Comparison of dimension reduction techniques applied to the analysis of airborne radionuclide activity concentration

Temporal variation of airborne radionuclide activity concentration is highly influenced by several meteorological parameters. A traditional key tool to perform a combined analysis on these data is Principal Component Analysis (PCA), a linear dimensionality reduction technique that prioritizes the conservation of the data set global structure. While it reveals important information regarding the correlation among the considered variables, the obtained visual representations do not usually allow to clearly discern different clusters of states with common properties. The main goal of this study is applying two recently introduced non linear dimensionality reduction techniques, t-distributed Stochastic Neighbor Embedding (t-SNE) and Uniform Manifold Approximation and Projection (UMAP) to a data set composed by ⁷Be and gross beta (A_β) activity concentration and other meteorological data gathered in Mallorca (Spain) between 2004 and 2014. Compared to PCA, both algorithms reveal more details on the local structure of the data set. UMAP allows to clearly identify data clusters with different characteristics that are not clearly identified with the alternative techniques.

Effects of Drought on Mortality in Macro Urban Areas of Brazil Between 2000 and 2019

A significant fraction of Brazil's population has been exposed to drought in recent years, a situation that is expected to worsen in frequency and intensity due to climate change. This constitutes a current key environmental health concern, especially in densely urban areas such as several big cities and suburbs. For the first time, a comprehensive assessment of the short-term drought effects on weekly non-external, circulatory, and respiratory mortality was conducted in 13 major Brazilian macro-urban areas across 2000-2019. We applied quasi-Poisson regression models adjusted by temperature to explore the association between drought (defined by the Standardized Precipitation-Evapotranspiration Index) and the different mortality causes by location, sex, and age groups. We next conducted multivariate meta-analytical models separated by cause and population groups to pool individual estimates. Impact measures were expressed as the attributable fractions among the exposed population, from the relative risks (RRs). Overall, a positive association between drought exposure and mortality was evidenced in the total population, with RRs varying from 1.003 [95% CI: 0.999-1.007] to 1.010 [0.996-1.025] for non-external mortality related to moderate and extreme drought conditions, from 1.002 [0.997-1.007] to 1.008 [0.991-1.026] for circulatory mortality, and from 1.004 [0.995-1.013] to 1.013 [0.983-1.044] for respiratory mortality. Females, children, and the elderly population were the most affected groups, for whom a robust positive association was found. The study also revealed high heterogeneity between locations. We suggest that policies and action plans should pay special attention to vulnerable populations to promote efficient measures to reduce vulnerability and risks associated with droughts.

Same-day air pollution and ABCDE stress echo results: nitrogen dioxide increases vulnerability to pulmonary congestion

Funding Acknowledgements

Type of funding sources: None.

OnBehalf

StressEcho 2030 study group

Background

Air pollution affects same-day hospital admissions for acute coronary syndromes, decompensated heart failure and arrhythmias. The present study hypothesis is that air pollution also may affect results of comprehensive cardiac functional testing unmasking a pre-clinical vulnerability.

Aim

To assess the effects of air pollution on stress echocardiography (SE) performed with ABCDE protocol

Methods

We enrolled 1292 patients with chronic coronary syndromes referred for clinically-driven dipyridamole ABCDE-SE (score results from 0= all parameters normal, to 5, all abnormal). Same day values of 5 pollutants were obtained on the same morning of testing (average of 4 hours) from publicly available data sets of regional authority of environmental protection. Air pollution score (APS) of 5 items included fine (PM 2.5) and <10 µm diameter particulate matter, ozone (O3), sulfur dioxide and nitrogen dioxide (NO2). According to predetermined, internationally established thresholds, APS ranged from 0 (all parameters normal or near normal, index value ≤3 in the 1 to 10 scale of UK government air quality index 2014) to 5 (all parameters abnormal).

Results

There was no significant correlation (r=-0.032, p = 0.276) between SE score (0.82 ± 1.08) and APS (1.96 ± 1.09). When individual pollutants were evaluated with individual items (from A to E) of SE score, NO2 concentration was correlated with rest (r=.089; p = 0.001) and peak stress B-lines in step B (r=.099; p < 0.001). Patients with abnormal (> 2) B-lines at peak stress (n = 247) were compared with those with normal (≤ 1) response (n= 1, 045). B-liners showed higher values of same-day NO2 (median value 23.1 [I.Q. range 16.2-31.0] vs 19.7 [12.5-27.4] µg/m3, p< 0.001) and PM 2.5 (22.0 [9.1-23.5] vs 17.6 [8.6-22.2] µg/m3, p< 0.001), with lower values of O3, a secondary pollutant destroyed by NO2 (44.9 [26.7-59.5] vs 48.4 [28.5-67.4] µg/m3, p= 0.040). At multivariable logistic regression analysis (Figure), NO2 predicted stress B-lines with age, hypertension, diabetes, and reduced (< 50%) ejection fraction.

