantly lower skin temperatures compared to the VPulse, Gel Wrap, and Cryo/Cuff after 30 minutes (p<0.05). 87-96% reported a positive comfort rating for the Physiolab S1, VPulse, Cryo/Cuff and Gel Wrap, whereas 53% of participants reported a positive comfort rating for the GameReady. CONCLUSIONS: Only the Physiolab S1 and GameReady devices reduced skin temperature of the knee to within the target range of 10-15 °C. The Physiolab S1 was reportedly more comfortable than the GameReady. Clinicians should be aware of the performance differences of different cryocompression devices to understand which is most likely to provide an effective dose of cold therapy to a joint.


Subject(s)
Knee , Skin Temperature , Adult , Male , Humans , Cross-Over Studies , Knee/surgery , Knee Joint , Cryotherapy
7.
Sci Rep ; 13(1): 11200, 2023 07 11.
Article in English | MEDLINE | ID: mdl-37433796

ABSTRACT

Primary air liquid interface (ALI) cultures of bronchial epithelial cells are used extensively to model airway responses. A recent advance is the development of conditional reprogramming that enhances proliferative capability. Several different media and protocols are utilized, yet even subtle differences may influence cellular responses. We compared the morphology and functional responses, including innate immune responses to rhinovirus infection in conditionally reprogrammed primary bronchial epithelial cells (pBECs) differentiated using two commonly used culture media. pBECs collected from healthy donors (n = 5) were CR using g-irradiated 3T3 fibroblasts and Rho Kinase inhibitor. CRpBECs were differentiated at ALI in either PneumaCult (PN-ALI) or bronchial epithelial growth medium (BEGM)-based differentiation media (BEBM:DMEM, 50:50, Lonza)-(AB-ALI) for 28 days. Transepithelial electrical resistance (TEER), immunofluorescence, histology, cilia activity, ion channel function, and expression of cell markers were analyzed. Viral RNA was assessed by RT-qPCR and anti-viral proteins quantified by LEGENDplex following Rhinovirus-A1b infection. CRpBECs differentiated in PneumaCult were smaller and had a lower TEER and cilia beat frequency compared to BEGM media. PneumaCult media cultures exhibited increased FOXJ1 expression, more ciliated cells with a larger active area, increased intracellular mucins, and increased calcium-activated chloride channel current. However, there were no significant changes in viral RNA or host antiviral responses. There are distinct structural and functional differences in pBECs cultured in the two commonly used ALI differentiation media. Such factors need to be taken into consideration when designing CRpBECs ALI experiments for specific research questions.


Subject(s)
Bronchi , Enterovirus Infections , Humans , Cell Differentiation , Epithelial Cells , Chloride Channels , Cilia , Culture Media
8.
Bioinspir Biomim ; 18(5)2023 08 14.
Article in English | MEDLINE | ID: mdl-37499689

ABSTRACT

When looking for novel, simple, and energy-efficient solutions to engineering problems, nature has proved to be an incredibly valuable source of inspiration. The development of acoustic sensors has been a prolific field for bioinspired solutions. With a diverse array of evolutionary approaches to the problem of hearing at small scales (some widely different to the traditional concept of 'ear'), insects in particular have served as a starting point for several designs. From locusts to moths, through crickets and mosquitoes among many others, the mechanisms found in nature to deal with small-scale acoustic detection and the engineering solutions they have inspired are reviewed. The present article is comprised of three main sections corresponding to the principal problems faced by insects, namely frequency discrimination, which is addressed by tonotopy, whether performed by a specific organ or directly on the tympana; directionality, with solutions including diverse adaptations to tympanal structure; and detection of weak signals, through what is known as active hearing. The three aforementioned problems concern tiny animals as much as human-manufactured microphones and have therefore been widely investigated. Even though bioinspired systems may not always provide perfect performance, they are sure to give us solutions with clever use of resources and minimal post-processing, being serious contenders for the best alternative depending on the requisites of the problem.


