Impacts of the COVID-19 lockdown measures on coarse and fine atmospheric aerosol particles (PM) in the city of Rome (Italy): compositional data analysis approach.

In the year 2020, Italy faced a pandemic due to the virus SARS-CoV-2 for short COVID-19. Following this pandemic, a national lockdown period was imposed and throughout the year 2020 various measures were taken by the government to limit the mobility of people and contain the mortality associated with COVID-19. In Italy, pandemic measures led to a reduction in anthropogenic activities and provided an unprecedented opportunity to evaluate the possible effects that restrictions on anthropogenic activities may have on the air quality. Two background site (i.e., Cipro and Cinecittà) and a traffic sites (i.e., Corso Francia) were studied in the city of Rome. PM10 and PM2.5 were considered for the years 2019 and 2020. Moreover, the vehicular mobility, the emission classes of the vehicles, and the people mobility were taken into consideration along with meteorological variables. A compositional data analysis was used to evaluate the effect of pandemic measures on the fine- and coarse-size fractions of PM in the three considered sites. The results showed that in the traffic site (i.e., Corso Francia site) in 2020, there was a reduction of fine-size fraction of PM of about 10% when compared to the data of 2019, whereas in the background site (i.e., Cinecittà site) in 2020 there was an increase of fine-size fraction of PM of about 14% when compared to the data of 2019. No variation in the coarse- and fine-size fractions of PM were observed at the background site Cipro. This study showed how, in an urban context, PM can be influenced by strong changes in people's habits and in vehicular mobility such as those recorded during the investigated period and due to pandemic lockdown measures.

Apportioning PM1 in a contrasting receptor site in the Mediterranean region: Aerosol sources with an updated sulfur speciation.

A multi-parametric experimental campaign was performed in Agri Valley (Basilicata, southern Italy) from July 2017 to January 2018. The investigated area, though basically rural and devoted to agricultural activities, hosts a huge on-shore oil reservoir, i.e. Centro Olio Val d'Agri (COVA), bringing substantial environmental modifications and impacts to the district landscape. Daily concentrations of PM1 aerosol samples, Equivalent Black Carbon and number size distributions were evaluated. Chemical aerosol speciation based on elemental and ion analyses were carried out and source apportionment by Positive Matrix Factorization (PMF) was applied to reconstruct PM1 source profile. The most significant emission sources found are torches from the oil treatment facility (37 % w/w), an unresolved factor constituted by soil resuspension, Saharan dust, and biomass burning (24 % w/w), ammonium sulphate (23 % w/w), emissions from the oil desulfurization (Claus process) (13 % w/w), and traffic + road dust (3 % w/w). SEM analysis on PM1 single particles allowed to confirm the finding from PMF including the occurrence of elemental sulfur associated with the Claus process. The novelty of the present study consists in the identification of this latter fingerprint.

A systematic approach for the comparison of PM10, PM2.5, and PM1 mass concentrations of characteristic environmental sites.

This study explores the use of a systematic approach in the comparison of simultaneous measurements of PM10, PM2.5, and PM1 mass concentrations using Aitchison geometry. Three case studies in three different Asian cities where the PM coarse, fine, and ultrafine size fraction prevail were investigated and the data was displayed using a dedicated triangular diagram. Simultaneous size-segregated PM measurements, for each case study, were assessed in terms of PM ratios and PM10 levels and were compared to similar measurements reported in literature. Non-central chi-squared distribution quantiles, for each case study, were evaluated and used to investigate the degree of similarity between simultaneous size-segregated PM ratios. Likewise, a comparative number k was used to show the proportion between PM10 levels. The issues relating to the location of the simultaneous size-segregated PM ratios on the triangular diagram were examined and the effects of the non-centrality parameter λ on PM comparison were indicated. The results show that the proposed systematic approach can estimate an explorative quantile (i.e., 2.5%) within which the simultaneous size-segregated PM measurements from one site can be compared with simultaneous size-segregated PM measurements from other sites reported in literature highlighting the existence of possible similarities or correspondences in the kind of sources influencing the PM.

Trace elements and human health risks assessment of finer aerosol atmospheric particles (PM1).

