Feasibility and outcomes of transjugular intrahepatic portosystemic shunts in infants.

BACKGROUND: Experience with transjugular intrahepatic portosystemic shunts (TIPS) in the pediatric population, especially in infants, is limited. OBJECTIVE: To evaluate the feasibility, efficacy and safety of TIPS placement in infants. MATERIALS AND METHODS: This retrospective non-comparative observational cohort study analyzed all pediatric patients < 12 months of age treated with TIPS while waiting for liver transplant between October 2018 and April 2021. The sample consisted of 10 infants with chronic liver disease. All had refractory ascites and decreased portal vein size. Their mean age ± standard deviation was 5 ± 1 months and their mean weight was 5.4 ± 1.0 kg. We calculated the pediatric end-stage liver disease score and portosystemic gradients before and after TIPS placement. We used ultrasound to check for complications and to assess the presence of ascites. We used paired-sample t-test for the mean comparison of paired variables. RESULTS: Ten TIPS procedures were performed that were technically and hemodynamically successful except for one, in which an extrahepatic portal puncture required surgical repair. Ascites resolved in three infants and was reduced in six. The portal vein size remained stable after TIPS placement. Four infants had early stent thrombosis and two had late stent thrombosis treated with angioplasty or covered stents. CONCLUSION: TIPS placement in infants is a feasible, safe and effective procedure.

Improved in vivo efficacy of clinical-grade cryopreserved human hepatocytes in mice with acute liver failure.

Clinical hepatocyte transplantation short-term efficacy has been demonstrated; however, some major limitations, mainly due to the shortage of organs, the lack of quality of isolated cells and the low cell engraftment after transplantation, should be solved for increasing its efficacy in clinical applications. Cellular stress during isolation causes an unpredictable loss of attachment ability of the cells, which can be aggravated by cryopreservation and thawing. In this work, we focused on the use of a Good Manufacturing Practice (GMP) solution compared with the standard cryopreservation medium, the University of Wisconsin medium, for the purpose of improving the functional quality of cells and their ability to engraft in vivo, with the idea of establishing a biobank of cryopreserved human hepatocytes available for their clinical use. We evaluated not only cell viability but also specific hepatic function indicators of the functional performance of the cells such as attachment efficiency, ureogenic capability, phase I and II enzymes activities and the expression of specific adhesion molecules in vitro. Additionally, we also assessed and compared the in vivo efficacy of human hepatocytes cryopreserved in different media in an animal model of acute liver failure. Human hepatocytes cryopreserved in the new GMP solution offered better in vitro and in vivo functionality compared with those cryopreserved in the standard medium. Overall, the results indicate that the new tested GMP solution maintains better hepatic functions and, most importantly, shows better results in vivo, which could imply an increase in long-term efficacy when used in patients.

Superior performance of 18F-fluorocholine digital PET/CT in the detection of parathyroid adenomas.

OBJECTIVE: To compare detectability of hyperfunctioning parathyroid tissue (HPT) by digital and analog 18F-fluorocholine PET/CT in patients with primary hyperparathyroidism and negative/inconclusive 99mTc-MIBI scintigraphy-SPECT/CT. MATERIALS AND METHODS: Thirty-three patients with primary hyperparathyroidism and negative/inconclusive 99mTc-MIBI scintigraphy-SPECT/CT were prospectively included. All patients accepted to be scanned by digital and analog PET/CT in the same imaging session after a single injection of 18F-fluorocholine. Three nuclear medicine physicians evaluated the digital and analog PET/CT datasets to assess the detection rate of HPT. Maximum standard uptake values (SUVmax) of HPT and locoregional lymph nodes were measured in both systems. RESULTS: HPT was detected in 30/33 patients by the digital system, whereas it was detected in 22/33 patients by the analog system (p < 0.01). Moreover, in 21 of these 33 patients, both systems detected one focal 18F-fluorocholine uptake, and in one patient the digital system detected two foci. Histopathology demonstrated HPT in 32 patients and it was inconclusive in one patient. The digital PET/CT detected HPT in 29 of the 32 patients, and the analog system in 22 of the 32 (p < 0.01). All HPT suspected lesions resected and detected only by the digital system (n = 8) were < 10 mm (7.5 ± 1.3 mm), while those detected by both systems (n = 22) were > 10 mm (13 ± 3.8 mm). SUVmax of HPT lesions was significantly higher than SUVmax of locoregional lymph node independently of the PET/CT system used (4.5 ± 1.9 vs. 2.9 ± 1.3, p < 0.0001). CONCLUSIONS: Digital PET/CT offers superior performance over analog system in patients with suspected HPT and previous negative/inconclusive imaging examinations, particularly in sub-centimeter lesions. SUVmax can help in the differentiation between HTP and locoregional lymph nodes.