Subject(s)
Grasshoppers , Hearing , Animals , Humans , Insecta , Biological Evolution , Acoustics
9.
Am J Physiol Lung Cell Mol Physiol ; 325(2): L206-L214, 2023 08 01.
Article in English | MEDLINE | ID: mdl-37280545

ABSTRACT

Bronchoconstriction is the main physiological event in asthma, which leads to worsened clinical symptoms and generates mechanical stress within the airways. Virus infection is the primary cause of exacerbations in people with asthma, however, the impact that bronchoconstriction itself on host antiviral responses and viral replication is currently not well understood. Here we demonstrate how mechanical forces generated during bronchoconstriction may suppress antiviral responses at the airway epithelium without any difference in viral replication. Primary bronchial epithelial cells from donors with asthma were differentiated at the air-liquid interface. Differentiated cells were apically compressed (30 cmH2O) for 10 min every hour for 4 days to mimic bronchoconstriction. Two asthma disease models were developed with the application of compression, either before ("poor asthma control model," n = 7) or following ("exacerbation model," n = 4) rhinovirus (RV) infection. Samples were collected at 0, 24, 48, 72, and 96 h postinfection (hpi). Viral RNA, interferon (IFN)-ß, IFN-λ, and host defense antiviral peptide gene expressions were measured along with IFN-ß, IFN-λ, TGF-ß2, interleukin-6 (IL-6), and IL-8 protein expression. Apical compression significantly suppressed RV-induced IFN-ß protein from 48 hpi and IFN-λ from 72 hpi in the poor asthma control model. There was a nonsignificant reduction of both IFN-ß and IFN-λ proteins from 48 hpi in the exacerbation model. Despite reductions in antiviral proteins, there was no significant change in viral replication in either model. Compressive stress mimicking bronchoconstriction inhibits antiviral innate immune responses from asthmatic airway epithelial cells when applied before RV infection.NEW & NOTEWORTHY Bronchoconstriction is the main physiological event in asthma, which leads to worsened clinical symptoms and generates mechanical stress within the airways. Virus infection is the primary cause of exacerbations in people with asthma, however, the impact of bronchoconstriction on host antiviral responses and viral replication is unknown. We developed two disease models, in vitro, and found suppressed IFN response from cells following the application of compression and RV-A1 infection. This explains why people with asthma have deficient IFN response.


Subject(s)
Asthma , Picornaviridae Infections , Humans , Rhinovirus , Immunity, Innate , Asthma/metabolism , Antiviral Agents/pharmacology , Epithelial Cells/metabolism
10.
ACS Sustain Chem Eng ; 11(18): 6829-6837, 2023 May 08.
Article in English | MEDLINE | ID: mdl-37180026

ABSTRACT

Reported herein is an entrapment method for enzyme immobilization that does not require the formation of new covalent bonds. Ionic liquid supramolecular gels are formed containing enzymes that can be shaped into gel beads and act as recyclable immobilized biocatalysts. The gel was formed from two components, a hydrophobic phosphonium ionic liquid and a low molecular weight gelator derived from the amino acid phenylalanine. Gel-entrapped lipase from Aneurinibacillus thermoaerophilus was recycled for 10 runs over 3 days without loss of activity and retained activity for at least 150 days. The procedure does not form covalent bonds upon gel formation, which is supramolecular, and no bonds are formed between the enzyme and the solid support.