The present study investigated PM1 (aerosol particles with an aerodynamic diameter ≤ 1.0 µm) mass concentrations and sixteen (Al, Ca, Cd, Cr, Cu, Fe, K, Li, Mg, Mn, Na, Ni, Pb, S, Ti, and Zn) PM1-related trace elements. PM1 samples were collected in an anthropized area of international attention close to oil/gas pre-treatment plants in Agri Valley (Southern Italy). The PM1 mass concentrations varied from 3 to 16 µg/m3. The decreasing pattern of the trace element concentrations was S > Ca > Na > K ≈ Mg ≈ Fe> Al > Li > Cr > Zn > Ti> Cu > Ni ≈ Mn > Pb ≈ Cd. Anthropogenic local emissions such as biomass burning, vehicular traffic, and industrial sources mainly related to oil/gas pre-treatment plants were identified by the principal component analysis. Further, air mass back-trajectory analyses suggest an important contribute to the long-range transport on PM1 at Agri Valley. The carcinogenic (Cd, Cr(VI), Ni, and Pb) and non-carcinogenic (Cd, Cr(VI), Cu, Mn, Ni, Pb, and Zn) health risks both for children and for adults were assessed using the United State Environmental Protection Agency (USEPA) methods considering inhalation, ingestion, and dermal contact pathway. Chromium (VI) posed the highest carcinogenic risk for both children and adults. The integrated carcinogenic risks were respectively 3.45 × 10-5 and 1.38 × 10-4 for children and adults indicating that attention should be paid for carcinogenic health effects. Nickel posed the highest non-carcinogenic risk for children through inhalation pathway. The integrated non-carcinogenic risk showed a value higher than 1 highlighting that Cd, Cr(VI), Cu, Mn, Ni, Pb, and Zn may cause cumulative non-carcinogenic health effect for children from inhalation exposure.

3'-deoxy-3'-18F-fluorothymidine PET/CT to guide therapy with epidermal growth factor receptor antagonists and Bcl-xL inhibitors in non-small cell lung cancer.

UNLABELLED: Epidermal growth factor receptor (EGFR) mutational status, activation of downstream signaling, and effective apoptotic cascade are all factors that may affect the tumor response to EGFR tyrosine kinase inhibitors (TKIs) in non-small cell lung cancer (NSCLC). Here we test whether 3'-deoxy-3'-(18)F-fluorothymidine ((18)F-FLT) PET/CT can provide clues for the selection of patients with NSCLC as candidates for treatment with reversible and irreversible EGFR TKIs or combination treatment with Bcl-x(L) inhibitors. METHODS: HCC827, H1975, and H1650 NSCLC cells were subcutaneously injected into flanks of nude mice. Tumor-bearing animals were treated daily for 3 d by oral gavage with erlotinib at 50 and 150 mg/kg, CL-387,785 (an irreversible EGFR TKI) at 50 mg/kg, WZ4002 (a more potent irreversible EGFR TKI) at 25 and 50 mg/kg, ABT-263 (a Bcl-x(L) inhibitor) at 6.25 mg/kg, and a combination of erlotinib (50 mg/kg) and ABT-263 (6.25 mg/kg). Imaging studies were performed before and after 3 d of treatment by intravenous injection of 7.4 MBq of (18)F-FLT and small-animal PET/CT of animals at 1 h after injection. Quantitative analysis of reconstructed images of baseline and posttreatment scans was performed, and the percentage change in (18)F-FLT uptake in each animal was determined. Tumor sections were tested for Ki67 immunostaining and the percentage of apoptotic cells. RESULTS: Sensitive tumors (HCC827) showed mean decreases in (18)F-FLT uptake of 45% and 28% with high- and low-dose regimens of erlotinib, respectively. Resistant NSCLC cells bearing a T790M mutation (H1975) showed mean increases in (18)F-FLT uptake of 27% and 33% with high and low doses of erlotinib, respectively. Treatment with CL-387,785, low-dose WZ4002, and high-dose WZ4002 caused mean decreases in tracer uptake of 21%, 26%, and 36%, respectively. NSCLC cells that were resistant because of dysregulation of Bcl-2 family members (H1650) showed mean reductions in (18)F-FLT uptake of 49% and 23% with high and low doses of erlotinib, respectively, whereas the addition of ABT-263 did not affect tracer uptake but significantly increased the percentage of apoptotic cells in tumor sections. CONCLUSION: PET/CT with (18)F-FLT may contribute to the selection of patients who may benefit from treatment with reversible and irreversible EGFR TKIs and may provide clues about which patients with NSCLC may be candidates for combination treatment with erlotinib and Bcl-x(L) inhibitors.

Ultraviolet radiation increases sensitivity to pesticides: synergistic effects on population growth rate of Daphnia magna at low concentrations.

In the present study we aimed to investigate whether UV-B radiation can exacerbate effects of pesticides fenoxycarb, pirimicarb, and tebufenpyrad on the survival, reproduction, and population growth rate of the standard test species Daphnia magna. We applied sublethal pesticides' concentrations and UV doses and observed no effects on survival. However, we observed synergistic effects of UV and pesticides on both cumulative reproduction and population growth rate (21 days) for fenoxycarb (100 µg/L) and pirimicarb (10 µg/L), but a less-than-additive effect for tebufenpyrad (5-10 µg/L). In the series exposed to UV and fenoxycarb or pirimicarb, the population growth rate dropped down to 0.1, while in the control series it was around 0.3. The results indicate that concentrations of some toxicants that are nontoxic in standard tests can cause harmful population-level effects when combined with UV.