Correction to: Superior performance of 18F-fluorocholine digital PET/CT in the detection of parathyroid adenomas.

The correct administered activity of 18F-FCH is 0.1-0.14 mCi/Kg, which is equivalent to 3.7-5.2 MBq/kg.

Correction to: Digital vs. analog PET/CT: intra-subject comparison of the SUVmax in target lesions and reference regions.

The article Digital vs. analog PET/CT: intra-subject comparison of the SUVmax in target lesions and reference regions, written by Francisco Fuentes-Ocampo, Diego Alfonso López-Mora, Albert Flotats, Gabriela Paillahueque.

Digital vs. analog PET/CT: intra-subject comparison of the SUVmax in target lesions and reference regions.

PURPOSE: The purpose of this study was to assess whether digital photon counting technology in digital PET/CT influences the quantification of SUVmax in target lesions and regions of reference compared to analog PET/CT before an interchangeable use of either system in follow up studies. METHODS: From January to June of 2018, 100 oncological patients underwent successive PET/CT imaging with digital and analog systems in the same day. Fifty-eight patients underwent analog imaging first and digital imaging thereafter, and 42 patients the other way round. SUVmax was measured in reference regions (liver and mediastinal blood pool) and in the most metabolically active target lesion in each patient. According to the sequence order of PET/CT acquisition, two groups of SUVmax values were obtained, i.e. group 1: analog PET/CT performed first; group 2: digital PET/CT performed first. RESULTS: Mean SUVmax in the total sample (regardless of the order of PET/CT acquisition) in the target lesions with the analog PET/CT was 8.14 ± 6.39 and the digital 9.97 ± 6.14 (P = 0.000). Total mean SUVmax in the liver with the analog was 4.39 ± 2.59 and the digital 4.46 ± 3.18 (P = 0.477). Total mean SUVmax in the mediastinal blood pool with the analog was 2.30 ± 0.67 and the digital 2.54 ± 0.74 (P = 0.000). Group 1: mean SUVmax in the target lesions with the analog system was 6.64 ± 4.71 and the digital 9.48 ± 5.60 (P = 0.000). Mean liver SUVmax with the analog was 4.70 ± 2.90 and the digital 4.80 ± 3.72 (P = 0.088). Mediastinal blood pool SUVmax with the analog was 2.33 ± 0.66 and the digital 2.45 ± 0.73 (P = 0.041). Group 2: mean SUVmax in target lesions with the digital system was 10.63 ± 6.88 and the analog 10.16 ± 7.76 (P = 0.046). Mean liver SUVmax with the digital was 3.99 ± 2.20 and the analog 3.96 ± 2.04 (P = 0.218). Mediastinal blood pool SUVmax with the digital was 2.66 ± 0.75 and the analog 2.27 ± 0.68 (P = 0.000). No significant differences between both time delays were found. CONCLUSIONS: Improved photon counting technology in the digital PET/CT, and the effect of delayed increased uptake and retention significantly increases SUVmax values. This has to be taken into account before interchangeable use of either system in follow up studies.

Comparison of image quality and lesion detection between digital and analog PET/CT.

