An ultrasensitive Cystatin C renal failure immunosensor based on a PPy/CNT electrochemical capacitor grafted on interdigitated electrode.

An interdigitated immunosensor for Cystatin C detection based on polypyrrole/carbon nanotube electrochemical capacitor is described. Cystatin C (CysC) is powerful biomarker for early acute renal failure and one predictive for cardiovascular risk, sepsis, cancer and death. Recently, electrochemical immunosensors based on interdigitated electrodes (IDE) have been successfully focused on development of point-of-care testing, due to their miniaturization facilities and higher sensitivity as compared with the screen-printed electrochemical sensing. Herein, a polypyrrole/carbon nanotube nanoyhibrid film was grafted on two gold fingers by electropolymerization obtaining a supercapacitor. Anti-CysC antibodies were immobilized on the IDE by covalent entrapment via ethylenediamine bifunctional agent, followed by glycine blocking in acid and alkaline medium. Under low frequency, capacitive effect of antigen-antibody interaction were observed by double layer capacitance, and analytical responses of this IDE immunosensor to CysC serum were obtained by changes on phase angle a linear range up to 300 ng/mL. The cutoff was calculated for serum samples showing a total reducing of non-specific binding at approximately 28 ng/mL CysC. This immunosensor based on interdigitated electrode (IDE) is a potential tools as portable device,with possibility to use as a practical and rapid test for CysC diagnostic in samples of serum.

Effects of Organizational Characteristics on Outcomes and Resource Use in Patients With Cancer Admitted to Intensive Care Units.

PURPOSE: To investigate the impact of organizational characteristics and processes of care on hospital mortality and resource use in patients with cancer admitted to intensive care units (ICUs). PATIENTS AND METHODS: We performed a retrospective cohort study of 9,946 patients with cancer (solid, n = 8,956; hematologic, n = 990) admitted to 70 ICUs (51 located in general hospitals and 19 in cancer centers) during 2013. We retrieved patients' clinical and outcome data from an electronic ICU quality registry. We surveyed ICUs regarding structure, organization, staffing patterns, and processes of care. We used mixed multivariable logistic regression analysis to identify characteristics associated with hospital mortality and efficient resource use in the ICU. RESULTS: Median number of patients with cancer per center was 110 (interquartile range, 58 to 154), corresponding to 17.9% of all ICU admissions. ICU and hospital mortality rates were 15.9% and 25.4%, respectively. After adjusting for relevant patient characteristics, presence of clinical pharmacists in the ICU (odds ratio [OR], 0.67; 95% CI, 0.49 to 0.90), number of protocols (OR, 0.92; 95% CI, 0.87 to 0.98), and daily meetings between oncologists and intensivists for care planning (OR, 0.69; 95% CI, 0.52 to 0.91) were associated with lower mortality. Implementation of protocols (OR, 1.52; 95% CI, 1.11 to 2.07) and meetings between oncologists and intensivists (OR, 4.70; 95% CI, 1.15 to 19.22) were also independently associated with more efficient resource use. Neither admission to ICUs in cancer centers compared with general hospitals nor annual case volume had an impact on mortality or resource use. CONCLUSION: Organizational aspects, namely the implementation of protocols and presence of clinical pharmacists in the ICU, and close collaboration between oncologists and ICU teams are targets to improve mortality and resource use in critically ill patients with cancer.

Outcomes for patients with cancer admitted to the ICU requiring ventilatory support: results from a prospective multicenter study.

BACKGROUND: This study was undertaken to evaluate the clinical characteristics and outcomes of patients with cancer requiring nonpalliative ventilatory support. METHODS: This was a secondary analysis of a prospective cohort study conducted in 28 Brazilian ICUs evaluating adult patients with cancer requiring invasive mechanical ventilation (MV) or noninvasive ventilation (NIV) during the first 48 h of their ICU stay. We used logistic regression to identify the variables associated with hospital mortality. RESULTS: Of 717 patients, 263 (37%) (solid tumors = 227; hematologic malignancies = 36) received ventilatory support. NIV was initially used in 85 patients (32%), and 178 (68%) received MV. Additionally, NIV followed by MV occurred in 45 patients (53%). Hospital mortality rates were 67% in all patients, 40% in patients receiving NIV only, 69% when NIV was followed by MV, and 73% in patients receiving MV only (P < .001). Adjusting for the type of admission, newly diagnosed malignancy (OR, 3.59; 95% CI, 1.28-10.10), recurrent or progressive malignancy (OR, 3.67; 95% CI, 1.25-10.81), tumoral airway involvement (OR, 4.04; 95% CI, 1.30-12.56), performance status (PS) 2 to 4 (OR, 2.39; 95% CI, 1.24-4.59), NIV followed by MV (OR, 3.00; 95% CI, 1.09-8.18), MV as initial ventilatory strategy (OR, 3.53; 95% CI, 1.45-8.60), and Sequential Organ Failure Assessment score (each point except the respiratory domain) (OR, 1.15; 95% CI, 1.03-1.29) were associated with hospital mortality. Hospital survival in patients with good PS and nonprogressive malignancy and without tumoral airway involvement was 53%. Conversely, patients with poor functional capacity and cancer progression had unfavorable outcomes. CONCLUSIONS: Patients with cancer with good PS and nonprogressive disease requiring ventilatory support should receive full intensive care, because one-half of these patients survive. On the other hand, provision of palliative care should be considered the main goal for patients with poor PS and progressive underlying malignancy.

A flow-injection biamperometric method for determination of pantoprazole in pharmaceutical tablets.

A flow-injection biamperometric method for determination of pantoprazole (PTZ) in pharmaceutical tablets is reported for the first time. The reversible redox couples Fe3+/Fe2+, Fe(CN)6(3-)/Fe(CN)6(4-), Ce4+/Ce3+, VO3(-)NO2+, and I2/I- were tested as indicating redox systems for biamperometric determination of PTZ in a flow-injection assembly with optimized flow parameters. The best results were obtained using V03(-)NO2+, which showed to be a selective and sensitive biamperometric indicating system for PTZ even in the presence of excipients and antioxidants that typically are found in drugs. The analytical graph was linear (r = 0.99945) in the range from 10 to 100 mg/L using 25 mmol/L VO3(-) as the reagent and water as the carrier stream and applying 100 mV between the 2 platinum wire electrodes. The limits of detection and quantitation were 200 and 667 microg/L, respectively, with a sensibility of calibration of 22.6 mV/mg/L. The proposed method was successfully applied to determine PTZ in commercial pharmaceutical tablets with a mean relative error of 1.60% (n = 5) and mean relative standard deviation of 3.10%. Recoveries close to 100% showed good agreement between the expected amount of PTZ in tablets (40 mg) and the results found by the application of the proposed method and demonstrated that the formulations used in the tablet compositions do not interfere in the PTZ analysis. The system had good stability, with a relative standard deviation of 3.80% for 9 sequential injections of a 60 mg/L PTZ solution. A sampling rate of about 100 samples/h was obtained.