An individualised 3D computational flow and particle model to predict the deposition of inhaled medicines - A case study using a nebuliser

BACKGROUND AND OBJECTIVE

Drug inhalation is generally accepted as the preferred administration method for treating respiratory diseases. To achieve effective inhaled drug delivery for an individual, it is necessary to use an interdisciplinary approach that can cope with inter-individual differences. The paper aims to present an individualised pulmonary drug deposition model based on Computational Fluid and Particle Dynamics simulations within a time frame acceptable for clinical use.

METHODS

We propose a model that can analyse the inhaled drug delivery efficiency based on the patient's airway geometry as well as breathing pattern, which has the potential to also serve as a tool for a sub-regional diagnosis of respiratory diseases. The particle properties and size distribution are taken for the case of drug inhalation by using nebulisers, as they are independent of the patient's breathing pattern. Finally, the inhaled drug doses that reach the deep airways of different lobe regions of the patient are studied.

RESULTS

The numerical accuracy of the proposed model is verified by comparison with experimental results. The difference in total drug deposition fractions between the simulation and experimental results is smaller than 4.44% and 1.43% for flow rates of 60 l/min and 15 l/min, respectively. A case study involving a COVID-19 patient is conducted to illustrate the potential clinical use of the model. The study analyses the drug deposition fractions in relation to the breathing pattern, aerosol size distribution, and different lobe regions.

CONCLUSIONS

The entire process of the proposed model can be completed within 48 h, allowing an evaluation of the deposition of the inhaled drug in an individual patient's lung within a time frame acceptable for clinical use. Achieving a 48-hour time window for a single evaluation of patient-specific drug delivery enables the physician to monitor the patient's changing conditions and potentially adjust the drug administration accordingly. Furthermore, we show that the proposed methodology also offers a possibility to be extended to a detection approach for some respiratory diseases.

[Study on evaluation method of circular small shadow profusion in chest CT reconstruction images of pneumoconiosis]

Objective: To select chest CT image patterns for the diagnosis of pneumoconiosis and establish a method for determining the profusion of circular small shadows in chest CT. Methods: In April 2021, 66 cases of occupational pneumoconiosis patients with digital radiography (DR) chest radiographs and chest CT imaging data with circular small shadow as the main manifestations were selected as the study objects. 1.5 mm and 5 mm chest CT axial images, 1 mm and 5 mm chest CT coronal multi-plane recombination (MPR) images, and 5 mm chest CT coronal maximum intensity projection (MIP) images were used to observe the different characteristics of pneumoconiosis patients, and were compared and analyzed with DR chest radiographs to establish the experimental chest CT standards. The consistency of the profusion results between the experimental chest CT standards and GBZ 70-2015 Diagnosis of Occupational Pneumoconiosis was verified. Results: All the 66 objects were male, including 33 cases of stage Ⅰ pneumoconiosis, 17 cases of stage Ⅱ pneumoconiosis and 16 cases of stage Ⅲ pneumoconiosis. By observing five chest CT images of 66 objects, we found that chest CT images of different modes could clearly display and identify abnormal images such as small circular shadow, large shadow, small shadow aggregation, honeycomb glass shadow, flake glass shadow, uniform low-profusion glass shadow, mesh glass shadow, cable shadow, linear shadow, subpleural spinous shadow, subpleural nodules, various kinds of emphysema and lung texture distortion and fracture. Small shadow aggregation was usually accompanied by the appearance of large shadow. The vascular shadows in 5 mm CT images had good ductility, and small nodules were easy to distinguish. The coronal MIP image of 5 mm chest CT used edge enhancement technology, which was prone to small shadow fusion and fibrotic shadow fusion. The coronal MPR image of 5 mm chest CT was highly consistent with the DR chest radiographs in terms of the integrity of film reading. GBZ 70-2015 standard was used to compare the profusion of DR chest radiographs and 5 mm chest CT coronal MPR images of 66 objects, and the consistency test Kappa=0.64. GBZ 70-2015 standard and experimental chest CT standard were used to compare the profusion results of DR chest radiographs and 5 mm chest CT coronal MPR images of 66 objects, respectively, and the consistency test Kappa=0.80, with high consistency. Conclusion: 5 mm coronal MPR image is suitable for chest CT imaging in the diagnosis of pneumoconiosis. Following the selection path and method of GBZ 70-2015 profusion criterion, the established experimental chest CT standard in determining the profusion of small circular shadows in 5 mm coronal MPR images of chest CT with pneumoconiosis has a high consistency with GBZ 70-2015 standard.