OBJECTIVE: The purpose of this study was to compare image quality and lesion detection capability between a digital and an analog PET/CT system in oncological patients. MATERIALS AND METHODS: One hundred oncological patients (62 men, 38 women; mean age of 65 ± 12 years) were prospectively included from January-June 2018. All patients, who accepted to be scanned by two systems, consecutively underwent a single day, dual imaging protocol (digital and analog PET/CT). Three nuclear medicine physicians evaluated image quality using a 4-point scale (-1, poor; 0, fair; 1, good; 2, excellent) and detection capability by counting the number of lesions with increased radiotracer uptake. Differences were considered significant for a p value <0.05. RESULTS: Improved image quality in the digital over the analog system was observed in 54% of the patients (p = 0.05, 95% CI, 44.2-63.5). The percentage of interrater concordance in lesion detection capability between the digital and analog systems was 97%, with an interrater measure agreement of κ = 0.901 (p < 0.0001). Although there was no significant difference in the total number of lesions detected by the two systems (digital: 5.03 ± 10.6 vs. analog: 4.53 ± 10.29; p = 0.7), the digital system detected more lesions in 22 of 83 of PET+ patients (26.5%) (p = 0.05, 95% CI, 17.9-36.7). In these 22 patients, all lesions detected by the digital PET/CT (and not by the analog PET/CT) were < 10 mm. CONCLUSION: Digital PET/CT offers improved image quality and lesion detection capability over the analog PET/CT in oncological patients, and even better for sub-centimeter lesions.

Influence of antrum size on gastric emptying and weight-loss outcomes after laparoscopic sleeve gastrectomy (preliminary analysis of a randomized trial).

BACKGROUND: Laparoscopic sleeve gastrectomy (LSG) has increased in popularity in recent years as a definitive bariatric procedure. Despite its growing popularity worldwide, the surgical technique is not well standardized. There is a lack of evidence on the matter of the antrum size and its relation to gastric emptying and weight-loss outcomes. The aim of the study is to evaluate the influence of antrum size over gastric emptying and weight-loss outcomes. METHODS: Twenty-five patients were prospectively randomized according to the distance between the first firing and the pylorus: AR group (antrum resection-2 cm from the pylorus) and AP group (antrum preservation-5 cm from the pylorus). Gastric emptying (%GE) was evaluated by a gastric emptying scintigraphy before surgery, 2 months and 1 year after LSG. Antrum volume was measured using a MultiSlice CT Scan performed 2 months and 1 year after surgery. The percent of excess weight loss (%EWL) was calculated after 1 year follow-up. RESULTS: At 2 months after LSG the mean %GE was 69.7 ± 18 in the AR group and 72.8 ± 20 in the AP group (p = 0.69). At 1 year it was 66.5 ± 21 and 74.2 ± 16 in the AR and AP groups, respectively (p = 0.30). A significant accelerated gastric emptying was observed at 2 months (p = 0.025) and at 1 year (p = 0.013) in the AP group. Meanwhile in the AR group this increase was not significant (p = 0.12 at 2 months and p = 0.21 at 1 year). Differences regarding the %EWL between groups were no statistically significant (p = 0.74). CONCLUSIONS: After LSG there is a global tendency to an accelerated gastric emptying, although only significant in the antrum preservation group; however, no differences were observed regarding the %EWL between groups after 1 year follow-up.

Tofacitinib ameliorates inflammation in a rat model of airway neutrophilia induced by inhaled LPS.

