Tissue Collapse Research Articles

Unravelling the effects of drying techniques on Porphyra yezoensis: Morphology, rehydration properties, metabolomic profile, and taste formation

This study explored the impact of sun drying (SD), freeze drying (FD), oven drying (OD), and microwave drying (MD) on the morphology, rehydration properties, metabolomic profile, and taste formation of Porphyra yezoensis. FD elicited a brighter colour, smooth surface, porous microstructure, and strong rehydration properties in P. yezoensis, while dramatically maintaining the umami, sweetness, and saltiness. OD and MD decreased structural openness owing to tissue collapse and affected water absorption. Metabolomic analysis revealed 1030 metabolites, among which taste-related compounds, especially free amino acids, nucleotides, organic acids, and their derivatives, were the main biomarkers for distinguishing the different drying methods. Their related metabolic pathways, such as taurine and hypotaurine metabolism; purine metabolism; glyoxylate and dicarboxylate metabolism; and citrate cycle, were the most active. A metabolic pathway network of the main taste compounds was built to provide novel insights into the mechanisms underlying the taste profile changes associated with different drying methods.

The Papilla Base CTG: A Novel Approach for Interdental Soft Tissue Reconstruction.

Impairment or loss of interdental papilla is a common issue in patients with periodontal disease, leading to phonetic, functional, and aesthetic concerns. Numerous techniques have been explored to reconstruct and regenerate interdental papillae, but consistent success remains challenging. This article presents a novel surgical approach that applies the principles of the Connective Tissue Graft (CTG) wall technique to enhance papilla volume when interdental clinical attachment loss is present in the aesthetic zone. The case of a 35-year-old woman with an RT3 recession defect associated with loss of interdental hard and soft tissues is discussed. The patient underwent a procedure involving palatal incisions, application of amelogenins, and a trapezoidal shape CTG fixed at the base of the papilla under a coronally advanced flap. This approach aimed to stabilize the blood clot and prevent soft tissue collapse into the defect area, enhancing the position and volume of the interdental papilla. Results at 6- and 12-months follow-up indicated significant improvement in papilla appearance and complete root coverage. This case suggests that the modified CTG wall technique can effectively treat buccal and interdental gingival recessions associated with horizontal or infrabony defects. Further clinical trials are necessary to confirm these findings and establish the most effective approach for interdental papilla reconstruction.

Oscillatory airflow through the hypopharyngeal and supraglottic airway

Exercise-induced laryngeal obstruction (EILO) is a known cause of exertional dyspnoea, characterised by paradoxical inward collapse of laryngeal tissues. The pathophysiological mechanisms of EILO remain to be fully established, but insufficient mechanical resistance of laryngeal tissues to air-induced loads is hypothesised. It is understood that airflow and anatomic configurations of the airway play a key role in the wall pressure distribution of the larynx. While breathing is a cyclic process with directional changes of airflow, the literature is confined to steady, unidirectional airflow. It is necessary to assess the role of oscillatory airflow on the loads on the laryngeal airway. This study investigates the effect of oscillatory airflow on the laryngeal flow fields and air-induced loads. A computational fluid dynamics model of the upper respiratory tract (URT) is developed using the Reynolds-averaged Navier-Stokes equations. Five oscillatory airflow cases through a single geometry are considered, utilising sinusoidal breathing cycles with different breathing frequencies (24, 32 and 40 breaths per minute) and peak inspiratory flow rates (96, 168 and 240 L/min). Results include the airflow velocity distribution in the URT, and the air-induced pressure and forces. It is demonstrated that inspiratory velocity distribution varies with breathing frequency and intensity. The force acting on the URT walls are in-phase with the airflow rate and therefore exhibit quasi-steady behaviour. These findings are also reflected in the force vectors acting on the aryepiglottic folds and indicate that air-induced closure of the supraglottis in EILO is influenced by the breathing intensity rather than the breathing frequency.

Optimal Timing of Cranioplasty After Decompressive Craniectomy: Timing or Collapse Ratio.