Amino acids as stabilizers for lysozyme during the spray-drying process and storage

Amino acids (AAs) have been used as excipients in protein formulations both in solid and liquid state products due to their stabilizing effect. However, the mechanisms by which they can stabilize a protein have not been fully elucidated yet. The purpose of this study was to investigate the effect of AAs with distinct physicochemical properties on the stability of a model protein (lysozyme, LZM) during the spray-drying process and subsequent storage. Molecular descriptor based multivariate data analysis was used to select distinct AAs from the group of 20 natural AAs. Then, LZM and the five selected AAs (1:1 wt ratio) were spray-dried (SD). The solid form, residual moisture content (RMC), hygroscopicity, morphology, secondary/tertiary structure and enzymatic activity of LZM were evaluated before and after storage under 40 °C/75 % RH for 30 days. Arginine (Arg), leucine (Leu), glycine (Gly), tryptophan (Trp), aspartic acid (Asp) were selected because of their distinct properties by using principal component analysis (PCA). The SD LZM powders containing Arg, Trp, or Asp were amorphous, while SD LZM powders containing Leu or Gly were crystalline. Recrystallization of Arg, Trp, Asp and polymorph transition of Gly were observed after the storage under accelerated conditions. The morphologies of the SD particles vary upon the different AAs formulated with LZM, implying different drying kinetics of the five model systems. A tertiary structural change of LZM was observed in the SD powder containing Arg, while a decrease in the enzymatic activity of LZM was observed in the powders containing Arg or Asp after the storage. This can be attributed to the extremely basic and acidic conditions that Arg and Asp create, respectively. This study suggests that when AAs are used as stabilizers instead of traditional disaccharides, not only do classic vitrification theory and water replacement theory play a role, but the microenvironmental pH conditions created by basic or acidic AAs in the starting solution or during the storage of solid matter are also crucial for the stability of SD protein products.

[A transcriptomic analysis of correlation between mitochondrial function and energy metabolism remodeling in mice with myocardial fibrosis following myocardial infarction]

OBJECTIVE

To investigate the changes of mitochondrial respiratory function during myocardial fibrosis in mice with myocardial infarction (MI) and its correlation with the increase of glycolytic flux.

METHODS

Forty C57BL/6N mice were randomized into two equal groups to receive sham operation or ligation of the left anterior descending coronary artery to induce acute MI. At 28 days after the operation, 5 mice from each group were euthanized and left ventricular tissue samples were collected for transcriptomic sequencing. FPKM method was used to calculate gene expression levels to identify the differentially expressed genes (DEGs) in MI mice, which were analyzed using GO and KEGG databases to determine the pathways affecting the disease process. Heat maps were drawn to show the differential expressions of the pathways and the related genes in the enrichment analysis. In primary cultures of neonatal mouse cardiac fibroblasts (CFs), the changes in mitochondrial respiration and glycolysis levels in response to treatment with the pro-fibrotic agonist TGF-β1 were analyzed using Seahorse experiment.

RESULTS

The mouse models of MI showed significantly increased diastolic and systolic left ventricular diameter (P < 0.05) and decreased left ventricular ejection fraction (P < 0.0001). A total of 124 up-regulated and 106 down-regulated DEGs were identified in the myocardial tissues of MI mice, and GO and KEGG enrichment analysis showed that these DEGs were significantly enriched in fatty acid metabolism, organelles and other metabolic pathways and in the mitochondria. Heat maps revealed fatty acid beta oxidation, mitochondrial dysfunction and increased glycolysis levels in MI mice. In the primary culture of CFs, treatment with TGF-β1 significantly reduced the basal and maximum respiratory levels and increased the basal and maximum glycolysis levels (P < 0.0001).

CONCLUSION

During myocardial fibrosis, energy metabolism remodeling occurs in the CFs, manifested by lowered mitochondrial function and increased energy generation through glycolysis.

Co-spray dried inhalable composite powders of ciprofloxacin and alginate oligosaccharide as anti-biofilm therapy

The treatment of chronic respiratory infections caused by biofilm formation are extremely challenging owing to poor drug penetration into the complex biofilm structure and high drug resistance. Local delivery of an antibiotic together with a non-antibiotic adjuvant to the lungs could often enhance the therapeutic responses by targeting different bacterial growth pathways and minimizing drug resistance. In this study, we designed new inhalable dry powders containing ciprofloxacin (CIP) and OligoG (Oli, a low-molecular-weight alginate oligosaccharide impairing the mucoid biofilms by interacting with their cationic ions) to combat respiratory bacterial biofilm infections. The resulting powders were characterized with respect to their morphology, solid-state property, surface chemistry, moisture sorption behavior, and dissolution rate. The aerosol performance and storage stability of the dry powders were also evaluated. The results showed that inhalable dry powders composed of CIP and Oli could be readily accomplished via the wet milling and spray drying process. Upon the storage under 20 ± 2 °C/20 ± 2 % relative humidity (RH) for one month, there was no significant change in the in vitro aerosol performances of the dry powders. In contrast, the dry powders became non-inhalable following the storage at 20 ± 2 °C/53 ± 2 % RH for one month due to the hygroscopic nature of Oli, which could be largely prevented by incorporation of leucine. Collectively, this study suggests that the newly developed co-spray-dried powders composed of CIP and Oli might represent a promising and alternative treatment strategy against respiratory bacterial biofilm infections.