BACKGROUND AND PURPOSE: The Janus Kinase (JAK) family mediates the cytokine receptor-induced signalling pathways involved in inflammatory processes. The activation of the signal transducers and activators of transcription (STATs) by JAK kinases is a key point in these pathways. Four JAK proteins, JAK1, JAK2, JAK3 and tyrosine kinase 2 (Tyk2) associate with the intracellular domains of surface cytokine receptors are phosphorylating STATs and modulating gene expression. The aim of this study was to explore the role of JAK inhibition in an acute model of inhaled lipopolysaccharide (LPS)-induced airway inflammation in rats through evaluating the effects of tofacitinib, a marketed pan-JAK inhibitor. Specifically, some pulmonary inflammation parameters were studied and the lung STAT3 phosphorylation was assessed as a target engagement marker of JAK inhibition in the model. EXPERIMENTAL APPROACH: Rats were exposed to an aerosol of LPS (0.1 mg/ml) or phosphate-buffered saline (PBS) during 40 min. Bronchoalveolar lavage fluid (BALF) and lung samples were collected 4 h after PBS or LPS exposure. Neutrophils in BALF were counted and a panel of cytokines were measured in BALF. Phosphorylation of STAT3 was studied in lung homogenates by ELISA and localization of phospho-STAT3 (pSTAT3) in lung tissue was also evaluated by immunohistochemistry. In order to assess the effect of JAK inhibition, tofacitinib was administered 1 h before challenge at doses of 3, 10 and 30 mg/kg p.o. KEY RESULTS: Inhaled LPS challenge induced an augment of neutrophils and cytokines in the BALF as well as an increase in pSTAT3 expression in the lungs. Tofacitinib by oral route inhibited the LPS-induced airway neutrophilia, the levels of some cytokines in the BALF and the phosphorylation of STAT3 in the lung tissue. CONCLUSIONS AND IMPLICATIONS: In summary, this study shows that JAK inhibition ameliorates inhaled LPS-induced airway inflammation in rats, suggesting that at least JAK/STAT3 signalling is involved in the establishment of the pulmonary neutrophilia induced by LPS. JAKs inhibitors should be further investigated as a potential therapy for respiratory inflammatory diseases.

Enhanced cough reflex in a model of bleomycin-induced lung fibrosis in guinea pigs.

Fibrotic lung diseases, such as idiopathic pulmonary fibrosis, are associated with spontaneous dry cough and hypersensitivity to tussive agents. Understanding the pathophysiology driving enhanced cough may help us to define better therapies for patients. We hypothesized that lung fibrosis induced by intratracheal bleomycin would exacerbate the cough reflex induced by tussive agents in guinea pigs. Disease progression in the lungs was characterized at days 1, 7, 14, 21 and 28 after bleomycin administration. Inflammatory and fibrotic markers, as well as neurotrophin levels, were assessed in bronchoalveolar lavage fluid and/or lung tissue. Cough sensitivity to citric acid, capsaicin and allylisothiocyanate was evaluated in conscious animals at days 14 and 21 after bleomycin administration. Pulmonary lesions evolved from an early inflammatory phase (from day 1 to day 7) to a fibrotic stage (between days 14 and 28). Fibrosis was related to increased levels of matrix metalloproteinase-2 in bronchoalveolar lavage fluid (day 21: saline, 0.26 ng/ml; bleomycin, 0.49 ng/ml). At day 14, we also observed increased cough reflexes to citric acid (163%), capsaicin (125%) and allylisothiocyanate (178%). Cough exacerbation persisted, but at a lower extent, by day 21 for capsaicin (100%) and allylisothiocyanate (54%). Moreover, bronchoalveolar lavage fluid concentrations of brain-derived neurotrophic factor, suggested to induce nerve remodelling in chronic cough, were also enhanced (day 1: saline, 14.21 pg/ml; bleomycin, 30.09 pg/ml). In summary, our model of bleomycin-induced cough exacerbation may be a valuable tool to investigate cough hypersensitivity and develop antitussive therapies for fibrotic lung diseases.

Double-stranded RNA evokes exacerbation in a mouse model of corticosteroid refractory asthma.