Enhancement of reaction conditions for the radiolabelling of DOTA-peptides with high activities of yttrium-90.

UNLABELLED: Peptide receptor radionuclide therapy (PRRT) has recently expanded due to radiolabelling of DOTA-peptides, such as the somatostatin analogues [DOTA(0), Tyr(3)]octreotate (DOTATATE). The achievement of high specific activities during procedures has been indicated as the critical factor to consent effective therapy. Several radiochemical factors may negatively impact reaction procedures such as pH, temperature and time of reaction. Our study was undertaken to explore the influence of radiochemical parameters, such as time of incubation, on reaction kinetics during the radiolabelling of DOTATATE with (90)Y. METHODS: Forty-five radiolabelling procedures were carried out using small volumes of yttrium-90, typically 60-78 µL. At nearly constant pH and temperature two different settings of radiolabelling procedures were implemented, removing the products from the heating water bath approximately after 30 min (group E, early; n=20) and after 39 min (group L, later; n=25). Quality controls were performed by means of both high-performance liquid chromatography (HPLC) and thin-layer chromatography (TLC). RESULTS: Reaction kinetics for (90)Y were found to a provide suitable percentage of incorporation at pH 4.5 for both groups. Reaction temperature was not different between groups E and L. A significant difference was found between the two groups in radiochemical yield, which was 95.6% ± 0.8 for group E and 98.2% ± 1.1 for group L (p<0.0001). The specific activity of the final product was 46.9 MBq/nmol. CONCLUSION: In order to achieve optimal specific activities, pH, temperature and time of reaction necessitate careful evaluation and setting. A statistically significant difference in labelling yield was found between a set of procedures completed at 39 min as compared to that executed at 30 min, keep the reaction pH and temperature constant.

Detection of colo-rectal liver metastases: prospective comparison of contrast enhanced US, multidetector CT, PET/CT, and 1.5 Tesla MR with extracellular and reticulo-endothelial cell specific contrast agents.

BACKGROUND: To compare contrast-enhanced US (CE-US), multidetector-CT (MDCT), 1.5 Tesla MR with extra-cellular (Gd-enhanced) and intracellular (SPIO-enhanced) contrast agents and PET/CT, in the detection of hepatic metastases from colorectal cancer. MATERIALS AND METHODS: A total of 34 patients with colo-rectal adenocarcinoma underwent preoperatively CE-US, MDCT, Gd- and SPIO-enhanced MR imaging (MRI), and PET/CT. Each set of images was reviewed independently by two blinded observers. The ROC method was used to analyze the results, which were correlated with surgical findings, intraoperative US, histopathology, and MDCT follow-up. RESULTS: A total of 57 hepatic lesions were identified: 11 hemangiomas, 29 cysts, 1 focal fatty liver, 16 metastases (dimensional distribution: 5/16 < 5 mm; 3/16 between 5 mm and <10 mm; 8/16 ≥ 10 mm). Six of 34 patients were classified as positive for the presence of at least one metastasis. Considering all the metastases and those ≥ 10 mm, ROC areas showed no significant differences between Gd- and SPIO-enhanced MRI, which performed significantly better than the other modalities (P < 0.05). Considering the lesions <10 mm, ROC areas showed no significant differences between all modalities; however MRI presented a trend to perform better than the other techniques. Considering the patients, ROC areas showed no significant differences between all the modalities; however PET/CT seemed to perform better than the others. CONCLUSIONS: Gd- and SPIO-enhanced MRI seem to be the most accurate modality in the identification of liver metastases from colo-rectal carcinoma. PET/CT shows a trend to perform better than the other modalities in the identification of patients with liver metastases.

Assessment of metabolic response to radioimmunotherapy with 90Y-ibritumomab tiuxetan in patients with relapsed or refractory B-cell non-Hodgkin lymphoma.

PURPOSE: To prospectively compare the assessment of metabolic response to yttrium 90 ((90)Y)-ibritumomab tiuxetan radioimmunotherapy (RIT) by using fluorine 18 ((18)F) fluorodeoxyglucose (FDG) combined positron emission tomographic-computed tomographic (PET/CT) imaging at 2 and 6 months to determine the most appropriate time to detect therapeutic response in refractory non-Hodgkin lymphoma (NHL) patients treated with RIT. MATERIALS AND METHODS: The ethical committee of the university approved the protocol and all patients signed informed consent. Twenty-three consecutive patients (10 women, 13 men; mean age, 51.8 years +/-7.3 [standard deviation]) treated by using RIT for relapsed or refractory follicular NHL were enrolled. For all patients, (18)F FDG PET/CT scanning was performed at baseline and at 2 and 6 months after RIT. Response was assessed by using the International Workshop Criteria (IWC) and revised criteria (IWC + PET) as well as the criteria of the European Organization for Research and Treatment of Cancer. One-way analysis of variance for repeated measures, receiver operator curve analysis, and Kaplan-Meier curves were used for statistical analysis. RESULTS: PET/CT performed at 2 months revealed complete (n = 12) or partial (n = 4) metabolic response in 16 of 23 patients with complete or partial clinical response. These findings were all confirmed at 6-month scanning. PET/CT indicated refractory or persistent disease at 2 and 6 months in the remaining seven patients. Better overall survival was observed for patients with a reduction in the maximum standard uptake value of 49% or higher (both at 2 and 6 months after RIT) when compared with those with a decrease of less than 49% (P < .05). CONCLUSION: Early assessment of response to RIT by using PET/CT might be useful in the identification of patients needing additional therapeutic strategies.