Lipoprotein(a) is associated with recurrent cardiovascular events in patients with coronary artery disease and prediabetes or diabetes

PURPOSE

Elevated lipoprotein(a) [Lp(a)] and diabetes mellitus (DM) are both associated with adverse events in high-risk patients with established coronary artery disease (CAD). Currently, the association between Lp(a) levels and recurrent cardiovascular (CV) events (CVEs) remained undetermined in patients with different glucose status. Therefore, this study aimed to investigate the prognostic significance of Lp(a) levels for recurrent CVEs in high-risk CAD patients who suffered from first CVEs according to different glycemic metabolism.

METHODS

We recruited 5257 consecutive patients with prior CVEs and followed up for recurrent CVEs, including CV death, non-fatal myocardial infarction (MI), and non-fatal stroke. Patients were assigned to low, medium, and high groups according to Lp(a) levels and further stratified by glucose status.

RESULTS

During a median 37-month follow-up, 225 (4.28%) recurrent CVEs occurred. High Lp(a) was independently associated with recurrent CVEs [adjusted Hazard Ratio (HR), 1.57; 95% confidence interval (CI) 1.12-2.19; P = 0.008]. When participants were classified according to Lp(a) levels and glycemic status, high Lp(a) levels were associated with an increased risk of recurrent CVEs in pre-DM (adjusted HR, 2.96; 95% CI 1.24-7.05; P = 0.014). Meanwhile, medium and high Lp(a) levels were both associated with an increased risk for recurrent CVEs in DM (adjusted HR, 3.09; 95% CI 1.30-7.34; P = 0.010 and adjusted HR, 3.13, 95% CI 1.30-7.53; P = 0.011, respectively).

CONCLUSIONS

This study demonstrated that elevated Lp(a) levels were associated with an increased recurrent CVE risk in patients with CAD, particularly among those with pre-DM and DM, indicating that Lp(a) may provide incremental value in risk stratification in this population.

Sialic Acid Conjugate-Modified Cationic Liposomal Paclitaxel for Targeted Therapy of Lung Metastasis in Breast Cancer: What a Difference the Cation Content Makes

Cationic lipids play a pivotal role in developing novel drug delivery systems for diverse biomedical applications, owing to the success of mRNA vaccines against COVID-19 and the Phase III antitumor agent EndoTAG-1. However, the therapeutic potential of these positively charged liposomes is limited by dose-dependent toxicity. While an increased content of cationic lipids in the formulation can enhance the uptake and cytotoxicity toward tumor-associated cells, it is crucial to balance these advantages with the associated toxic side effects. In this work, we synthesized the cationic lipid HC-Y-2 and incorporated it into sialic acid (SA)-modified cationic liposomes loaded with paclitaxel to target tumor-associated immune cells efficiently. The SA-modified cationic liposomes exhibited enhanced binding affinity toward both RAW264.7 cells and 4T1 tumor cells in vitro due to the increased ratios of cationic HC-Y-2 content while effectively inhibiting 4T1 cell lung metastasis in vivo. By leveraging electrostatic forces and ligand-receptor interactions, the SA-modified cationic liposomes specifically target malignant tumor-associated immune cells such as tumor-associated macrophages (TAMs), reduce the proportion of cationic lipids in the formulation, and achieve dual objectives: high cellular uptake and potent antitumor efficacy. These findings highlight the potential advantages of this innovative approach utilizing cationic liposomes.

[A multicenter prospective study on early identification of refractory Mycoplasma pneumoniae pneumonia in children]

Objective: To explore potential predictors of refractory Mycoplasma pneumoniae pneumonia (RMPP) in early stage. Methods: The prospective multicenter study was conducted in Zhejiang, China from May 1st, 2019 to January 31st, 2020. A total of 1 428 patients with fever >48 hours to <120 hours were studied. Their clinical data and oral pharyngeal swab samples were collected; Mycoplasma pneumoniae DNA in pharyngeal swab specimens was detected. Patients with positive Mycoplasma pneumoniae DNA results underwent a series of tests, including chest X-ray, complete blood count, C-reactive protein, lactate dehydrogenase (LDH), and procalcitonin. According to the occurrence of RMPP, the patients were divided into two groups, RMPP group and general Mycoplasma pneumoniae pneumonia (GMPP) group. Measurement data between the 2 groups were compared using Mann-Whitney U test. Logistic regression analyses were used to examine the associations between clinical data and RMPP. Receiver operating characteristic (ROC) curves were used to analyse the power of the markers for predicting RMPP. Results: A total of 1 428 patients finished the study, with 801 boys and 627 girls, aged 4.3 (2.7, 6.3) years. Mycoplasma pneumoniae DNA was positive in 534 cases (37.4%), of whom 446 cases (83.5%) were diagnosed with Mycoplasma pneumoniae pneumonia, including 251 boys and 195 girls, aged 5.2 (3.3, 6.9) years. Macrolides-resistant variation was positive in 410 cases (91.9%). Fifty-five cases were with RMPP, 391 cases with GMPP. The peak body temperature before the first visit and LDH levels in RMPP patients were higher than that in GMPP patients (39.6 (39.1, 40.0) vs. 39.2 (38.9, 39.7) ℃, 333 (279, 392) vs. 311 (259, 359) U/L, both P<0.05). Logistic regression showed the prediction probability π=exp (-29.7+0.667×Peak body temperature (℃)+0.004×LDH (U/L))/(1+exp (-29.7+0.667×Peak body temperature (℃)+0.004 × LDH (U/L))), the cut-off value to predict RMPP was 0.12, with a consensus of probability forecast of 0.89, sensitivity of 0.89, and specificity of 0.67; and the area under ROC curve was 0.682 (95%CI 0.593-0.771, P<0.01). Conclusion: In MPP patients with fever over 48 to <120 hours, a prediction probability π of RMPP can be calculated based on the peak body temperature and LDH level before the first visit, which can facilitate early identification of RMPP.