RNA viruses are a major cause of respiratory infections and are known to exacerbate asthma and other respiratory diseases. Our aim was to test the ability of poly(I:C) (polyinosinic:polycytidylic acid), a viral surrogate, to elicit exacerbation in a model of severe asthma driven by HDM (house dust mite) in FCA (Freund's complete adjuvant). Poly(I:C) was administered intranasally around the HDM challenge in FCA-HDM-sensitized animals. Changes in AHR (airway hyperresponsiveness), BALF (bronchoalveolar lavage fluid) inflammatory infiltrate, HDM-specific immunoglobulins and cytokine/chemokine release were evaluated at different points after the challenge. The effect of oral dexamethasone was also assessed. Exacerbation was achieved when poly(I:C) was administered 24 h before the HDM challenge and was characterized by enhanced AHR and an increase in the numbers of neutrophils, macrophages and lymphocytes in the BALF. Th1, Th2 and Th17 cytokines were also elevated at different time points after the challenge. Peribronchial and alveolar inflammation in lung tissue were also augmented. AHR and inflammatory infiltration showed reduced sensitivity to dexamethasone treatment. We have set up a model that mimics key aspects of viral exacerbation in a corticosteroid-refractory asthmatic phenotype which could be used to evaluate new therapies for this condition.

A novel inhaled Syk inhibitor blocks mast cell degranulation and early asthmatic response.

Spleen tyrosine kinase (Syk) is essential for signal transduction of immunoreceptors. Inhibition of Syk abrogates mast cell degranulation and B cell responses. We hypothesized that Syk inhibition in the lung by inhaled route could block airway mast cells degranulation and the early asthmatic response without the need of systemic exposure. We discovered LAS189386, a novel Syk inhibitor with suitable properties for inhaled administration. The aim of this study was to characterize the in vitro and in vivo profile of LAS189386. The compound was profiled in Syk enzymatic assay, against a panel of selected kinases and in Syk-dependent cellular assays in mast cells and B cells. Pharmacokinetics and in vivo efficacy was assessed by intratracheal route. Airway resistance and mast cell degranulation after OVA challenge was evaluated in an ovalbumin-sensitized Brown Norway rat model. LAS189386 potently inhibits Syk enzymatic activity (IC50 7.2 nM), Syk phosphorylation (IC50 41 nM), LAD2 cells degranulation (IC50 56 nM), and B cell activation (IC50 22 nM). LAS189386 inhibits early asthmatic response and airway mast cell degranulation without affecting systemic mast cells. The present results support the hypothesis that topical inhibition of Syk in the lung, without systemic exposure, is sufficient to inhibit EAR in rats. Syk inhibition by inhaled route constitutes a promising therapeutic option for asthma.

Onset and progression of postmortem histological changes in the central nervous system of RccHan™: WIST rats.

Death initiates a cascade of physiological and biochemical alterations in organs and tissues, resulting in microscopic changes that challenge the histopathological evaluation. Moreover, the brain is particularly susceptible to artifacts owing to its unique composition and its location within the cranial vault. The aim of this study was to compile and illustrate the microscopic changes in the central nervous system (CNS) of rats subjected to delayed postmortem fixation. It also scrutinizes the influence of exsanguination and cooling methods on the initiation and progression of these alterations. Twenty-four Wistar Han outbred rats (RccHan™: WIST) were sacrificed and stored either at room temperature (18-22°C) or under refrigeration (2-4°C). Necropsies were conducted at different time points postmortem (i.e., 0.5 h, 1 h, 4 h, 8 h, 12 h, 24 h, 36 h, 48 h, 7 days and 14 days). Brain sections underwent simultaneous digital evaluation by 14 pathologists until a consensus was reached on terminology, key findings, and intensity levels. Microscopic observations varied among cell types. Glial cells were similarly affected throughout the CNS and showed pericellular halo, chromatin condensation and nuclear shrinkage. Neurons showed two types of postmortem changes as most of them showed progressive shrinkage, cytoplasmic dissolution and karyorrhexis whereas others acquired a dark-neuron-like appearance. Neuronal changes showed marked differences among neuroanatomical locations. Additional postmortem changes encompassed: granulation and microcavitation in neuropil and white matter; retraction spaces; detachment of ependyma, choroid plexus, and leptomeninges. Severity of findings after 48 h at room temperature was higher than after seven days under refrigeration and similar to or slightly lower than after 14 days under refrigeration. No clear differences were observed related to the sex or weight of the animals or their exsanguination status. This work elucidates the onset and progression of autolytic changes in the brains of Wistar Han rats, offering insights to accurately identify and enhance the histopathological evaluation.

