Quantifying changes in ambient NOx, O3 and PM10 concentrations in Austria during the COVID-19 related lockdown in spring 2020

During spring 2020, unprecedented changes in local and regional emissions have occurred around the globe due to governmental restrictions associated with COVID-19. Many European countries including Austria issued partial curfews or stay-at-home order policies, which have impacted ambient air quality through reductions in non-essential transportation and energy consumption of industrial sites and work places. Here, we analyse the effect of these measures on ambient concentrations of nitrogen oxides (NO_x), ozone (O₃) and particulate matter (PM₁₀) during the first nationwide lockdown in Austria (16.03.2020 to 14.04.2020). To ensure a robust analysis, the Austrian domain is divided into four individual subsectors contingent on regional climate. For air quality analysis a novel method is applied for filtering days with comparable weather conditions during the 2020 lockdown and spring 2017 to 2019. In general, our analysis shows decreasing pollutant concentrations, although in magnitude dependent on pollutant and regional subdomain. Largest reductions are found for NO_x reaching up to −68% at traffic sites reflecting the substantial decrease in non-essential transport. Changes in the O₃ concentrations at background sites show a rather weak response to NO_x declines varying between roughly −18 to +8% for both the median and the upper tail of the distribution. Occasional site level increases in O₃ concentrations can be attributed to comparably weak titration during night-time. PM₁₀ concentrations show the smallest response among air pollutants, attributable to manifold precursor sources not affected by the lockdown measures. However, our analysis indicates also a shift of PM₁₀ distributions at traffic sites closer to distributions observed at background sites.

Antiemetic Prophylaxis with Fosaprepitant and 5-HT3-Receptor Antagonists in Pediatric Patients Undergoing Autologous Hematopoietic Stem Cell Transplantation

Background

High-dose myeloablative conditioning prior to autologous hematopoietic stem cell transplantation (autoHSCT) in pediatric patients is usually highly emetogenic. The antiemetic neurokinin-1 receptor antagonist fosaprepitant was safe and effective in children receiving highly emetogenic chemotherapy. Data on fosaprepitant during autoHSCT in children are currently not available.

Methods

A total of 35 consecutive pediatric patients, who received an antiemetic prophylaxis with fosaprepitant (4 mg/kg; single dose, max. 1 x 150 mg/kg BW) and ondansetron (24-hours continuous infusion; 8–32 mg/24h) or granisetron (2 x 40 µg/kg∙d⁻¹) during highly emetogenic conditioning chemotherapy before autoHSCT were retrospectively analyzed, and their results were compared with a control group comprising 35 consecutive pediatric patients, who received granisetron or ondansetron only. The antiemetic efficacy and the safety of the two prophylaxis regimens were compared with respect to three time periods after the first chemotherapy administration (0–24h, >24–120h, >120–240h).

Results

Clinical adverse events and clinically relevant increases/decreases of laboratory markers were similarly low and did not significantly differ between the two study groups (p>0.05). The registered number of vomiting events was significantly higher in the control group in the time periods of 0–24h (64 vs 22 events; p<0.01), >24–120h (135 vs 78 events; p<0.0001), >120–240h (268 vs 105 events; p<0.0001), and the whole observation period 0–240h (467 vs 205 events; p<0.0001). The percentage of patients experiencing vomiting was higher in the control group during the time period of >24–120h (100% vs 74.3%) but not the other analyzed time periods (p>0.05).

Conclusion

The fosaprepitant-based antiemetic prophylaxis was safe, well tolerated and significantly reduced vomiting in children undergoing highly emetogenic chemotherapy prior to autoHSCT. Prospective randomized trials are necessary to confirm these results.

Cathepsin S is associated with degradation of collagen I in abdominal aortic aneurysm

BACKGROUND

Cathepsins have been described in the pathogenesis of abdominal aortic aneurysm (AAA), their exact role, especially in collagen degradation, is still unclear. The aim of the present study was therefore to analyse relevant cathepsins in human AAA tissue samples in relation to collagen I, III, and their degradation products.

MATERIALS AND METHODS

Samples from 37 AAA patients obtained from elective open surgical repair and eight healthy non-aneurysmatic aortas from kidney donors were included. Expression of cathepsins B, D, K, L, S, cystatin C, collagen I and III, their degraded products C-Telopeptide of type 1 and 3 collagen (CTX-I, CTX-III), cellular markers for leukocytes (CD45), T cells (CD3), macrophage scavenger receptor-1 (MSR-1), synthetic, and contractile smooth muscle cells (SMCs) (smoothelin: SMTH, collagen I and III, myosin heavy chain: MHC, embryonic smooth muscle myosin heavy chain: SMemb) were determined at messenger RNA (mRNA) level, using SYBRGreen-based quantitative PCR and at protein level using enzyme-linked immunosorbent assay (ELISA).

RESULTS

Expression of cathepsins B, D, L, and S at mRNA level was significantly elevated in AAA compared to control aorta (1.7-fold, p = 0.025; 2.5-fold, p = 0.002; 2.6-fold, p = 0.034; and 7.0-fold, p = 0.003). Expression of cathepsin S correlated significantly with leukocytes and macrophages (ρ = 0.398, p = 0.033 and ρ = 0.422, p = 0.020), synthetic SMCs were significantly associated with cathepsins B, D, and L (ρ = 0.522, p = 0.003; ρ = 0.431, p = 0.015 and ρ = 0.467, p = 0.008). At protein level, cathepsins B and S were elevated in AAA compared to controls (5.4-fold, p = 0.001 and 7.3-fold, p < 0.001). Significant correlations were observed between collagen I, its degraded product, and cathepsin S (r = -0.350, p = 0.034 and r = +0.504, p < 0.001). Expression of cathepsin B was associated with SMCs, expression of cathepsin S with inflammatory cells.