Diagnostic value of dynamic contrast enhancement combined with conventional MRI in differentiating benign and malignant lacrimal gland epithelial tumours

AIM

To establish the diagnostic value of the quantitative parameters of dynamic contrast-enhanced (DCE) magnetic resonance imaging (MRI) combined with conventional MRI in differentiating of benign and malignant lacrimal gland epithelial tumours.

MATERIALS AND METHODS

A retrospective analysis of primary lacrimal gland epithelial tumours confirmed by histopathology was conducted. Conventional MRI features and DCE-MRI quantitative parameters were collected and subjected to analysis. The diagnostic value was evaluated using receiver operating characteristic (ROC) curve analysis.

RESULTS

A total of 53 patients were enrolled of which 29 had malignant, whereas 24 had benign tumours. Conventional MRI revealed statistically significant differences between benign and malignant tumours regarding maximum tumour diameter, posterior margin characteristic, bone destruction, and erosion. The Ktrans and Kep values obtained by DCE-MRI were higher in malignant than in benign tumours, with a statistically significant (p<0.001 and p=0.022). A type I time-signal intensity (TIC) curve was more frequent in benign tumours, whereas a type II TIC curve was prevalent in malignant tumours (p=0.001). ROC analysis showed that Ktrans had the best diagnostic value of the DCE-MRI parameters (area under the ROC curve [AUC] of 0.822, 75.9% sensitivity, and 83.3% specificity, p<0.001). The combination of conventional MRI and DCE-MRI factors had the best diagnostic value and balanced sensitivity and specificity (AUC of 0.948, 93.1% sensitivity, and 91.7% specificity, p<0.001).

CONCLUSIONS

The present findings indicate that the combination of quantitative parameters of DCE-MRI and image characteristics of conventional MRI have a high diagnostic value for the diagnosis of benign and malignant lacrimal gland epithelial tumours.

Differentiation of Crohn's disease, ulcerative colitis, and intestinal tuberculosis by dual-layer spectral detector CT enterography

AIM

To investigate the value of radiological features and energy spectrum quantitative parameters in the differential diagnosis of Crohn's disease (CD), ulcerative colitis (UC), and intestinal tuberculosis (ITB) by dual-layer spectral detector computed tomography (CT) enterography (CTE).

MATERIALS AND METHODS

Clinical and CTE data were collected from 182 patients with CD, 29 with UC, and 51 with ITB. CT images were obtained at the enteric phases and portal phases. The quantitative energy spectrum parameters were iodine density (ID), normalised ID (NID), virtual non-contrast (VNC) value, and effective atomic number (Z-eff). The area under curve (AUC) of the receiver operating characteristic curve (ROC) was calculated.

RESULTS

The vascular comb sign (p=0.009) and enlarged lymph nodes (p=0.001) were more common in patients with CD than UC or ITB. In the differentiation of moderate-severe active CD from UC, enteric phase NID (AUC, 0.938; p<0.001) and portal phase Z-eff (AUC, 0.925; p<0.001) had the highest accuracy, which were compared separately. In the differentiation of moderate-severe active CD from ITB, enteric phase NID (AUC, 0.906; p<0.001) and portal phase Z-eff (AUC, 0.947; p<0.001) had the highest accuracy; however, the AUC value was highest when the four parameters are combined (AUC, 0.989; p<0.001; AUC, 0.986; p<0.001; AUC, 0.936; p<0.001; and AUC, 0.986; p<0.001).

CONCLUSION

The present study shows that the combined strategies of four parameters have higher sensitivity and specificity in differentiating CD, UC, and ITB, and may play a key role in guiding treatment.

Global burden and inequality of maternal and neonatal disorders: based on data from the 2019 Global Burden of Disease study

BACKGROUND

Maternal and neonatal disorders account for substantial health loss across the lifespan from early childhood. These problems may be related to health inequality.

AIM

To provide evidence for improvement in health policies regarding maternal and neonatal disorder inequity.

DESIGN

This was a population-based cross-sectional study based on 2019 Global Burden of Disease data.

METHODS

Annual cases and age-standardized rates (ASRs) of incidence, prevalence, death, and disability-adjusted life-years (DALYs) in maternal and neonatal disorders between 1990 and 2019 were collected from the 2019 Global Burden of Disease study. Concentration curves and concentration indices were used to summarize the degree of socioeconomic-related inequality.

