A single cell atlas of frozen shoulder capsule identifies features associated with inflammatory fibrosis resolution.

Frozen shoulder is a spontaneously self-resolving chronic inflammatory fibrotic human disease, which distinguishes the condition from most fibrotic diseases that are progressive and irreversible. Using single-cell analysis, we identify pro-inflammatory MERTKlowCD48+ macrophages and MERTK + LYVE1 + MRC1+ macrophages enriched for negative regulators of inflammation which co-exist in frozen shoulder capsule tissues. Micro-cultures of patient-derived cells identify integrin-mediated cell-matrix interactions between MERTK+ macrophages and pro-resolving DKK3+ and POSTN+ fibroblasts, suggesting that matrix remodelling plays a role in frozen shoulder resolution. Cross-tissue analysis reveals a shared gene expression cassette between shoulder capsule MERTK+ macrophages and a respective population enriched in synovial tissues of rheumatoid arthritis patients in disease remission, supporting the concept that MERTK+ macrophages mediate resolution of inflammation and fibrosis. Single-cell transcriptomic profiling and spatial analysis of human foetal shoulder tissues identify MERTK + LYVE1 + MRC1+ macrophages and DKK3+ and POSTN+ fibroblast populations analogous to those in frozen shoulder, suggesting that the template to resolve fibrosis is established during shoulder development. Crosstalk between MerTK+ macrophages and pro-resolving DKK3+ and POSTN+ fibroblasts could facilitate resolution of frozen shoulder, providing a basis for potential therapeutic resolution of persistent fibrotic diseases.

Three-dimensional, in-vitro approaches for modelling soft-tissue joint diseases.

Diseases affecting the soft tissues of the joint represent a considerable global health burden, causing pain and disability and increasing the likelihood of developing metabolic comorbidities. Current approaches to investigating the cellular basis of joint diseases, including osteoarthritis, rheumatoid arthritis, tendinopathy, and arthrofibrosis, involve well phenotyped human tissues, animal disease models, and in-vitro tissue culture models. Inherent challenges in preclinical drug discovery have driven the development of state-of-the-art, in-vitro human tissue models to rapidly advance therapeutic target discovery. The clinical potential of such models has been substantiated through successful recapitulation of the pathobiology of cancers, generating accurate predictions of patient responses to therapeutics and providing a basis for equivalent musculoskeletal models. In this Review, we discuss the requirement to develop physiologically relevant three-dimensional (3D) culture systems that could advance understanding of the cellular and molecular basis of diseases that affect the soft tissues of the joint. We discuss the practicalities and challenges associated with modelling the complex extracellular matrix of joint tissues-including cartilage, synovium, tendon, and ligament-highlighting the importance of considering the joint as a whole organ to encompass crosstalk across tissues and between diverse cell types. The design of bespoke in-vitro models for soft-tissue joint diseases has the potential to inform functional studies of the cellular and molecular mechanisms underlying disease onset, progression, and resolution. Use of these models could inform precision therapeutic targeting and advance the field towards personalised medicine for patients with common musculoskeletal diseases.

A rapid high throughput bioprinted colorectal cancer spheroid platform forin vitrodrug- and radiation-response.

We describe the development of a high-throughput bioprinted colorectal cancer (CRC) spheroid platform with high levels of automation, information content, and low cell number requirement. This is achieved via the formulation of a hydrogel bioink with a compressive Young's modulus that is commensurate with that of colonic tissue (1-3 kPa), which supports exponential growth of spheroids from a wide range of CRC cell lines. The resulting spheroids display tight cell-cell junctions, bioink matrix-cell interactions and necrotic hypoxic cores. By combining high content light microscopy imaging and processing with rapid multiwell plate bioprinting, dose-response profiles are generated from CRC spheroids challenged with oxaliplatin (OX) and fluorouracil (5FU), as well as radiotherapy. Bioprinted CRC spheroids are shown to exhibit high levels of chemoresistance relative to cell monolayers, and OX was found to be significantly less effective against tumour spheroids than in monolayer culture, when compared to 5FU.

Heart Rate Assessment during Neonatal Resuscitation.

Approximately 10% of newborn infants require some form of respiratory support to successfully complete the fetal-to-neonatal transition. Heart rate (HR) determination is essential at birth to assess a newborn's wellbeing. Not only is it the most sensitive indicator to guide interventions during neonatal resuscitation, it is also valuable for assessing the infant's clinical status. As such, HR assessment is a key step at birth and throughout resuscitation, according to recommendations by the Neonatal Resuscitation Program algorithm. It is essential that HR is accurate, reliable, and fast to ensure interventions are delivered without delay and not prolonged. Ineffective HR assessment significantly increases the risk of hypoxic injury and infant mortality. The aims of this review are to summarize current practice, recommended techniques, novel technologies, and considerations for HR assessment during neonatal resuscitation at birth.

Doppler Ultrasound for Heart Rate Assessment in a Porcine Model of Neonatal Asphyxia.