Conclusion Air pollution may modulate cardiac functional testing results. Higher concentration of NO2 and PM 2.5 are associated with more frequent pulmonary congestion mirrored by B-lines at rest and during stress. The increased inflammatory stress mediated by NO2 and PM 2.5 may increase the permeability of the alveolar capillary barrier to any given rise in pulmonary wedge pressure. Abstract table

Evaluation of COVID-19 impact on DELAYing diagnostic-therapeutic pathways of lung cancer patients in Italy (COVID-DELAY study): fewer cases and higher stages from a real-world scenario

Introduction

COVID-19 has disrupted the global health care system since March 2020. Lung cancer (LC) patients (pts) represent a vulnerable population highly affected by the pandemic. This multicenter Italian study aimed to evaluate whether the COVID-19 outbreak had an impact on access to cancer diagnosis and treatment of LC pts compared with pre-pandemic time.

Methods

Consecutive newly diagnosed LC pts referred to 25 Italian Oncology Departments between March and December 2020 were included. Access rate and temporal intervals between date of symptoms onset and diagnostic and therapeutic services were compared with the same period in 2019. Differences between the 2 years were analyzed using the chi-square test for categorical variables and the Mann–Whitney U test for continuous variables.

Results

A slight reduction (−6.9%) in newly diagnosed LC cases was observed in 2020 compared with 2019 (1523 versus 1637, P = 0.09). Newly diagnosed LC pts in 2020 were more likely to be diagnosed with stage IV disease (P < 0.01) and to be current smokers (someone who has smoked more than 100 cigarettes, including hand-rolled cigarettes, cigars, cigarillos, in their lifetime and has smoked in the last 28 days) (P < 0.01). The drop in terms of new diagnoses was greater in the lockdown period (percentage drop −12% versus −3.2%) compared with the other months included. More LC pts were referred to a low/medium volume hospital in 2020 compared with 2019 (P = 0.01). No differences emerged in terms of interval between symptoms onset and radiological diagnosis (P = 0.94), symptoms onset and cytohistological diagnosis (P = 0.92), symptoms onset and treatment start (P = 0.40), and treatment start and first radiological revaluation (P = 0.36).

Conclusions

Our study pointed out a reduction of new diagnoses with a shift towards higher stage at diagnosis for LC pts in 2020. Despite this, the measures adopted by Italian Oncology Departments ensured the maintenance of the diagnostic-therapeutic pathways of LC pts.

•

The COVID-19 outbreak had an impact on access to lung cancer (LC) diagnosis and treatment.

•

A slight reduction (−6.9%) in newly diagnosed LC cases was observed in 2020 compared with 2019.

•

Newly diagnosed LC pts in 2020 were more likely to be diagnosed with stage IV disease.

•

The Italian Oncology Departments ensured the maintenance of the diagnostic-therapeutic pathways of LC pts.

•

A reverse migration from high-volume to low-volume cancer centers was noted during the pandemic.

Design, Development and Validation of a Knee Brace to Standardize the US Imaging Evaluation of Knee Osteoarthritis

Objective: A repeatable and reliable follow-up of knee injuries would be desirable to prevent delayed diagnosis and to monitor the efficacy of the applied treatment over time. Ultrasound (US) techniques are an attractive option to this purpose, since they are safe, low-cost and non-invasive. However, its use in the clinical practice is limited by the high dependency on the operator’s experience. Hence, the objective of this study is to provide a standardization of the US image acquisition process for knee osteoarthritis (OA) allowing an extended clinical use of US technologies in this domain. Methods: Clinical specifications were provided by expert musculoskeletal radiologists thus identifying the subject poses and the US probe positions needed to evaluate the cartilage structure, signs of synovitis and joint effusion. Such considerations were used to derive the technical requirements needed for the development of a wearable brace equipped with specific openings to guide the correct placement of the probe. The feasibility of the developed wearable brace was tested on three healthy volunteers, which were asked to acquire informative US images, similar to the reference images performed by the musculoskeletal radiologist. Results: Thanks to the knee brace, the untrained subjects were able to self-acquire informative B-mode images comparable to the corresponding images acquired by an expert clinician. Discussion/Conclusion: The use of a knee brace intended for knee OA US diagnosis demonstrated the possibility to standardize the acquisition protocol and make its application achievable also for untrained subjects, representing a key step toward tele-ultrasonography.