RESULTS

For maternal disorders, the global ASRs of incidence, prevalence, death and DALYs were 2889.4 (95% uncertainty interval (UI), 2562.9-3251.9), 502.9 (95% UI 418.7-598.0), 5.0 (95% UI 4.4-5.8) and 324.9 (95% UI 284.0-369.1) per 100 000 women in 2019, respectively. The ASRs of maternal disorders were all obviously reduced and remained pro-poor from 1990 to 2019. In neonatal disorders, the global ASRs of incidence, prevalence, death and DALYs were 363.3 (95% UI 334.6-396.8), 1239.8 (95% UI 1142.1-1356.7), 29.1 (95% UI 24.8-34.5) and 2828.3 (95% UI 2441.6-3329.6) per 100 000 people in 2019, respectively. The global ASRs of incidence, death and DALYs in neonatal disorders have remained pro-poor. However, the socioeconomic-related fairness in the ASR of neonatal disorder prevalence is being levelled.

CONCLUSIONS

The global burden of maternal and neonatal disorders has remained high, and socioeconomic-related inequality (pro-poor) tended not to change between 1990 and 2019.

Long-acting inhaled medicines: Present and future

Inhaled medicines continue to be an essential part of treatment for respiratory diseases such as asthma, chronic obstructive pulmonary disease, and cystic fibrosis. In addition, inhalation technology, which is an active area of research and innovation to deliver medications via the lung to the bloodstream, offers potential advantages such as rapid onset of action, enhanced bioavailability, and reduced side effects for local treatments. Certain inhaled macromolecules and particles can also end up in different organs via lymphatic transport from the respiratory epithelium. While the majority of research on inhaled medicines is focused on the delivery technology, particle engineering, combination therapies, innovations in inhaler devices, and digital health technologies, researchers are also exploring new pharmaceutical technologies and strategies to prolong the duration of action of inhaled drugs. This is because, in contrast to most inhaled medicines that exert a rapid onset and short duration of action, long-acting inhaled medicines (LAIM) improve not only the patient compliance by reducing the dosing frequency, but also the effectiveness and convenience of inhaled therapies to better manage patients' conditions. This paper reviews the advances in LAIM, the pharmaceutical technologies and strategies for developing LAIM, and emerging new inhaled modalities that possess a long-acting nature and potential in the treatment and prevention of various diseases. The challenges in the development of the future LAIM are also discussed where active research and innovations are taking place.

Investigating the Impact of Tea Consumption on Cognitive Function and Exploring Tea-Genetic Interactions in Older Adults Aged 65-105 Years: Findings from the 2002-2018 CLHLS Data

BACKGROUND

As the global population ages, cognitive impairment (CI) becomes more prevalent. Tea has been one of the most popular drinks in the world. Several studies have demonstrated that tea consumption has an impact on cognitive function.

OBJECTIVE

This study aims to examine the association between tea consumption and cognitive function and explore the potential effect of genetics on the relationship between tea consumption and CI risk in older adults.

DESIGN

This is a prospective longitudinal study using data from the Chinese Longitudinal Healthy Longevity Survey (CLHLS).

SETTING

Six waves of data from CLHLS containing 76,270 subjects were analyzed. Generalized estimation equations (GEE) with a logit link function were adopted to estimate the effect of tea consumption on CI risk from a cross-sectional and longitudinal perspective.

PARTICIPANTS

A population-based cohort of adults aged 65-105 years.

MEASUREMENTS

The frequency and type of tea consumption were obtained by questionnaires. CI was measured based on MMSE. Polygenic risk was measured using the polygenic score approach described by the International Schizophrenia.

RESULTS

The results showed that drinking green tea had a better protective effect on cognitive function than other types of tea, the incidence of CI gradually decreased with the increase of tea consumption frequency, and men were more likely to benefit from tea consumption. Additionally, we also found a significant interaction between tea consumption and genetic risk, measured by polygenic risk score (PRS).

CONCLUSIONS

Based on current research evidence, tea consumption, may be a simple and important measure for CI prevention.

Estrogen as a guardian of auditory health: Tsp1-CD47 axis regulation and noise-induced hearing loss

OBJECTIVES

This study aimed to analyze the role of estrogen in noise-induced hearing loss (NIHL) and uncover underlying mechanisms.

METHODS

An ovariectomized Sprague-Dawley rat model (OVX) was constructed to investigate the hearing threshold and auditory latency before and after noise exposure using the auditory brainstem response (ABR) test. The morphological changes were assessed using immunofluorescence, scanning electron microscopy and transmission electron microscopy. Proteomics and bioinformatics were used to analyze the mechanism. The findings were further verified through western blot and Luminex liquid suspension chip technology.

RESULTS

After noise exposure, OVX rats exhibited substantially elevated hearing thresholds. A conspicuous delay in ABR wave I latency was observed, alongside increased loss of outer hair cells, severe collapse of stereocilia and pronounced deformation of the epidermal plate. Accordingly, OVX rats with estrogen supplementation exhibited tolerance to NIHL. Additionally, a remarkable upregulation of the thrombospondin 1 (Tsp1)-CD47 axis in OVX rats was discovered and verified.

CONCLUSIONS

OVX rats were more susceptible to NIHL, and the protective effect of estrogen was achieved through regulation of the Tsp1-CD47 axis. This study presents a novel mechanism through which estrogen regulates NIHL and offers a potential intervention strategy for the clinical treatment of NIHL.

