Lab-on-a-Drone: remote voltammetric analysis of lead in water with real-time data transmission.

The present work describes a laboratory-on-a-drone (Lab-on-a-Drone) developed to perform in situ detection of contaminants in environmental water samples. Toward this goal, the system was mounted on an unmanned aerial vehicle (UAV) (drone) and remotely controlled via Wi-Fi to acquire a water sample, perform the electrochemical detection step, and then send the voltammetry data to a smartphone. This Lab-on-a-Drone system was also able to recharge its battery using a solar cell, greatly increasing the autonomy of the system, even in the absence of a power line. As a proof of concept, the Lab-on-a-Drone was employed for the detection of Pb2+ in environmental waters, using a simple electrochemical cell containing a miniaturized screen-printed boron-doped diamond electrode (SP-BDDE) as a working electrode, an Ag/AgCl as a reference electrode, and a graphite ink as a counter electrode. For quantification purposes, analytical curves were constructed covering a concentration range from 1.0 µg L-1 (4.83 nmol L-1) to 80.0 µg L-1 (386.10 nmol L-1), featuring a detection limit of 0.062 µg L-1 (0.30 nmol L-1). The Lab-on-a-Drone was applied to monitor a water reservoir in the Metropolitan Region of Recife, Brazil. To evaluate its performance regarding accuracy and precision, a reference method based on inductively coupled plasma optical emission spectrometry (ICP-OES) was applied, and the results obtained by both methods showed no statistical differences (t-test at 95% confidence level, n = 3). These results represent the first demonstration of the capabilities of an adapted UAV for the quantification of electroactive environmental contaminant using voltammetry, with real-time data transmission. Thus, the Lab-on-a-Drone makes it possible to reach difficult-to-access environmental reserves and to monitor potentially polluting activity in distant water bodies. Thus, this tool can be used by governments and non-profit organizations to monitor environmental waters using fast, low-cost, process autonomy with accurate and precise data useful to decision making.

Myosteatosis in a systemic inflammation-dependent manner predicts favorable survival outcomes in locally advanced esophageal cancer.

Increased adiposity and its attendant metabolic features as well as systemic inflammation have been associated with prognosis in locally advanced esophageal cancer (LAEC). However, whether myosteatosis and its combination with systemic inflammatory markers are associated with prognosis of esophageal cancer is unknown. Our study aimed to investigate the influence of myosteatosis and its association with systemic inflammation on progression-free survival (PFS) and overall survival (OS) in LAEC patients treated with definitive chemoradiotherapy (dCRT). We retrospectively gathered information on 123 patients with LAEC submitted to dCRT at the University of Campinas Hospital. Computed tomography (CT) images at the level of L3 were analyzed to assess muscularity and adiposity. Systemic inflammation was mainly measured by calculating the neutrophil-to-lymphocyte ratio (NLR). Median PFS for patients with myosteatosis (n = 72) was 11.0 months vs 4.0 months for patients without myosteatosis (n = 51) (hazard ratio [HR]: 0.53; 95% confidence interval [CI], 0.34-0.83; P = .005). Myosteatosis was also independently associated with a favorable OS. Systemic inflammation (NLR > 2.8) was associated with a worse prognosis. The combination of myosteatosis with systemic inflammation revealed that the subgroup of patients with myosteatosis and without inflammation presented less than half the risk of disease progression (HR: 0.47; 95% CI: 0.26-0.85; P = .013) and death (HR: 0.39; 95% CI, 0.21-0.72; P = .003) compared with patients with inflammation. This study demonstrated that myosteatosis without systemic inflammation was independently associated with favorable PFS and OS in LAEC patients treated with dCRT.

Chagasic Megaesophagus-Associated Carcinoma: Clinical Pattern and Outcomes.

PURPOSE: Approximately 4% to 10% of patients diagnosed with Chagas-induced megaesophagus disease develop esophageal carcinoma. However, the natural history and clinical pattern of this entity are not well described. METHODS: Herein, we retrospectively analyzed 593 patients with esophageal carcinoma treated at a single Brazilian institution. We identified 32 patients with Chagas disease, of whom 11 had megaesophagus. The epidemiologic profile and oncological treatment outcomes were evaluated. RESULTS: Although baseline characteristics were similar among the three groups, patients with Chagas megaesophagus-associated carcinoma (CMAC) presented with a lower rate of smoking. This factor reinforced the concept that achalasia is the predominant risk factor for cancer development. The CMAC group had a higher rate of tumor in situ (two of 11 patients) compared with the other groups. These patients were treated with endoscopic resection, and no recurrence was detected. Eight of 11 patients with CMAC were diagnosed with locally advanced disease. Patients with locally advanced CMAC presented with a median progression-free survival of 7.8 months and a median overall survival of 9.1 months. CONCLUSION: If CMAC is not promptly detected, it has a dismal prognosis, indicating that a high index of suspicion of esophageal carcinoma is required for patients with Chagasic megaesophagus. Additional studies are needed to improve the surveillance and treatment approaches for this neglected disease.