Innovative Post-Processing for Complex Geometries and Inner Parts of 3D-Printed AlSi10Mg Devices.

A new technology consisting of new and sustainable chemical polishing treatment for aluminum components with complex shapes, such as heat exchangers, manifolds, busbars, aerospace devices, etc., manufactured by Additive Manufacturing (AM) technologies is described in this paper. This technology will contribute to the development of a more efficient manufacturing process driven by AM, reinforcing the main idea of AM, which is based on reducing the amount of material and achieving cost savings through smart and improved designs. The present study shows a significant reduction in the surface roughness of consolidated AlSi10Mg metal parts manufactured by the SLM technique after carrying out the new chemical polishing post-process investigated in this work. Roughness values have been measured by mechanical and optical profilometry. The results obtained demonstrate the effectiveness of the chemical polishing, decreasing the roughness by up to 40%, being a reproducible and repeatable post-process. The presence of smut as solid residues on such types of chemical treatments has been also analyzed with XRF and ICP-MS techniques. The results obtained show that Si and Mg precipitates are removed from the metal surface at the last step of the investigated post-process. The percentages of the elements decrease from 25.0% to 8.09% Si and from 0.86% to 0.42% Mg, achieving the alloy smut-free composition on the metal surface. Tensile strength measurements have shown that the post-process described not only maintains the mechanical properties of the bulk material but, in comparison with non-post-processed parts, a slight improvement is observed with respect to the initial values, Young modulus (61.1 GPa to final 62.2 GPa), yield strength (from 236.8 to 246.7 MPa), and tensile strength (from 371.9 to 382.5 MPa) is observed, suggesting that the post-process has positive impact on the printed metal part.

Characterization of a model of tracheal plasma extravasation in passively sensitized rats using anti-allergic and anti-inflammatory drugs by oral and intratracheal route.

The aim of the following study was to characterize a passive systemic anaphylaxis rat model of dinitrophenyl (DNP)-induced plasma extravasation in the trachea to determine if the model is appropriate for the evaluation of new drugs targeting airway mast cells by oral and intratracheal (i.t.) route. To this purpose we have used fluticasone and a range of anti-allergic drugs including compounds either active on mast cell activation, such as cromoglycate and the Syk inhibitor R406, or active on mast cell mediators, such as cetirizine and montelukast. To further characterize the model, the effect of fluticasone, cromoglycate and R406 on rat tracheal mast cell degranulation was also assessed histologically. DNP-induced tracheal plasma extravasation was inhibited by cromoglycate (i.v. and i.t.) and R406 (p.o.), but not by fluticasone (i.t.), cetirizine or montelukast (p.o.). Cromoglycate and R406 also showed inhibition of tracheal mast cell degranulation, whereas fluticasone was inactive. These results suggest that the DNP-induced tracheal plasma extravasation model constitutes a useful animal model for the evaluation, by oral and i.t. route, of new anti-allergic drugs intended to target airway mast cells.

Morphofunctional changes underlying intestinal dysmotility in diabetic RIP-I/hIFNß transgenic mice.