Inhaled RNA drugs to treat lung diseases: Disease-related cells and nano-bio interactions

In recent years, RNA-based therapies have gained much attention as biomedicines due to their remarkable therapeutic effects with high specificity and potency. Lung diseases offer a variety of currently undruggable but attractive targets that could potentially be treated with RNA drugs. Inhaled RNA drugs for the treatment of lung diseases, including asthma, chronic obstructive pulmonary disease, cystic fibrosis, and acute respiratory distress syndrome, have attracted more and more attention. A variety of novel nanoformulations have been designed and attempted for the delivery of RNA drugs to the lung via inhalation. However, the delivery of RNA drugs via inhalation poses several challenges. It includes protection of the stability of RNA molecules, overcoming biological barriers such as mucus and cell membrane to the delivery of RNA molecules to the targeted cytoplasm, escaping endosomal entrapment, and circumventing unwanted immune response etc. To address these challenges, ongoing researches focus on developing innovative nanoparticles to enhance the stability of RNA molecules, improve cellular targeting, enhance cellular uptake and endosomal escape to achieve precise delivery of RNA drugs to the intended lung cells while avoiding unwanted nano-bio interactions and off-target effects. The present review first addresses the pathologic hallmarks of different lung diseases, disease-related cell types in the lung, and promising therapeutic targets in these lung cells. Subsequently we highlight the importance of the nano-bio interactions in the lung that need to be addressed to realize disease-related cell-specific delivery of inhaled RNA drugs. This is followed by a review on the physical and chemical characteristics of inhaled nanoformulations that influence the nano-bio interactions with a focus on surface functionalization. Finally, the challenges in the development of inhaled nanomedicines and some key aspects that need to be considered in the development of future inhaled RNA drugs are discussed.

Identification and adaptive evolution analysis of glutaredoxin genes in Populus spp

Glutaredoxin (GRX) is a class of small redox proteins widely involved in cellular redox homeostasis and the regulation of various cellular processes. The role of GRX gene in the differentiation of Populus spp. is rarely reported. We compared the similarities and differences of GRX genes among four sections of poplar using bioinformatics, corrected the annotations of some GRX genes, and focused on analysing their transcript profiling and adaptive evolution in Populus spp. A total of 219 GRX genes were identified in four sections of poplar, among which annotations for 13 genes were corrected. Differences in GRX genes were found between sect. Turanga, represented by P. euphratica, and other poplar sections. Most notably, P. euphratica had the smallest number of duplication events for GRX genes (n = 9) and no tandem duplications, whereas there were >25 duplication events for all other poplars. Furthermore, we detected 18 pairs of GRX genes under positive selection pressure in various sections of poplar, and identified two groups of GRX genes in the Salicaceae that potentially underwent positive selection. Expression profiling results showed that the PtrGRX34 and its orthologous genes were upregulated under stress treatments. In summary, the GRX gene family underwent expansion during poplar differentiation, and some genes underwent rapid evolution during this process, which may be beneficial for Populus spp. to adapt to environmental changes. This study may provide more insights into the molecular mechanisms of Populus spp. adaptation to environmental changes and the adaptive evolution of GRX genes.

Unleashing the healing potential: Exploring next-generation regenerative protein nanoscaffolds for burn wound recovery

Burn injury is a serious public health problem and scientists are continuously aiming to develop promising biomimetic dressings for effective burn wound management. In this study, a greater efficacy in burn wound healing and the associated mechanisms of α-lactalbumin (ALA) based electrospun nanofibrous scaffolds (ENs) as compared to other regenerative protein scaffolds were established. Bovine serum albumin (BSA), collagen type I (COL), lysozyme (LZM) and ALA were separately blended with poly(ε-caprolactone) (PCL) to fabricate four different composite ENs (LZM/PCL, BSA/PCL, COL/PCL and ALA/PCL ENs). The hydrophilic composite scaffolds exhibited an enhanced wettability and variable mechanical properties. The ALA/PCL ENs demonstrated higher levels of fibroblast proliferation and adhesion than the other composite ENs. As compared to PCL ENs and other composite scaffolds, the ALA/PCL ENs also promoted a better maturity of the regenerative skin tissues and showed a comparable wound healing effect to Collagen spongeⓇ on third-degree burn model. The enhanced wound healing activity of ALA/PCL ENs compared to other ENs could be attributed to their ability to promote serotonin production at wound sites. Collectively, this investigation demonstrated that ALA is a unique protein with a greater potential for burn wound healing as compared to other regenerative proteins when loaded in the nanofibrous scaffolds.

Hypofractionated Radiotherapy with Prolonged Inter-Fraction Interval (Hypo-Slow RT) to Facilitate Immune Priming of Tumor

PURPOSE/OBJECTIVE(S)

Daily fractionated radiotherapy may pose constant stress for immune activation. A mouse model was built to explore whether hypofractionated radiotherapy with prolonged inter-fraction interval (Hypo-Slow Radiotherapy, HSRT) may enable better immune-priming of tumor than daily radiotherapy.