Although cranioplasty (CP) is a relatively straightforward surgical procedure, it is associated with a high complication rate. The optimal timing for this surgery remains undetermined. This study aimed to identify the most suitable timing for CP to minimize postoperative complications. We conducted a retrospective analysis of all CP cases performed in our department from August 2015 to March 2022. Data were gathered through case statistics and categorized based on the occurrence of complications. The collapse ratio was determined using 3-dimensional Slicer software. In our retrospective study of 266 patients, 51 experienced postoperative complications, including hydrocephalus, epidural effusion, subdural hematoma, epilepsy, and subcutaneous infection. Logistic regression analysis identified independent predictors of postcranioplasty complications, and a nomogram was developed. The predictive value of the logistic regression model, collapse ratio, and decompression craniotomy-CP operation interval for post-skull repair complications was assessed using receiver operating characteristic curve analysis. No significant differences were observed in postoperative complications and decompression craniotomy-CP intervals between the groups (P = .07, P > .05). However, significant differences were noted in postoperative collapse ratios and CP complications between the groups (P = .023, P < .05). Logistic regression revealed that the collapse ratio (odds ratio = 1.486; 95% CI: 1.001-2.008; P = .01) and CP operation time (odds ratio = 1.017; 95% CI: 1.008-1.025, P < .001) were independent risk factors for postoperative complications. Receiver operating characteristic curve analysis indicated that the collapse ratio could predict CP postoperative complications, with a cutoff value of 0.274, an area under the curve of 0.621, a sensitivity of 62.75%, and a specificity of 63.26%. The post-skull repair collapse ratio is a significant predictor of postoperative complications. It is advisable to base the timing of surgery on the extent of brain tissue collapse, rather than solely on the duration between cranial decompression and CP.

Pediatric Atelectasis: Insights from Diagnostic Imaging

This article presents a detailed case study of a 10-year-old child, born in 2013, exhibiting symptoms of a febrile syndrome and subsequent diagnostic findings suggestive of atelectasis through chest radiography and Computed Tomography (CT) scans without intravenous contrast. Atelectasis, a condition characterized by the collapse of lung tissue, represents a significant diagnostic challenge in pediatric patients. This study delves into the radiographic and CT findings, emphasizing the importance of imaging in diagnosing and managing atelectasis.

Soft Tissue Response and Determination of Underlying Risk Drivers for Recession and Mucositis after AMSJI Implantation in the Maxilla.

To evaluate the soft tissue response to the placement of additively manufactured subperiosteal jaw implants (AMSJI) in the severely atrophic maxilla and to identify possible risk factors for soft tissue breakdown. An international multicenter study was conducted, and 15 men (mean age: 64.62 years; SD: ± 6.75) and 25 women (mean age: 65.24 years; SD: ± 6.77) with advanced maxillary jaw resorption (Cawood and Howell Class V or more) were included in this study. General patient data were collected, and all subjects were clinically examined. Inclusion criteria were patients who underwent bilateral AMSJI placement in the maxilla at least 1 year prior. Exclusion criteria were patients who did not have patient, surgeon, or dentist consent to participate in the study before their inclusion. A total of 40 patients were enrolled, with a mean follow-up period of 917 days (SD: ± 306.89 days). Primary implant stability was achieved postoperatively in all cases, and all implants were loaded with a final prosthesis. At the time of the study, only 1 patient showed mobility (> 1 mm) of the bilateral AMSJI. Due to mucosal recession, exposure of the framework was seen in 26 patients (65%) and was mainly in the left (21.43% of 26) and right (18.57% of 26) midlateral region. A thin biotype and the presence of mucositis were found to be risk factors (P < .05). Although not significant, smokers had a risk of developing a recession that was nearly seven times (odds ratio: 6.88; P = .08) greater than that of nonsmokers. Twenty-six (65%) patients presented with a recession in one (or more) of the seven regions after oral rehabilitation with bilateral AMSJI placement. Several risk drivers were evaluated. The collapse of soft tissues around the AMSJI that led to caudal exposure of the arms was correlated with a thin biotype and the presence of mucositis.

Two transcription factors, RhERF005 and RhCCCH12, regulate rose resistance to Botrytis cinerea by modulating cytokinin levels.