11.
Histopathology ; 83(1): 91-103, 2023 07.
Article in English | MEDLINE | ID: mdl-36999648

ABSTRACT

AIM: To catalogue and compare the pattern of metastatic disease in germline BRCA1/2 pathogenic mutation carriers and non-carriers with breast, ovarian and prostate cancer from a rapid autopsy programme. METHODS AND RESULTS: The number of metastases in the major body systems and the proportion of participants with metastases were documented in 50 participants (19 germline mutation carriers). Analysis was conducted on the participants' pattern of disease for the different cancers and mutation subgroups. The four commonly affected organ systems were the digestive (liver only) (82%), respiratory (76%), gastrointestinal (65%) and reticuloendothelial (42%). There were significant differences in the pattern of metastatic breast cancer in BRCA1/2 germline carriers compared with non-carriers. Breast cancer carriers had significantly fewer organ systems involved (median n = 3, range = 1-3) compared with non-carriers (median n = 9, range = 1-7) (P = 0.03). BRCA1/2 carriers with ovarian carcinomas had significantly more organ systems with metastatic carcinoma (median n = 10, range = 3-8) than non-carriers (median n = 5, range = 3-5) (P < 0.001). There were no significant differences in the number of involved systems in BRCA2 carriers compared with non-carriers with prostate cancer (P = 1.0). There was an absence of locoregional disease (6.5%) compared with distant disease (93.5%) among the three cancer subtypes (P < 0.001). The majority of metastatic deposits (97%) collected during the autopsy were identified by recent diagnostic imaging. CONCLUSION: Even though a major limitation of this study is that our numbers are small, especially in the breast cancer carrier group, the metastatic patterns of breast and ovarian cancers may be impacted by BRCA1/2 carrier status, suggesting that tumours derived from patients with these mutations use different mechanisms of dissemination. The findings may focus clinical diagnostic imaging for monitoring metastases where whole-body imaging resources are scant.


Subject(s)
Breast Neoplasms , Ovarian Neoplasms , Prostatic Neoplasms , Male , Female , Humans , BRCA1 Protein/genetics , BRCA2 Protein/genetics , Ovarian Neoplasms/genetics , Prostatic Neoplasms/genetics , Autopsy , Genes, BRCA1 , Breast Neoplasms/genetics , Breast Neoplasms/pathology , Mutation , Genetic Predisposition to Disease
12.
Health Place ; 80: 102975, 2023 03.
Article in English | MEDLINE | ID: mdl-36774810

ABSTRACT

The planning and delivery of infrastructure influences how places create health equity. The scholarship on place and health has recently been developed into 'levelling up' principles for equity focussed policy and planning. We conducted a scoping review of the literature on infrastructure through urban regeneration and placemaking interventions. We interrogated the 15 final selected articles for their use of one or more of the five 'levelling' up principles. No article encompassed all five principles. It was most common to find two or three principles in action. Reviewing the articles against the principles allows a deeper explanation of how infrastructure planning practice can positively impact on health equity. We conclude that applying all the principles in standard infrastructure planning practice has great potential for creating places that are positive for health equity.


Subject(s)
Environment , Health Equity , Humans
13.
Am J Physiol Lung Cell Mol Physiol ; 323(4): L495-L502, 2022 Oct 01.
Article in English | MEDLINE | ID: mdl-36041223

ABSTRACT

Primary bronchial epithelial cells (pBECs) obtained from donors have limited proliferation capacity. Recently, conditional reprogramming (CR) technique has overcome this and has provided the potential for extended passaging and subsequent differentiation of cells at air-liquid interface (ALI). However, there has been no donor-specific comparison of cell morphology, baseline gene expression, barrier function, and antiviral responses compared with their "parent" pBECs, especially cells obtained from donors with asthma. We, therefore, collected and differentiated pBECs at ALI from mild donors with asthma (n = 6) for the parent group. The same cells were conditionally reprogrammed and later differentiated at ALI. Barrier function was measured during the differentiation phase. Morphology and baseline gene expression were compared at terminal differentiation. Viral replication kinetics and antiviral responses were assessed following rhinovirus (RV) infection over 96 h. Barrier function during the differentiation phase and cell structural morphology at terminal differentiation appear similar in both parent and CR groups, however, there were elongated cell structures superficial to basal cells and significantly lower FOXJ1 expression in CR group. IFN gene expression was also significantly lower in CR group compared with parent asthma group following RV infection. The CR technique is a beneficial tool to proliferate pBECs over extended passages. Considering lower FOXJ1 expression, viral replication kinetics and antiviral responses, a cautious approach should be taken while choosing CR cells for experiments. In addition, as lab-to-lab cell culture techniques vary, the most appropriate technique must be utilized to best match individual cell functions and morphologies to address specific research questions and experimental reproducibility across the labs.