MATERIALS/METHODS

A subcutaneous MC38 murine colon cancer mouse model was irradiated at different radiation regimens. The impact of inter-fraction interval and dose per fraction on tumor control, immune mobilization, and synergistic effect with anti-PD-1 immunotherapy was explored. Immune activation was assessed by analyzing CD4+ and CD8+ T cells from peripheral blood, and intratumoral CD4+ and CD8+ T cells by flow cytometry; both were sampled three days after the completion of scheduled irradiation.

RESULTS

In a fixed dose per fraction experiment, the 6×5Gy QOD and 6×5Gy QD irradiation schemes resulted in identical tumor control, while the 6×5Gy BIW scheme led to tumor progression; moreover, both QOD and BIW regimens showed ability to activate immune response whereas QD regimen did not. In a fixed biological equivalent dose (BED) experiment, the comparison of different regimens with increased dose per fraction and prolonged inter-fraction interval showed that 12×3Gy QD regimen, HSRT regimens, including 6×5Gy QOD, 4×7Gy BIW, and 2×11Gy QW, led to identical tumor control. Importantly, all HSRT regimens showed significant mobilization of host immunity whereas 12×3Gy QD did not. Both peripheral and intratumor CD4+ and CD8+ cell increase with increased inter-fraction interval and dose per fraction. Finally, all HSRT regimens combined with anti-PD-1 immunotherapy showed enhanced tumor growth delay than any single treatment while 12×3Gy QD regimen did not.

CONCLUSION

This pre-clinical model demonstrated that conventional daily fractionated radiotherapy is not beneficial for host immune activation against tumor. Preliminary results suggested that prolonged inter-fraction interval with increased dose per fraction may be an optional strategy to balance the tumor control and immune activation.

Establishing a Chinese older hip fracture registry for older patients: a Delphi study to define the focus and key variables for this registry

A national hip fracture registry does not yet exist in China. This is the first to recommend a core variable set for the establishment of a Chinese national hip fracture registry. Thousands of Chinese hospitals will build on this and improve the quality of management for older hip fracture patients. The rapidly ageing population of China already experiences over half a million hip fractures every year. Many countries have developed national hip fracture registries to improve the quality of hip fracture management, but such a registry does not exist in China. The study is aimed at determining the core variables of a national hip fracture registry for older hip fracture patients in China. A rapid literature review was conducted to develop a preliminary pool of variables from existing global hip fracture registries. Two rounds of an e-Delphi survey were conducted with experts. The e-Delphi survey used a Likert 5-point scale and boundary value analysis to filter the preliminary pool of variables. The list of core variables was finalised following an online consensus meeting with the experts. Thirty-one experts participated. Most of the experts have senior titles and have worked in a corresponding area for more than 15 years. The response rate of the e-Delphi was 100% for both rounds. The preliminary pool of 89 variables was established after reviewing 13 national hip fracture registries. With two rounds of the e-Delphi and the expert consensus meeting, 86 core variables were recommended for inclusion in the registry. This study is the first to recommend a core variable set for the establishment of a Chinese national hip fracture registry. The further development of a registry to routinely collect data from thousands of hospitals will build on this work and improve the quality of management for older hip fracture patients in China.

LINC00921 Diminishes Lung Cancer Radiosensitivity by Bestabilizing NUDT21 and Driving Aberrant MED23 Alternative Polyadenylation

PURPOSE/OBJECTIVE(S)

Alternative polyadenylation (APA) plays a major role in controlling transcriptome diversity and therapeutic resistance of cancers. However, long-noncoding RNAs (lncRNAs) involved in pathological APA remain poorly defined. Here, we functionally identified a MED13L/P300-induced oncogenic lncRNA, LINC00921, diminished lung cancer radiosensitivity by destabilizing NUDT21 and driving aberrant MED23 alternative polyadenylation.

MATERIALS/METHODS

ChIP-seq screening, RNA-seq and real-time PCR were used to identified LINC00921 in NSCLC. We performed RNA pulldown, RIP-qPCR, western blotting and Co-immunoprecipitation to investigate the function of LINC00921, which induced destabilization of NUDT21 and promoted 3' UTR shortening of MED23 via APA.

RESULTS

Through H3K27ac ChIP-seq screening, we functionally characterize LINC00921, a MED13L/P300-induced oncogenic lncRNA, required for global regulation of APA in non-small-cell lung cancer (NSCLC). LINC00921 shows significant potential for reducing radiosensitivity of NSCLC and high LINC00921 levels were associated with poor prognosis for NSCLC patients treated with radiotherapy. Mechanistically, LINC00921 directly interacts withNUDT21 via binding to its RNA-binding motif-2. LINC00921 controls NUDT21 stability via facilitating binding of NUDT21 with its newly identified E3 ligase TRIP12. Intriguingly, 3'UTR APA profiles reveal that LINC00921-induced destabilization of NUDT21 decreases the percentage of distal polyadenylation sites (PAS) usage index, resulting in the 3' UTR shortening of MED23 mRNA, which, in turn, leads to elevated MED23 protein levels in cancer cells. MED23 further increases nuclear translocation of β-catenin, and, thereby, activates expression of multiple β-Catenin/TCF/LEF-regulated core oncogenes (c-Myc, CCND1, and BMP4).