Gray mold caused by the necrotrophic fungal pathogen Botrytis cinerea is one of the most destructive diseases in rose (Rosa spp.). Rose infection by B. cinerea leads to severe economic losses due to necrosis, tissue collapse, and rot. In rose, cytokinins (CKs) positively regulate a defense response to B. cinerea, but little is known about the underlying molecular mechanisms. Here, we characterized two ethylene/jasmonic acid-regulated transcription factors, RhEFR005 and RhCCCH12, that bind to the promoter region of PATHOGENESIS-RELATED 10.1 (RhPR10.1) and promote its transcription, leading to decreased susceptibility to B. cinerea. The RhEFR005/RhCCCH12-RhPR10.1 module regulated cytokinin content in rose, and the susceptibility of RhEFR005-, RhCCCH12-, and RhPR10.1-silenced rose petals can be rescued by exogenous CK. In summary, our results reveal that the RhERF005/RhCCCH12-RhPR10.1 module regulates the CK-induced defense response of rose to B. cinerea.

The use of protective mechanical ventilation during extracorporeal membrane oxygenation for the treatment of acute respiratory failure.

Acute respiratory failure (ARF) strikes an estimated two million people in the United States each year, with care exceeding US$50 billion. The hallmark of ARF is a heterogeneous injury, with normal tissue intermingled with a large volume of low compliance and collapsed tissue. Mechanical ventilation is necessary to oxygenate and ventilate patients with ARF, but if set inappropriately, it can cause an unintended ventilator-induced lung injury (VILI). The mechanism of VILI is believed to be overdistension of the remaining normal tissue known as the 'baby' lung, causing volutrauma, repetitive collapse and reopening of lung tissue with each breath, causing atelectrauma, and inflammation secondary to this mechanical damage, causing biotrauma. To avoid VILI, extracorporeal membrane oxygenation (ECMO) can temporally replace the pulmonary function of gas exchange without requiring high tidal volumes (VT) or airway pressures. In theory, the lower VT and airway pressure will minimize all three VILI mechanisms, allowing the lung to 'rest' and heal in the collapsed state. The optimal method of mechanical ventilation for the patient on ECMO is unknown. The ARDSNetwork Acute Respiratory Management Approach (ARMA) is a Rest Lung Approach (RLA) that attempts to reduce the excessive stress and strain on the remaining normal lung tissue and buys time for the lung to heal in the collapsed state. Theoretically, excessive tissue stress and strain can also be avoided if the lung is fully open, as long as the alveolar re-collapse is prevented during expiration, an approach known as the Open Lung Approach (OLA). A third lung-protective strategy is the Stabilize Lung Approach (SLA), in which the lung is initially stabilized and gradually reopened over time. This review will analyze the physiologic efficacy and pathophysiologic potential of the above lung-protective approaches.

NAC61 regulates late- and post-ripening osmotic, oxidative, and biotic stress responses in grapevine.

During late- and post-ripening stages, grape berry undergoes profound biochemical and physiological changes whose molecular control is poorly understood. Here, we report the role of NAC61, a grapevine NAC transcription factor, in regulating different processes involved in berry ripening progression. NAC61 is highly expressed during post-harvest berry dehydration and its expression pattern is closely related to sugar concentration. The ectopic expression of NAC61 in Nicotiana benthamiana leaves resulted in low stomatal conductance, high leaf temperature, tissue collapse and a higher relative water content. Transcriptome analysis of grapevine leaves transiently overexpressing NAC61 and DNA affinity purification and sequencing analyses allowed us to narrow down a list of NAC61-regulated genes. Direct regulation of the stilbene synthase regulator MYB14, the osmotic stress-related gene DHN1b, the Botrytis cinerea susceptibility gene WRKY52, and NAC61 itself was validated. We also demonstrate that NAC61 interacts with NAC60, a proposed master regulator of grapevine organ maturation, in the activation of MYB14 and NAC61 expression. Overall, our findings establish NAC61 as a key player in a regulatory network that governs stilbenoid metabolism and osmotic, oxidative, and biotic stress responses that are the hallmark of late- and post-ripening grape stages.

HIDROPNEUMOTHORAKS ET CAUSA TB PARU

Hydropneumothorax is a condition where there is air and fluid in the pleural cavity resulting in the collapse of lung tissue. The exact incidence is unknown but it is found that the incidence of pneumothorax ranges from 2.4 to 17.8/100,000 population per year. In this case, a 42-year-old man with complaints of chest pain since 2 weeks before admission to the hospital. The complaints included shortness of breath and continuous coughing. From the examination results obtained BP 120/80, HR: 135x/I, RR: 18 x/I, and temperature: 37oC. Physical examination found asymmetrical chest movements, chest tube in the sinistra thorax, weak vocal fremitus in the basal part of the left hemithorax at the level of posterior ICS XI, hypersonor in the right lung at the level of ICS II-IV and dimmed in the left basal part at the level of ICS V and a decrease in left lung breath sounds. X-ray examination showed an area of lusensi without pulmonary scars in the lateral aspect of the sinistral hemithorax with a ridge in the basal aspect of the sinistral hemithorax accompanied by an air fluid level in the left hemithorax. The patient was diagnosed with hydropneumothorax ec pulmonary tuberculosis with water seal drainage.