CONCLUSIONS

Particularly cathepsin S was associated with the degradation product of collagen I and thus might be involved in the progression of AAA. Furthermore, cathepsin S correlated with inflammatory cells.

Association of Matrix Metalloproteinase Levels with Collagen Degradation in the Context of Abdominal Aortic Aneurysm

OBJECTIVE/BACKGROUND

Matrix metalloproteinases (MMPs) have already been identified as key players in the pathogenesis of abdominal aortic aneurysm (AAA). However, the current data remain inconclusive. In this study, the expression of MMPs at mRNA and protein levels were investigated in relation to the degradation of collagen I and collagen III.

METHODS

Tissue samples were obtained from 40 patients with AAA undergoing open aortic repair, and from five healthy controls during kidney transplantation. Expression of MMPs 1, 2, 3, 7, 8, 9, and 12, and tissue inhibitor of metalloproteinase (TIMP)1, and TIMP2 were measured at the mRNA level using quantitative reverse transcription polymerase chain reaction. At the protein level, MMPs, collagen I, and collagen III, and their degradation products carboxy-terminal collagen cross-links (CTX)-I and CTX-III, were quantified via enzyme linked immunosorbent assay. In addition, immunohistochemistry and gelatine zymography were performed.

RESULTS

In AAA, significantly enhanced mRNA expression was observed for MMPs 3, 9, and 12 compared with controls (p ≤ .001). MMPs 3, 9, and 12 correlated significantly with macrophages (p = .007, p = .018, and p = .015, respectively), and synthetic smooth muscle cells with MMPs 1, 2, and 9 (p = .020, p = .018, and p = .027, respectively). At the protein level, MMPs 8, 9, and 12 were significantly elevated in AAA (p = .006, p = .0004, and p < .001, respectively). No significant correlation between mRNA and protein was observed for any MMP. AAA contained significantly reduced intact collagen I (twofold; p = .002), whereas collagen III was increased (4.6 fold; p < .001). Regarding degraded collagen I and III relative to intact collagens, observations were inverse (1.4 fold increase for CTX-1 [p < .001]; fivefold decrease for CTX-III [p = .004]). MMPs 8, 9, and 12 correlated with collagen I (p = .019, p < .001, and p = 0.003, respectively), collagen III (p = .015, p < .001, and p < .001, respectively), and degraded collagen I (p = .012, p = .049, and p = .001, respectively).

CONCLUSION

No significant relationship was found between mRNA and protein and MMP levels. MMPs 9 and 12 were overexpressed in AAA at the mRNA and protein level, and MMP-8 at the protein level. MMP-2 was detected in synthetic SMCs. Collagen I and III showed inverse behaviour in AAA. In particular, MMPs 8, 9, and 12 appear to be associated with collagen I, collagen III, and their degradation products.

Highly variable clinical phenotype of carbamylphosphate synthetase 1 deficiency in one family: an effect of allelic variation in gene expression?

Deficiency of the urea cycle enzyme carbamylphosphate synthetase 1 (CPS1) causes hyperammonemia with a vast range of clinical severity from neonatal onset with early lethality to onset after age 40 with rare episodes of hyperammonemic confusion. The cause for this variability is not understood. We report two patients from one family with highly divergent clinical course, one presenting neonatally with a fatal form and the other at age 45 with benign diet-responsive disease. The patients are compound heterozygous for two mutations of the CPS1 gene, c.3558 + 1G > C and c.4101 + 2T > C. The haplotypes containing each mutation are identical between the two patients, as are the sequences of CPS1 exons and flanking introns. Transcriptional experiments show that the abnormal CPS1 transcripts generated by both mutations are identical in these two patients. We characterize promoter and enhancer sequences of the CPS1 gene and find also in these regions no sequence differences between patients. Finally, we perform cloning experiments and find that in the neonatal-onset case, clones of messenger RNA (mRNA) expressed from the allele carrying the c.4101 + 2T > C mutation are threefold more than clones of mRNA from the allele with the c.3558 + 1G > C mutation, whereas in the adult-onset case the two types of clones are equal, indicating skewed expression towards the c.4101 + 2T > C allele in the neonatal case. Although we are yet to understand the mechanism of this differential expression, our work suggests that allelic imbalance may explain clinical variability in CPS1 deficiency in some families.

Intravascular ultrasonography of an adolescent boy with a coronary artery aneurysm due to Kawasaki disease

A 14-year-old boy developed coronary aneurysms during the course of Kawasaki disease. The vessel wall morphology of the coronary arteries was assessed by intravascular ultrasound imaging (IVUS). There was intimal thickening proximal to, within, and distal to a large coronary aneurysm in the left anterior descending coronary artery only 18 months after the acute onset of Kawasaki disease. Intimal thickening without calcification is a new IVUS finding within a persistent coronary aneurysm. It may indicate that the healing process, via cell proliferation is continuing, with the risk of causing a stenosis.