CONCLUSION

Taken together, our data revealed a novel model that integrates a lncRNA into regulation of malignant APA, radiotherapy resistance and NSCLC progression. These findings highlight the importance of functionally annotating lncRNAs controlling APA and unlock the clinical potential of novel therapeutics for advanced NSCLC.

20(R)-ginsenoside Rg3-loaded polyurethane/marine polysaccharide based nanofiber dressings improved burn wound healing potentials

The management of deep burn injuries is extremely challenging, ascribed to their delayed wound healing rate, susceptibility for bacterial infections, pain, and increased risk of hypertrophic scarring. In our current investigation, a series of composite nanofiber dressings (NFDs) based on polyurethane (PU) and marine polysaccharides (i.e., hydroxypropyl trimethyl ammonium chloride chitosan, HACC and sodium alginate, SA) were accomplished by electrospinning and freeze-drying protocols. The 20(R)-ginsenoside Rg3 (Rg3) was further loaded into these NFDs to inhibit the formation of excessive wound scars. The PU/HACC/SA/Rg3 dressings showed a sandwich-like structure. The Rg3 was encapsulated in the middle layers of these NFDs and slowly released over 30 days. The PU/HACC/SA and PU/HACC/SA/Rg3 composite dressings demonstrated superior wound healing potentials over other NFDs. These dressings also displayed favorable cytocompatibility with keratinocytes and fibroblasts and could dramatically accelerate epidermal wound closure rate following 21 days of the treatment of a deep burn wound animal model. Interestingly, the PU/HACC/SA/Rg3 obviously reduced the excessive scar formation, with a collagen type I/III ratio closer to the normal skin. Overall, this study represented PU/HACC/SA/Rg3 as a promising multifunctional wound dressing, which promoted the regeneration of burn skins and attenuated scar formation.

Bifunctional Role of Monocyte Subsets in Modulating Radiotherapy Combined Intra-Tumor αCD40 Agonist Induced Abscopal Effect

PURPOSE/OBJECTIVE(S)

Abscopal effect induced by radiotherapy and immune checkpoint blockade is a promising yet far from satisfactory strategy in clinical. The underlying immune mechanism, especially driven by monocytes remains poorly undefined. Monocytes consist of two phenotypically and functionally distinct subsets distinguished by expression of chemokine receptors CCR2 and CX3CR1: classical inflammatory Ly6ChiCCR2hi monocytes and nonclassical patrolling Ly6CloCCR2loCX3CR1hi monocytes. Monocytes differentiate and transit to other myeloid cells such as dendritic cells and macrophages according to various environmental cues. Herein we investigated the roles of monocyte subsets in modulating tumor control consisting of combination RT and myeloid checkpoint agonist αCD40 to specifically ignite myeloid cell activation.

MATERIALS/METHODS

To establish abscopal model, contralateral tumors were implanted in each mouse, while only one side were treated with RT (8 Gy × 3) + αCD40 agonist (50 μg, intra-tumor). Tumor volume and mice survival were compared in each group (control, RT, αCD40 and RT + αCD40). Ccr2RFP/+ Cx3cr1GFP/+ (R2 × 3), Ccr2RFP/RFPCx3cr1+/+ (R2-KO) and Ccr2+/+Cx3cr1GFP/GFP (X3-KO) mice were used for cell tracking and to dissect chemokine receptor CCR2 and CX3CR1 on monocyte. Tumor infiltrating immune cells were analyzed by flowcytometry and RNA-seq.

RESULTS

RT combined with αCD40 significantly dampened tumor growth on both ipsilateral and contralateral sides in abscopal model (p< 0.01), accompanied by upregulation of chemokine receptors CCR2 and CX3CR1 on myeloid cells were both increased in tumor and peripheral blood. Chemokine ligands CCL2, CCL3, CCL5, CCL7, CCL12 and CX3CL1 were upregulated in tumor after RT and αCD40 treatment, recruiting CCR2 and CX3CR1 expressing monocytes in situ. To elucidate the roles of CCR2 and CX3CR1 in mediating local and systemic anti-tumor immunity, R2 × 3, R2-KO and X3-KO mice with combined treatment were used. Tumor size on ipsilateral leg were similar among groups. However, tumor growth was significantly delayed on contralateral side in X3-KO mice while accelerated in R2-KO mice compared with that in R2 × 3 mice. Mechanistically, remarkable decrease of antigen presenting dendritic cells (MHCII+Ly6ChiCD11c+) were observed in R2-KO mice. Moreover, phagocytosis was strengthened in macrophages (F4/80+CD11b+) of X3-KO mice.

CONCLUSION

CX3CR1 deletion ignite anti-tumor immunity elicited by RT and αCD40 through enhanced phagocytosis in macrophages, while CCR2 deletion renders inferior tumor control through reduction of dendritic cells. Preferential targeting nonclassical patrolling monocyte may lead to enhanced local and systemic tumor control.