Dental Implant Treatment Planning in the Post-Traumatic Rehabilitation of the Anterior Maxilla: A Report of Three Cases

Evidence-based algorithms guiding treatment of traumatic dentoalveolar injuries prescribe specific interventions in the presence of various sets of historical and clinical cues. However, the staging of dental implant placement in post-traumatic rehabilitation—indeed, whether to consider implant therapy at all—remains more art than science, prior authors cautioning that universal rules do not apply. The purpose of this report is to present treatment approaches applied in three traumatic episodes involving the anterior maxilla. Three patients presented to the Department of Periodontics, Army Postgraduate Dental School, Postgraduate Dental College, Fort Eisenhower, GA, USA, following traumatic injuries to the anterior maxilla with varying degrees of severity. In two cases, central incisors were replaced using immediate implants and immediate provisionalization (IIPP). At one IIPP site, extraction was delayed for eight weeks to permit healing of an alveolar fracture. In the third case, the patient received a non-implant rehabilitation due to severe alveolar destruction. Both patients receiving IIPP expressed satisfaction with immediate esthetics, and in both cases, the provisional restoration prevented extraction-related soft tissue collapse. Trauma adds an element of uncertainty to the technically demanding task of implant placement in the esthetic zone. When appropriate, IIPP in the post-traumatic rehabilitation of the anterior maxilla may mitigate some of the known biopsychosocial consequences of oral trauma and facilitate development of favorable mucosal and osseous architecture at the site. Individualized treatment planning is critically important due to wide variability in site characteristics and injury complexity.

Electrohydrodynamic drying of citrus (Citrus sinensis L.) peel: Comparative evaluation on the physiochemical quality and volatile profiles.

Based on the concept of circular economy, citrus peel was considered a valuable source of bioactive compounds for high-value foods. Electrohydrodynamic (EHD) drying is a novel technology appropriated for the dehydration of heat-sensitive products such as citrus peel. In current work, EHD drying of citrus peel was performed based on alternating current (AC) or direct current (DC) sources at various voltage levels (9, 18, 27, 36, and 45kV). The effect of EHD on drying characteristics, water retention capacity, enzyme inactivation, phytochemical contents (phenolic compounds and carotenoids), and volatile compounds of citrus peel were evaluated and compared. Results showed that the drying time in the AC electric field was shorter compared to DC electric field at the same applied voltages due to the polarization layer formed by unipolar charges. The applied voltage determined electric field strength as well as the degree of tissue collapse and cell membrane rupture. EHD elucidated the transformation and degradation of phytochemicals including phenolic compounds, carotenoids, and volatile composition in proportion to the applied voltage. The findings indicate that EHD drying with AC improves drying behaviors, inactivates enzymes, and retains the phytochemical properties of citrus peel.

Integrating Melt Electrowriting and Fused Deposition Modeling to Fabricate Hybrid Scaffolds Supportive of Accelerated Bone Regeneration.

Emerging additive manufacturing (AM) strategies can enable the engineering of hierarchal scaffold structures for guiding tissue regeneration. Here, the advantages of two AM approaches, melt electrowriting (MEW) and fused deposition modelling (FDM), are leveraged and integrated to fabricate hybrid scaffolds for large bone defect healing. MEW is used to fabricate a microfibrous core to guide bone healing, while FDM is used to fabricate a stiff outer shell for mechanical support, with constructs being coated with pro-osteogenic calcium phosphate (CaP) nano-needles. Compared to MEW scaffolds alone, hybrid scaffolds prevent soft tissue collapse into the defect region and support increased vascularization and higher levels of new bone formation 12 weeks post-implantation. In an additional group, hybrid scaffolds are also functionalized with BMP2 via binding to the CaP coating, which further accelerates healing and facilitates the complete bridging of defects after 12 weeks. Histological analyses demonstrate that such scaffolds support the formation of well-defined annular bone, with an open medullary cavity, smooth periosteal surface, and no evidence of abnormal ectopic bone formation. These results demonstrate the potential of integrating different AM approaches for the development of regenerative biomaterials, and in particular, demonstrate the enhanced bone healing outcomes possible with hybrid MEW-FDM constructs.