Objectives: Approximately 10% of newborn infants require resuscitation at birth. Accurate heart rate (HR) assessment guides resuscitation interventions, thereby reducing morbidities and mortality. While existing HR assessment methods have several limitations, the Doppler ultrasound (Doppler-US) might be a promising alternative. We aimed to evaluate accuracy and optimal use of Doppler-US for HR assessments during neonatal asphyxia in a pre-clinical model. Design: HR assessments were performed in 16 term newborn piglets that were anesthetized, intubated, and instrumented. Study I evaluated optimal transducer position, Study II compared aortic (AV) and pulmonary (PV) examination modes, and Study III examined accuracy during asphyxia, for HR assessment. Setting: Experimental setting. Subjects: Asphyxia-induced piglets. Interventions: Study I: Doppler-US (USCOM® 1A) HR was assessed on upper (A), middle (B), and lower (C) third of the sternum; study II: Doppler-US HR was assessed using AV and PV examination modes; study III: HR was assessed during asphyxia. Comparisons were made between Doppler-US and the clinical gold standard for HR assessments, electrocardiography (ECG). Measurements and Main Results: Study I: Mean (SD) Doppler-US HR at position A, B, and C showed no difference when compared to ECG HR. Study II: The mean (SD) Doppler-US HR using AV and PV modes also showed no difference when compared to ECG HR. Study III: Bland-Altman analysis revealed a mean difference (95% limits of agreement) between Doppler-US and ECG HR of 1.5 (-16 to 19) bpm. Additionally, motion artifacts produced false peaks and peak size was seen to decrease as bradycardia progressed. Conclusions: HR assessment using Doppler-US during asphyxia is accurate but has limitations and must be further evaluated prior to clinical use. Doppler-US can be positioned along the sternum and use either AV or PV mode for accurate assessments in a piglet model of neonatal asphyxia.

Evaluation of a Tap-Based Smartphone App for Heart Rate Assessment During Asphyxia in a Porcine Model of Neonatal Resuscitation.

Objectives: Heart rate (HR) is the most significant parameter to assess a newborn's clinical status at birth. Recently, novel technologies including smartphone applications have been suggested for HR assessment during neonatal resuscitation. The aim of this study was to evaluate the accuracy, speed, and precision of the NeoTapLifeSupport (NeoTapLS) smartphone application using a digital stethoscope (DS) for HR assessment during neonatal resuscitation. Design: Newborn piglets (n = 20, 1-3 days, 1.7-2.4 kg) were anesthetized, intubated, mechanically ventilated, and subjected to 30 min of hypoxia, followed by asphyxia. Asphyxia was induced by clamping the endotracheal tube and disconnecting the ventilator, until asystole was confirmed by zero carotid blood flow (CBF). Setting: Experimental setting. Subjects: Asphyxia-induced newborn piglets. Interventions: During asphyxia, HR assessments were performed with a DS using the NeoTapLS smartphone application, and compared to 6-s method (6 s), and 10-s method (10 s). Measurements and Main Results: Accuracy of obtained HRs was compared to CBF and electrocardiogram and assessment time using NeoTapLS, 6 s, and 10 s were also measured. The mean(SD) HR with the NeoTapLS was 68(26), compared to CBF with 68(27) bpm, 6 s with 68(27), and 10 s with 66(26) bpm during asphyxia. Bland-Altman analysis revealed no difference between HR using the NeoTapLS, 6 s, 10 s, compared to CBF HR, with NeoTapLS showing the smallest difference between 95% limits of agreement. The median (IQR) time required to obtain a HR using the NeoTapLS was 3(2-4) s, compared to 6(6-7), and 10(10-11) s for 6 and 10 s, respectively. Conclusions: Our data suggests that the NeoTapLS is accurate, fast, and precise during neonatal asphyxia to assess heart rate.

Novel technologies for heart rate assessment during neonatal resuscitation at birth - A systematic review.

BACKGROUND: 6.5-9 million newborns worldwide require resuscitation at birth annually. During neonatal resuscitation, inaccurate or slow heart rate (HR) assessments may significantly increase risk of infant mortality or morbidity. Therefore fast, accurate, and effective HR assessment tools are critical for neonatal resuscitation. OBJECTIVE: To systematically review the literature about accuracy, latency, and efficacy of technologies for HR assessment during neonatal resuscitation. METHODS: Adhering to PRISMA guidelines, PubMed, EMBASE, and Google Scholar databases were systematically searched to identify studies related to technologies for HR assessment, which could be used to guide neonatal resuscitation. RESULTS: Forty-six studies evaluating HR assessment technologies for neonatal resuscitation were identified. In total, 16 studies (3/16 randomized trials and 13/16 observational studies) compared two or more HR assessment technologies to measure accuracy, latency, and efficacy. Of the trials, 1/3 had a low risk of bias while 2/3 had high risks. All observational studies had high risks of bias. Most studies considered infants not requiring resuscitation, constituting indirect evidence and lower certainty in the context of neonatal resuscitation. Two trials reported faster times to HR assessment using electrocardiogram with a mean(SD) 66(20) versus 114(39) s and a median(IQR) 24(19-39) versus 48(36-69) s (both p < 0.001), compared to pulse oximetry. CONCLUSION: While electrocardiography is faster to assess HR at birth and more reliable to detect HR changes compared to other recommended technologies, practice should not exclusively rely on ECG. While novel technologies could support HR assessment, no studies validate their clinical efficacy during neonatal resuscitation.