Subject(s)
Asthma , Picornaviridae Infections , Antiviral Agents/metabolism , Asthma/metabolism , Cells, Cultured , Epithelial Cells/metabolism , Forkhead Transcription Factors/genetics , Forkhead Transcription Factors/metabolism , Humans , Reproducibility of Results , Rhinovirus/physiology
14.
Materials (Basel) ; 15(13)2022 Jun 24.
Article in English | MEDLINE | ID: mdl-35806572

ABSTRACT

The current study focuses on the modeling of two-phase γ-γ' nickel-based superalloys, utilizing multi-scale approaches to simulate and predict the creep behaviors through crystal plasticity finite element (CPFE) platforms. The multi-scale framework links two distinct levels of the spatial spectrum, namely, sub-grain and homogenized scales, capturing the complexity of the system responses as a function of a tractable set of geometric and physical parameters. The model considers two dominant features of γ' morphology and composition. The γ' morphology is simulated using three parameters describing the average size, volume fraction, and shape. The sub-grain level is expressed by a size-dependent, dislocation density-based constitutive model in the CPFE framework with the explicit depiction of γ-γ' morphology as the building block of the homogenized scale. The homogenized scale is developed as an activation energy-based crystal plasticity model reflecting intrinsic composition and morphology effects. The model incorporates the functional configuration of the constitutive parameters characterized over the sub-grain γ-γ' microstructural morphology. The developed homogenized model significantly expedites the computational processes due to the nature of the parameterized representation of the dominant factors while retains reliable accuracy. Anti-Phase Boundary (APB) shearing and, glide-climb dislocation mechanisms are incorporated in the constitutive model which will become active based on the energies associated with the dislocations. The homogenized constitutive model addresses the thermo-mechanical behavior of nickel-based superalloys for an extensive temperature domain and encompasses orientation dependence as well as the loading condition of tension-compression asymmetry aspects. The model is validated for diverse compositions, temperatures, and orientations based on previously reported data of single crystalline nickel-based superalloy.

15.
Commun Biol ; 5(1): 415, 2022 05 04.
Article in English | MEDLINE | ID: mdl-35508632

ABSTRACT

IL-25 is implicated in the pathogenesis of viral asthma exacerbations. However, the effect of IL-25 on antiviral immunity has yet to be elucidated. We observed abundant expression and colocalization of IL-25 and IL-25 receptor at the apical surface of uninfected airway epithelial cells and rhinovirus infection increased IL-25 expression. Analysis of immune transcriptome of rhinovirus-infected differentiated asthmatic bronchial epithelial cells (BECs) treated with an anti-IL-25 monoclonal antibody (LNR125) revealed a re-calibrated response defined by increased type I/III IFN and reduced expression of type-2 immune genes CCL26, IL1RL1 and IL-25 receptor. LNR125 treatment also increased type I/III IFN expression by coronavirus infected BECs. Exogenous IL-25 treatment increased viral load with suppressed innate immunity. In vivo LNR125 treatment reduced IL-25/type 2 cytokine expression and increased IFN-ß expression and reduced lung viral load. We define a new immune-regulatory role for IL-25 that directly inhibits virus induced airway epithelial cell innate anti-viral immunity.


Subject(s)
Asthma , Interleukin-17/immunology , Virus Diseases , Antiviral Agents/pharmacology , Asthma/metabolism , Humans , Immunity, Innate , Rhinovirus
16.
Int J Pharm ; 617: 121586, 2022 Apr 05.
Article in English | MEDLINE | ID: mdl-35181464