Preventive effect of lactoferrin peptides on ulcerative colitis

Lactoferrin (LF) plays an essential immunomodulatory role, yet its underlying mechanisms remain unclear. Here, we investigated the suppressive effects of bovine LF and its peptide derivatives (at positions 17–28 of the primary structure) on ulcerative colitis (UC) using a dextran sodium sulphate (DSS)-induced UC mouse model. LF peptides and their amide bodies alleviated DSS-induced colon atrophy. Mice orally administered with LF and its peptides showed decreased epithelial tissue collapse and preserved crypt structure. Additionally, measurement of lipopolysaccharide (LPS) -induced inflammatory cytokine levels in cell culture systems, using macrophage-like RAW264.7, neutrophil-like HL-60, and intestinal epithelium-like Caco-2 cells, suggested the anti-inflammatory effect of LF peptides on intestinal immune function as a possible mechanism underlying LF-induced suppression of UC onset. Thus, LF peptide derivatives may be useful for treating some inflammatory diseases, as the modulatory effect of LF peptide and its amide body was more effective than that of LF.

Influence of wood type on anthraquinone levels and quality properties of smoked chipotle pepper

This study aimed to assess the effects of pecan and mesquite wood, as well as smoking time, on anthraquinone (AQ) levels and quality properties of chipotle pepper (CHP) during the traditional smoking process. Changes in moisture content, microstructure, levels of total phenols (TPs), AQ, capsaicin (CAPS), dihydrocapsaicin (DHC), total polyphenols (TPPs), and total antioxidant activity (TAA), as well as color parameters, were measured. A wood mixture consisting of pecan, poplar, mesquite, and pine was used as the control. The CHP moisture content consistently decreased from 12 to 108 h of smoking, with long times exhibiting asymptotic trends across all treatments. Concurrently, structural changes, such as pericarp thinning and plant tissue collapse, were observed as the smoking process progressed. The wood type and processing time had a significant impact (P < 0.05) on TPs, AQ, CAPS, DHC, TAA levels, and color. TPs and AQ exhibited behavior opposite to that of the moisture content. CHP smoked in mesquite wood exhibited the highest TPs absorption rate and the lowest AQ levels. However, the AQ levels in CHP using any wood type exceeded permissible limits (0.02 mg·kg−1) at 12 h of processing, with the control exhibiting the highest AQ concentrations. The highest concentrations of CAPS and DHC were observed at 36 h in all treatments, with lower losses in mesquite wood CHP. The control exhibited the highest TAA values compared to fresh peppers. CHP color (a*, redness) decreased throughout the smoking process. The pecan and mesquite wood treatments resulted in the lowest loss of a* (P < 0.05). These results indicate that using mesquite wood for CHP production promotes higher TPs concentrations with lower AQ levels, followed by pecan wood, when compared to the control. These findings suggest the need to investigate the mechanisms of AQ formation to achieve CHP parameters within the regulatory limits with good quality.

Acquired laryngomalacia as a cause of post-extubation stridor and extubation failure following craniotomy: a case report

BackgroundLaryngomalacia is a dynamic airway condition characterized by flaccid laryngeal tissue and inward collapse of supraglottic structures during inspiration. Although it may cause airway obstruction and requires careful management, there have been few reports regarding laryngomalacia after surgery. We report a case of adult-onset laryngomalacia occurred after craniotomy requiring reintubation.Case presentationA 21-year-old man was admitted to the ICU after craniotomy for a cerebellopontine angle tumor. He developed severe stridor immediately after extubation on the postoperative day 2 and required reintubation. On the postoperative day 5, similar episode occurred following re-extubation and fiberoptic laryngoscopy revealed a collapsed epiglottis and left arytenoid into the glottis. A diagnosis of laryngomalacia was made, and he underwent tracheostomy. Laryngomalacia had completely improved; however, bilateral vocal cord paralysis was detected 2 weeks later.ConclusionsAcquired laryngomalacia should be considered as a possible mechanism of the airway symptoms in a patient with neurological dysfunction.

Neuroprotective effects of interleukin 10 in spinal cord injury.