Sick leave request following anti-COVID-19 vaccine administration is low among healthcare workers: results from a retrospective cross-sectional monocentric study

OBJECTIVE

Anti-COVID-19 vaccines were mainly associated with non-serious adverse events (AEs), whose prevalence was reported to be up to 70% in healthcare workers (HCWs). This may lead to sick leave requests, but this impact has never been quantified. This study aimed to investigate the absence from work among HCWs following anti-COVID-19 vaccination. Its association with age and previous COVID-19 infection was also assessed.

PATIENTS AND METHODS

This is a retrospective observational cross-sectional study on administrative data about sick leave requests after anti-COVID-19 vaccination. All the HCWs employed at the Niguarda Hospital (Milan, Italy) who received the vaccine from December 27, 2020 to February 28, 2021 were included.

RESULTS

In total, 4,088 HCWs received the first dose of the vaccine and 4,043 completed the vaccination cycle. After the first injection, 1.6% of HCWs requested sick leave, while after the second injection, the number of requests significantly increased (+6.1%, p<0.001). A significant increase in sick leave was detected for those who have had SARS-CoV-2 infection after the first injection (+2.3%, p<0.001). After the second dose, a significant increase in sick leave was observed in the 20-30-year-old group compared to >30 years (+3.6%, p=0.017), if HCWs without a history of SARS-CoV-2 infection were considered.

CONCLUSIONS

The requests for sick leave among HCWs following the anti-COVID-19 vaccine were limited and higher after the second injection. This may help the management of the human resources when the large-scale administration of the anti-COVID-19 vaccines will involve other categories of workers.

Real-world corticosteroid use in severe pneumonia: a propensity-score-matched study

BACKGROUND

Community-acquired pneumonia (CAP) is a leading cause of morbidity and mortality worldwide despite correct antibiotic use. Corticosteroids have long been evaluated as a treatment option, but heterogeneous effects on survival have precluded their widespread implementation. We aimed to evaluate whether corticosteroids might improve clinical outcomes in patients with severe CAP and high inflammatory responses.

STUDY DESIGN AND METHODS

We analyzed two prospective observational cohorts of patients with CAP in Barcelona and Rome who were admitted to intensive care with a high inflammatory response. Propensity score (PS) matching was used to obtain balance among the baseline variables in both groups, and we excluded patients with viral pneumonia or who received hydrocortisone.

RESULTS

Of the 610 patients admitted with severe CAP, 198 (32%) received corticosteroids and 387 had major criteria for severe CAP. All patients had a baseline serum C-reactive protein above 15 mg/dL. Patients who received corticosteroids were more commonly male, had more comorbidities (e.g., cancer or chronic obstructive pulmonary disease), and presented with significantly higher sequential organ failure assessment scores. Eighty-nine patients met major severity criteria (invasive mechanical ventilation and/or septic shock) and were matched per group. Twenty-eight-day mortality was lower among patients receiving corticosteroids (16 patients, 18%) than among those not receiving them (28 patients, 31%; p = 0.037). After PS matching, corticosteroid therapy reduced the 28-day mortality risk in patients who met major severity criteria (hazard ratio (HR) 0.53, 95% confidence interval (CI) 0.29-0.98) (p = 0.043). In patients who did not meet major severity criteria, no benefits were observed with corticosteroid use (HR 0.88 (95%CI 0.32-2.36).

CONCLUSIONS

Corticosteroid treatment may be of benefit for patients with CAP who have septic shock and/or a high inflammatory response and requirement for invasive mechanical ventilation. Corticosteroids appear to have no impact on mortality when these features are not present.

Clinical Parasitology and Parasitome Maps as Old and New Tools to Improve Clinical Microbiomics

A growing body of evidence shows that dysbiotic gut microbiota may correlate with a wide range of disorders; hence, the clinical use of microbiota maps and fecal microbiota transplantation (FMT) can be exploited in the clinic of some infectious diseases. Through direct or indirect ecological and functional competition, FMT may stimulate decolonization of pathogens or opportunistic pathogens, modulating immune response and colonic inflammation, and restoring intestinal homeostasis, which reduces host damage. Herein, we discuss how diagnostic parasitology may contribute to designing clinical metagenomic pipelines and FMT programs, especially in pediatric subjects. The consequences of more specialized diagnostics in the context of gut microbiota communities may improve the clinical parasitology and extend its applications to the prevention and treatment of several communicable and even noncommunicable disorders.