ABSTRACT

Nanoparticle-based delivery is a strategy for increasing the therapeutic window of inhaled immunomodulatory drugs that have inflammatory activity. TLR7 agonists are a class of immunomodulators that have been considered for the treatment of virus-induced respiratory diseases. However, due to high immune-stimulatory activity, TLR7 agonists, delivered via direct exposure, generally have a narrow therapeutic window. To address this, we have developed lipid/polymer hybrid nanoparticles (NPs) conjugated with anti-EpCAM monoclonal antibody for targeted delivery of TLR7 agonist (CL264) to airway epithelial cells (AECs)2 - the primary site of respiratory virus infection. These airway epithelial targeting nanoparticles (AEC-NPs)3 showed safety and biocompatibility, and approximately two-fold increased cellular uptake compared to non-targeting NPs. Upon cell entry, AEC-NPs were able to deliver CL264 to cytoplasm and endosomes where TLR7 is located. CL264 delivered by AEC-NPs significantly increased innate immune response through expression of IFN-ß, IFN-λ 2/3 and IFN-stimulated genes and suppressed more than 92% of viral load at 48 h post-infection compared to the drug alone and non-targeting NPs. In conclusion, AEC-NPs exhibited increased cellular uptake leading to enhanced innate immune activation and suppression of viral replication. These findings support the use of AEC-targeting approach for delivering drugs with a narrow therapeutic window.


Subject(s)
Nanoparticles , Toll-Like Receptor 7 , Epithelial Cells , Humans , Immunity, Innate , Virus Replication
17.
Commun Biol ; 5(1): 138, 2022 02 17.
Article in English | MEDLINE | ID: mdl-35177755

ABSTRACT

Diffusion-weighted neuroimaging approaches provide rich evidence for estimating the structural integrity of white matter in vivo, but typically do not assess white matter integrity for connections between two specific regions of the brain. Here, we present a method for deriving tract-specific diffusion statistics, based upon predefined regions of interest. Our approach derives a population distribution using probabilistic tractography, based on the Nathan Kline Institute (NKI) Enhanced Rockland sample. We determine the most likely geometry of a path between two regions and express this as a spatial distribution. We then estimate the average orientation of streamlines traversing this path, at discrete distances along its trajectory, and the fraction of diffusion directed along this orientation for each participant. The resulting participant-wise metrics (tract-specific anisotropy; TSA) can then be used for statistical analysis on any comparable population. Based on this method, we report both negative and positive associations between age and TSA for two networks derived from published meta-analytic studies (the "default mode" and "what-where" networks), along with more moderate sex differences and age-by-sex interactions. The proposed method can be applied to any arbitrary set of brain regions, to estimate both the spatial trajectory and DWI-based anisotropy specific to those regions.


Subject(s)
Brain Mapping/methods , Data Interpretation, Statistical , Diffusion Tensor Imaging/methods , Nerve Net , Animals , Female , Humans , Male
18.
Thorax ; 77(5): 443-451, 2022 05.
Article in English | MEDLINE | ID: mdl-34510013

ABSTRACT

INTRODUCTION: The significance of endoplasmic reticulum (ER) stress in asthma is unclear. Here, we demonstrate that ER stress and the unfolded protein response (UPR) are related to disease severity and inflammatory phenotype. METHODS: Induced sputum (n=47), bronchial lavage (n=23) and endobronchial biopsies (n=40) were collected from participants with asthma with varying disease severity, inflammatory phenotypes and from healthy controls. Markers for ER stress and UPR were assessed. These markers were also assessed in established eosinophilic and neutrophilic murine models of asthma. RESULTS: Our results demonstrate increased ER stress and UPR pathways in asthma and these are related to clinical severity and inflammatory phenotypes. Genes associated with ER protein chaperone (BiP, CANX, CALR), ER-associated protein degradation (EDEM1, DERL1) and ER stress-induced apoptosis (DDIT3, PPP1R15A) were dysregulated in participants with asthma and are associated with impaired lung function (forced expiratory volume in 1 s) and active eosinophilic and neutrophilic inflammation. ER stress genes also displayed a significant correlation with classic Th2 (interleukin-4, IL-4/13) genes, Th17 (IL-17F/CXCL1) genes, proinflammatory (IL-1b, tumour necrosis factor α, IL-8) genes and inflammasome activation (NLRP3) in sputum from asthmatic participants. Mice with allergic airway disease (AAD) and severe steroid insensitive AAD also showed increased ER stress signalling in their lungs. CONCLUSION: Heightened ER stress is associated with severe eosinophilic and neutrophilic inflammation in asthma and may play a crucial role in the pathogenesis of asthma.