Spinal cord injury (SCI) starts with a mechanical and/or bio-chemical insult, followed by a secondary phase, leading progressively to severe collapse of the nerve tissue. Compared to the peripheral nervous system, injured spinal cord is characterized by weak axonal regeneration, which leaves most patients impaired or paralyzed throughout lifetime. Therefore, confining, alleviating, or reducing the expansion of secondary injuries and promoting functional connections between rostral and caudal regions of lesion are the main goals of SCI therapy. Interleukin 10 (IL-10), as a pivotal anti-inflammatory and immunomodulatory cytokine, exerts a wide spectrum of positive effects in the treatment of SCI. The mechanisms underlying therapeutic effects mainly include anti-oxidative stress, limiting excessive inflammation, anti-apoptosis, antinociceptive effects, etc. Furthermore, IL-10 displays synergistic effects when combined with cell transplantation or neurotrophic factor, enhancing treatment outcomes. This review lists pleiotropic mechanisms underlying IL-10-mediated neuroprotection after SCI, which may offer fresh perspectives for clinical translation.

"Usefulness of the Acute Phase Reactants (APR) score (Part 2): Characteristics of the APR-Score in Wilson-Mikity Syndrome"

The etiology of Wilson-Mikity syndrome (WMS) remains uncertain. Inflammation of the fetal lung caused by intrauterine infection spilling over into the lungs results in lung tissue collapse and birth before complete repair is achieved. Continued spontaneous breathing exacerbates lung damage that results in the development of chronic lung disease.

1-MCP prevents ultrastructural changes in the organelles of Dendrobium petals that are induced by exogenous ethylene

Ethylene is a plant hormone that causes flower senescence. Dendrobium flowers are sensitive to ethylene and ethylene can induce premature senescence depending on the cultivar and the ethylene concentration. Dendrobium ‘Lucky Duan’ is one of the most sensitive cultivars to ethylene exposure. Open florets of ‘Lucky Duan’ were subjected to ethylene, 1-MCP, or 1-MCP plus ethylene treatments and compared with an untreated control. Ethylene induced earlier development of color fading, drooping and venation in petals, whereas 1-MCP pre-treatment counteracted these changes. Under light microscopy, epidermal cells and mesophyll parenchyma tissue around the vascular bundles of petals treated with ethylene showed collapsed cells whereas 1-MCP pre-treatment counteracted this collapse. An scanning electron microscopy (SEM) study confirmed clearly that ethylene treatment caused the collapse of mesophyll parenchyma tissue around vascular bundles. Ultrastructural changes were also studied using transmission electron microscopy (TEM) and showed that ethylene treatment induced morphological changes in conjunction with disorganization of the plasma membrane, the nuclei, chromatin, the nucleoli, myelin bodies, multivesicular bodies, and mitochondria including changes in size and number, breakages of membranes, enlargement of intercellular spaces and disintegration. 1-MCP pre-treatment was observed to counter these changes that were induced by ethylene. The role of ethylene-induced ultrastructural changes in the different organelles was apparently associated with membrane damage.

Investigating the contribution of hyaluronan to the breast tumour microenvironment using multiparametric MRI and MR elastography.

Hyaluronan (HA) is a key component of the dense extracellular matrix in breast cancer, and its accumulation is associated with poor prognosis and metastasis. Pegvorhyaluronidase alfa (PEGPH20) enzymatically degrades HA and can enhance drug delivery and treatment response in preclinical tumour models. Clinical development of stromal-targeted therapies would be accelerated by imaging biomarkers that inform on therapeutic efficacy in vivo. Here, PEGPH20 response was assessed by multiparametric magnetic resonance imaging (MRI) in three orthotopic breast tumour models. Treatment of 4T1/HAS3 tumours, the model with the highest HA accumulation, reduced T1 and T2 relaxation times and the apparent diffusion coefficient (ADC), and increased the magnetisation transfer ratio, consistent with lower tissue water content and collapse of the extracellular space. The transverse relaxation rate R2 * increased, consistent with greater erythrocyte accessibility following vascular decompression. Treatment of MDA-MB-231 LM2-4 tumours reduced ADC and dramatically increased tumour viscoelasticity measured by MR elastography. Correlation matrix analyses of data from all models identified ADC as having the strongest correlation with HA accumulation, suggesting that ADC is the most sensitive imaging biomarker of tumour response to PEGPH20.