Prognosis after neoadjuvant chemoradiation or chemotherapy for locally advanced gastro-oesophageal junctional adenocarcinoma

BACKGROUND

Trials typically group cancers of the gastro-oesophageal junction (GOJ) with oesophageal or gastric cancer when studying neoadjuvant chemoradiation and perioperative chemotherapy, so the results may not be fully applicable to GOJ cancer. Because optimal neoadjuvant treatment for GOJ cancer remains controversial, outcomes with neoadjuvant chemoradiation versus chemotherapy for locally advanced GOJ adenocarcinoma were compared retrospectively.

METHODS

Data were collected from all patients who underwent neoadjuvant treatment followed by surgery for adenocarcinoma located at the GOJ at a single high-volume institution between 2002 and 2017. Postoperative major complications and mortality were compared between groups using Fisher's exact test. Overall survival (OS) and disease-free survival (DFS) were assessed by log rank test and multivariable Cox regression analyses. Cumulative incidence functions were used to estimate recurrence, and groups were compared using Gray's test.

RESULTS

Of 775 patients, 650 had neoadjuvant chemoradiation and 125 had chemotherapy. These groups were comparable in terms of clinical tumour and lymph node categories, although the chemoradiation group had greater proportions of white men, complete pathological response to chemotherapy, and smaller proportions of diffuse cancer, poor differentiation, and neurovascular invasion. Postoperative major complications (20.0 versus 17.6 per cent) and 30-day mortality (1.7 versus 1.6 per cent) were not significantly different between the chemoradiation and chemotherapy groups. After adjustment, type of therapy (chemoradiation versus chemotherapy) was not significantly associated with OS (hazard ratio (HR) 1.26, 95 per cent c.i. 0.96 to 1.67) or DFS (HR 1.27, 0.98 to 1.64). Type of recurrence (local, regional, or distant) did not differ after neoadjuvant chemoradiation versus chemotherapy.

CONCLUSION

In patients undergoing surgical resection for locally advanced adenocarcinoma of the GOJ, OS and DFS did not differ significantly between patients who had neoadjuvant chemoradiation compared with chemotherapy.

Long term outcomes of canal wall up and canal wall down tympanomastoidectomies in pediatric cholesteatoma

Cholesteatomas in children have a more aggressive growth pattern compared to adults, which leads to a higher incidence of both residual and recurrent disease. A staged canal wall-up or a canal wall-down tympanomastoidectomy (CWUT and CWDT, respectively) is selected depending on the extent of the disease and condition of the middle ear (ME) cleft and mastoid. Endoscopic ear surgery (EES) has been recently introduced as an adjuvant tool for the treatment of this pathology even in the pediatric population.

OBJECTIVES

To analyze long term outcomes of CWUT and CWDT in the pediatric population, focusing on residual and recurrence rates of cholesteatoma and hearing results. A literature review including cases treated with EES were discussed.

MATERIAL AND METHODS

Pediatric patients treated for cholesteatoma involving both the ME and mastoid with a follow-up (FU) of at least 4 years were retrospectively analyzed in a quaternary referral center for otology and lateral skull base surgery. Patients were grouped according to the surgical technique (CWUT versus CWDT). Rates of residual and recurrent cholesteatoma after each surgical technique were reported and compared. Mean Air-Bone Gap (ABG) of 0.5-1-2-4 KHz was measured and reported before the first surgery and at the last post-operative FU.

RESULTS

Two-hundred and thirty-six cases fulfilled our inclusion criteria. The mean FU was 100.4 ± 44.2 months (median 89 months). One-hundred and five (44.5%) cases underwent a CWUT, whereas 131 (55.5%) a CWDT. A second stage surgery was performed in 73.5% of CWUT and 58.7% of CWDT. Among the CWUT group, residual cholesteatoma occurred in 22 (21%) ears and recurrence in 24 (22.9%). Patients undergoing CWDT showed lower rates of both residual and recurrent cholesteatoma (7.6% and 2.3%, respectively). ABG improvement was noted for both groups, even though CWUT showed better post-operative hearing results.

CONCLUSIONS

The CWDT technique offers a definite surgical therapy, with minimal residual and recurrence rates and audiological results comparable to the CWUT technique. EES must still prove its added benefit or equivalence to pure microscopic approaches.

Spinal hematoma after total knee arthroplasty: a case report

Spinal anesthesia is a common procedure performed in orthopedic surgery, and it is regarded as secure and safe. Although puncture-related complication of spinal anesthesia has a very low incidence, it would lead to dramatic neurological damage (tetra- or paraplegia). Early diagnosis and surgical decompression are mandatory to promote a better outcome. We present a case of acute spinal hematoma from T11 to L3, triggered by laborious anesthesia puncture after total knee arthroplasty. A prompt surgical decompression within few hours after diagnosis allowed rapid functional recovery and avoided permanent paraplegia.