The pathogenetic mechanisms underlying gastrointestinal dysmotility in diabetic patients remain poorly understood, although enteric neuropathy, damage to interstitial cells of Cajal (ICC) and smooth muscle cell injury are believed to play a role. The aim of this study was to investigate the morphological and functional changes underlying intestinal dysmotility in RIP-I/hIFNß transgenic mice treated with multiple very low doses of streptozotocin (20 mg/kg, i.p., 5 days). Compared with vehicle-treated mice, streptozotocin-treated animals developed type 1 diabetes mellitus, with sustained hyperglycaemia for 3.5 months, polyphagia, polydipsia and increased faecal output without changes in faecal water content (metabolic cages). Diabetic mice had a longer intestine, longer ileal villi and wider colonic crypts (conventional microscopy) and displayed faster gastric emptying and intestinal transit. Contractility studies showed selective impaired neurotransmission in the ileum and mid-colon of diabetic mice. Compared with controls, the ileal and colonic myenteric plexus of diabetic mice revealed ultrastructural features of neuronal degeneration and HuD immunohistochemistry on whole-mount preparations showed 15% reduction in neuronal numbers. However, no immunohistochemical changes in apoptosis-related markers were noted. Lower absolute numbers of neuronal nitric oxide synthase- and choline acetyltransferase-immunopositive neurons and enhanced vasoactive intestinal polypeptide and substance P immunopositivity were observed. Ultrastructural and immunohistochemical analyses did not reveal changes in the enteric glial or ICC networks. In conclusion, this model of diabetic enteropathy shows enhanced intestinal transit associated with intestinal remodelling, including neuroplastic changes, and overt myenteric neuropathy. Such abnormalities are likely to reflect neuroadaptive and neuropathological changes occurring in this diabetic model.

Long-term impact of COVID-19 associated acute respiratory distress syndrome.

OBJECTIVES: To determine the health status, exercise capacity, and health related quality of life (HRQoL) of COVID-19 associated acute respiratory distress syndrome (ARDS) survivors, 8 months after diagnosis. METHODS: All eligible patients were interviewed and underwent a physical examination, chest X-ray, and 6 min walk test (6MWT). Scales to evaluate post-traumatic stress disorder, depression, anxiety, and HRQoL were applied. RESULTS: Of 1295 patients, 365 suffered ARDS and 166 survived to hospital discharge. Five died after discharge and 48 were lost to follow-up. Of the 113 remaining patients, 81% had persistent symptoms. More than 50% of patients completed less than 80% of the theoretical distance on the 6MWT, 50% had an abnormal X-ray and 93% of patients developed psychiatric disorders. Mean SF-36 scores were worse than in the general population. After multivariate regression analysis, female sex, non-Caucasian race, and Charlson index>2 were independent risk factors for a worse mental health component summary score on the SF-36, and age was associated with a better prognosis. Female sex and chronic obstructive pulmonary disease were independently associated with a worse physical component summary score. CONCLUSION: COVID-19 associated ARDS survivors have long-term consequences in health status, exercise capacity, and HRQoL. Strategies addressed to prevent these sequelae are needed.

Selection of Reference Regions to Model Neurodegeneration in Huntington Disease by 18F-FDG PET/CT Using Imaging and Clinical Parameters.

OBJECTIVE: Normalization to an appropriate reference region in F-FDG PET imaging may enhance diagnostic performance in Huntington disease (HD). We aimed to identify stable brain areas that could be used to model neurometabolic degeneration in HD correlating imaging (SUVrvalues at the basal ganglia [BBGG]) and clinical parameters (disease burden score [DBS]). MATERIALS AND METHODS: We performed brain F-FDG PET/CT in 38 manifest HD patients (meanage ± SD, 54 ± 14.3 years; CAGrepeats ± SD, 44.2 ± 3.1), 20 premanifest HD patients (meanage ± SD, 42.7 ± 11.7 years; CAGrepeats ± SD, 40 ± 3.8), and 18 healthy controls (NC; meanage ± SD, 45 ± 13.2 years). For quantitative analysis, we selected (a) defined reference regions from the Montreal Neurological Institute space atlas (pons, whole cerebellum, cerebral white matter, thalamus, and a pons-cerebellar vermis region of interest), and (b) reference clusters obtained by voxelwise statistical comparison across groups (P < 0.05 FWE; extent voxel threshold k = 200). Each candidate reference region and reference cluster was quantitatively assessed using imaging and clinical parameters. RESULTS: Comparing HD and NC groups, we obtained a reference cluster in the cerebellum, and in temporal and frontal lobes. Comparing manifest HD and premanifest HD patients, we observed reference clusters in the cerebellum, pons, thalamus, parietal lobe, and cuneus. The set of reference regions showed a significant correlation between SUVrvalues at the BBGG and DBS in all HD patients. In premanifest HD patients, the correlation between SUVrvalues at the BBGG and DBS was significant using the pons-cerebellar vermis region of interest, the thalamus as defined reference regions, and the pons and thalamus as reference clusters. In manifest HD patients, the correlation was significant using the temporal and white matter frontal lobe clusters. Variance between SUVrvalues in the set of reference regions and reference clusters was minimal within NC. CONCLUSIONS: The pons may be a stable and reliable region to calculate SUVrvalues to model the neurometabolic degeneration in quantitative F-FDG PET imaging in HD.