Subject(s)
Asthma , Animals , Asthma/metabolism , Endoplasmic Reticulum/metabolism , Endoplasmic Reticulum/pathology , Humans , Inflammation/metabolism , Mice , Neutrophils/metabolism , Signal Transduction , Unfolded Protein Response
19.
Front Physiol ; 12: 690531, 2021.
Article in English | MEDLINE | ID: mdl-34385933

ABSTRACT

Excessive mucus production is a major feature of allergic asthma. Disruption of epithelial junctions by allergens such as house dust mite (HDM) results in the activation of ß-catenin signaling, which has been reported to stimulate goblet cell differentiation. ß-catenin interacts with various co-activators including CREB binding protein (CBP) and p300, thereby regulating the expression of genes involved in cell proliferation and differentiation, respectively. We specifically investigated the role of the ß-catenin/CBP signaling pathway in goblet cell metaplasia in a HDM-induced allergic airway disease model in mice using ICG-001, a small molecule inhibitor that blocks the binding of CBP to ß-catenin. Female 6- 8-week-old BALB/c mice were sensitized to HDM/saline on days 0, 1, and 2, followed by intranasal challenge with HDM/saline with or without subcutaneous ICG-001/vehicle treatment from days 14 to 17, and samples harvested 24 h after the last challenge/treatment. Differential inflammatory cells in bronchoalveolar lavage (BAL) fluid were enumerated. Alcian blue (AB)/Periodic acid-Schiff (PAS) staining was used to identify goblet cells/mucus production, and airway hyperresponsiveness (AHR) was assessed using invasive plethysmography. Exposure to HDM induced airway inflammation, goblet cell metaplasia and increased AHR, with increased airway resistance in response to the non-specific spasmogen methacholine. Inhibition of the ß-catenin/CBP pathway using treatment with ICG-001 significantly attenuated the HDM-induced goblet cell metaplasia and infiltration of macrophages, but had no effect on eosinophils, neutrophils, lymphocytes or AHR. Increased ß-catenin/CBP signaling may promote HDM-induced goblet cell metaplasia in mice.

20.
J Herb Med ; 262021 Apr.
Article in English | MEDLINE | ID: mdl-33585170

ABSTRACT

OBJECTIVES: African potato (hypoxis hemerocallidea) is used against HIV to enhance immune-function, although no studies have evaluated its use in HIV infected individuals on combination antiretroviral therapy. The study aimed to evaluate the acute effects of orally administered hypoxoside, a constituent of African potato, on the hepatic and renal function in HIV infected individuals on tenofovir disoproxil fumarate/ lamivudine/ efavirenz regimen. METHODS: This was an open-label, two-period, fixed-sequence, pre-post test study, pilot design. Ethical approval was obtained from Medical Research Council of Zimbabwe (MRCZ A/2045) and Medicines Control Authority of Zimbabwe (MCAZ CT134/2016). Blood samples were collected before and after administration of African potato tablets. Tablets were administered orally once daily at 15mg/ kg hypoxoside for 10 days. Hepatic function tests (ALT, AST, ALP, GGT, albumin, total/ direct bilirubin); renal function tests (eGFR, blood urea nitrogen, creatinine), serum electrolytes (sodium, potassium, chloride) were assayed. STATA was used for statistical analysis. RESULTS: Twenty-six participants were enrolled (85% female). Median age (range) was 43 (28-52) years. Most had overweight Body Mass Index (46%) and were married (54%). No statistical difference was noted during hypoxoside for AST/ ALT/ ALP/ GGT/ albumin/ bilirubin. There were no changes in creatinine/ eGFR/ electrolytes. A mean significant increase in total protein (p=0.04) and decrease in blood urea nitrogen (p=0.04) were noted. CONCLUSION: Short-term exposure to hypoxoside from African potato appeared safe and was not associated with clinically significant changes in hepatic, renal function tests/electrolytes. There is further need to evaluate extent of systemic exposure during long-term use in a larger population.

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