Imaging of alpha(v)beta(3) expression by a bifunctional chimeric RGD peptide not cross-reacting with alpha(v)beta(5).

PURPOSE: To test whether a novel bifunctional chimeric peptide comprising a cyclic Arg-Gly-Asp pentapeptide covalently bound to an echistatin domain can discriminate alpha(v)beta(3) from alpha(v)beta(5) integrin, thus allowing the in vivo selective visualization of alpha(v)beta(3) expression by single-photon and positron emission tomography (PET) imaging. EXPERIMENTAL DESIGN: The chimeric peptide was preliminarily tested for inhibition of alpha(v)beta(3)-dependent cell adhesion and competition of 125I-echistatin binding to membrane of stably transfected K562 cells expressing alpha(v)beta(3) (Kalpha(v)beta(3)) or alpha(v)beta(5) (Kalpha(v)beta(5)) integrin. The chimeric peptide was then conjugated with diethylenetriaminepentaacetic acid and labeled with 111In for single-photon imaging, whereas a one-step procedure was used for labeling the full-length peptide and a truncated derivative, lacking the last five C-terminal amino acids, with 18F for PET imaging. Nude mice bearing tumors from Kalpha(v)beta(3), Kalpha(v)beta(5), U87MG human glioblastoma, and A431 human epidermoid cells were subjected to single-photon and PET imaging. RESULTS: Adhesion and competitive binding assays showed that the novel chimeric peptide selectively binds to alpha(v)beta(3) integrin and does not cross-react with alpha(v)beta(5). In agreement with in vitro findings, single-photon and PET imaging studies showed that the radiolabeled chimeric peptide selectively localizes in tumor xenografts expressing alphavbeta3 and fails to accumulate in those expressing alpha(v)beta(5) integrin. When 18F-labeled truncated derivative was used for PET imaging, alphavbeta3- and alpha(v)beta(5)-expressing tumors were visualized, indicating that the five C-terminal amino acids are required to differentially bind the two integrins. CONCLUSION: Our findings indicate that the novel chimeric Arg-Gly-Asp peptide, having no cross-reaction with alphavbeta5 integrin, allows highly selective alphavbeta3 expression imaging and monitoring.

Fully automated synthesis procedure of 4-[18F]fluorobenzaldehyde by commercial synthesizer: amino-oxi peptide labelling prosthetic group.

Automatic synthesis of 4-[18F]fluorobenzaldehyde has been developed by a commercially available TRACERlab FX(F-N) synthesis module to be used as prosthetic group for amino-oxy functionalized peptide labelling in clinical routine application. In addition a handmade purification device (HPD) has been setup to perform automatic cartridge purification as well as to back-up the reactor where one-pot synthesis is not applicable. Cartridges for solid phase extraction such as C18, C8, phenyl has been tested to best perform purification as well as activity recovery. Radiochemical yield (RCY) at end of synthesis (EOS) was in average 67% after about 45 min (90% decay corrected at EOB). The RCY of the entire procedure was 54% with a radiochemical purity above 99%.

Accuracy of sonographic volume measurements of kidney transplant.

PURPOSE: Sonographic measurement of renal volume is one of the parameters used in the diagnosis of renal transplant dysfunction and in follow-up of patients with renal transplant. The aim of this study was to compare the prolate ellipsoid formula with a new formula in calculating the volume of a transplanted kidney. METHODS: The renal volumes in 24 patients with a stable renal transplant were determined sonographically with the ellipsoid formula and via helical CT with the voxel-count method, which is the gold standard. A new formula that uses renal length and the cross-sectional area at the maximum transverse section has been evaluated in a small series of transplanted kidneys. RESULTS: Renal volume was underestimated with the sonographic ellipsoid formula and the new formula. The new formula yielded the lowest underestimation of the mean renal volume, and the measurements obtained with it were not significantly different from those obtained with CT. CONCLUSIONS: The use of sonography is appropriate for accurate calculation of renal volume, and the new formula that uses only 2 ultrasound parameters best represents the volume of a renal transplant.