PI3K, p38 and JAK/STAT signalling in bronchial tissue from patients with asthma following allergen challenge.

BACKGROUND: Inhaled allergen challenges are often used to evaluate novel asthma treatments in early phase clinical trials. Current novel therapeutic targets in asthma include phosphoinositide 3-kinases (PI3K) delta and gamma, p38 mitogen-activated protein kinase (p38) and Janus kinase/Signal Transducer and Activator of Transcription (JAK/STAT) signalling pathways. The activation of these pathways following allergen exposure in atopic asthma patients it is not known. METHODS: We collected bronchial biopsies from 11 atopic asthma patients at baseline and after allergen challenge to investigate biomarkers of PI3K, p38 MAPK and JAK/STAT activation by immunohistochemistry. Cell counts and levels of eosinophil cationic protein and interleukin-5 were also assessed in sputum and bronchoalvelar lavage. RESULTS: Biopsies collected post-allergen had an increased percentage of epithelial cells expressing phospho-p38 (17.5 vs 25.6%, p = 0.04), and increased numbers of sub-epithelial cells expressing phospho-STAT5 (122.2 vs 540.6 cells/mm2, p = 0.01) and the PI3K marker phospho-ribosomal protein S6 (180.7 vs 777.3 cells/mm2,p = 0.005). Type 2 inflammation was increased in the airways post allergen, with elevated levels of eosinophils, interleukin-5 and eosinophil cationic protein. CONCLUSIONS: Future clinical trials of novel kinase inhibitors could use the allergen challenge model in proof of concept studies, while employing these biomarkers to investigate pharmacological inhibition in the lungs.

Mapping of aggrecan, hyaluronic acid, heparan sulphate proteoglycans and aquaporin 4 in the central nervous system of the mouse.

The extracellular matrix (ECM) of the central nervous system (CNS) is found dispersed in the neuropil or forming aggregates around the neurons called perineuronal nets (PNNs). The ECM mainly contains chondroitin sulphate proteoglycans (CSPG), hyaluronic acid (HA) and tenascin-R. Heparan sulphate proteoglycans (HSPG) can also be secreted in the ECM or be part of the cell membrane. The ECM has a heterogeneous distribution which has been linked to several functions, such as specific regional maintenance of hydrodynamic properties in the CNS, in which aquaporins (AQP) play an important role. AQP are a family of membrane proteins which acts as a water channel and AQP4 is the most abundant isoform in the brain. Nevertheless the importance of these proteins, their distribution and correlation in the whole CNS of mice is only partially known. In the present study, the histochemical and immunohistochemical distribution of PNNs, using Wisteria floribunda agglutinin (WFA), aggrecan, HA, HSPGs and AQP4 is described, and their perineuronal and neuropil staining has been semi-quantitatively evaluated in the whole CNS of mice. The results showed that the aggrecan, HA and HSPGs perineuronal distribution coincided partially and this could be related to ECM functional properties. AQP4 showed a heterogeneous distribution throughout the CNS. In some areas, an inverse correlation between AQP4 and ECM components has been observed, suggesting a complementary role for both in the maintenance of water homeostasis. A common location for AQP4 and HSPGs has also been observed in CNS neuropil.