Likelihood of malignancy in a solitary pulmonary nodule: comparison of Bayesian analysis and results of FDG-PET scan

OBJECTIVE: To compare the probability of cancer in a solitary pulmonary nodule using standard criteria with Bayesian analysis and result of 2-[F-18] fluoro-2-deoxy-D-glucose-positron emission tomographic (FDG-PET) scan. SETTING: A university hospital and a teaching Veteran Affairs Medical Center. METHODS: Retrospective analysis of 52 patients who had undergone both CT scan of the chest and a FDG-PET scan for evaluation of a solitary pulmonary nodule. FDG-PET scan was classified as abnormal or normal. Utilizing Bayesian analysis, the probability of cancer using "standard criteria" available in the literature, based on patient's age, history of previous malignancy, smoking history, size and edge of nodule, and presence or absence of calcification were calculated and compared to the probability of cancer based on an abnormal or normal FDG-PET scan. Histologic study of the nodules was the gold standard. RESULTS: The likelihood ratios for malignancy in a solitary pulmonary nodule with an abnormal FDG-PET scan was 7.11 (95% confidence interval [CI], 6.36 to 7.96), suggesting a high probability for malignancy, and 0.06 (95% CI, 0.05 to 0.07) when the PET scan was normal, suggesting a high probability for benign nodule. FDG-PET scan as a single test alone was more accurate than the standard criteria and standard criteria plus PET scan in correctly classifying nodules as malignant or benign. CONCLUSION: FDG-PET scan as a single test was a better predictor of malignancy in solitary pulmonary nodules than the standard criteria using Bayesian analysis. FDG-PET scan can be a useful adjunct test in the evaluation of solitary pulmonary nodules.     

Normalizing Google Scholar data for use in research evaluation

Scientometrics - Using bibliometric data for the evaluation of the research of institutions and individuals is becoming increasingly common. Bibliometric evaluations across disciplines require that...     

Effect of Various Surfactants on the Viscosity,Thermal and Electrical Conductivity of Graphene Nanoplatelets Nanofluid

International Journal of Thermophysics - The paper describes the metrological characterization of the highly stable Pt-40%Rh/Pt-6%Rh thermocouples to determine their reference function in the...     

Attention-deficit hyperactivity symptomatology after traumatic brain injury: a prospective study

OBJECTIVE: To study prospectively the course of attention-deficit hyperactivity (ADH) symptomatology in children and adolescents after traumatic brain injury (TBI). It was hypothesized that ADH symptomatology would be significantly related to severity of injury. METHOD: Subjects were children (n = 50) aged 6 to 14 years at the time they were hospitalized after TBI. The study used a prospective follow-up design. Assessments of preinjury psychiatric, behavioral, socioeconomic, family functioning, and family psychiatric history status were conducted. Severity of injury was assessed by standard clinical scales, and neuroimaging was analyzed. RESULTS: The main finding of this study was that change in ADH symptomatology in the first 2 years after TBI in children and adolescents was significantly related to severity of injury. Overall ADH symptomatology during the study was significantly related to a measure of family dysfunction when family psychiatric history, socioeconomic status, and severity of injury were controlled. CONCLUSION: The presence of a positive "dose-response" relationship between severity of injury and change in ADH symptoms, present from the 3-month assessment, was consistent with an effect directly related to brain damage.     

Reliability of epidural pressure measurement in clinical practice: behavior of three modern sensors during simultaneous ipsilateral intraventricular or intraparenchymal pressure measurement

We studied 726 consenting patients to determine whether withholding oral fluids from adult ambulatory surgical patients before discharge would decrease the incidence of postoperative nausea and vomiting (PONV) and shorten the duration of stay in the ambulatory surgery unit (ASU). Patients were randomly assigned to the drinking or nondrinking group. Both groups received a standard regimen of general anesthesia, fluid replacement, and analgesia. In the ASU, patients in the drinking group were given mandatory oral fluids to drink before discharge. Nausea and pain were assessed by using a visual analog scale 15, 30, 60, 90, 105, 120, 150, and 180 min postoperatively. The time to drink, sit up, void, and ambulate, and the time until discharge were recorded. Patients were interviewed by telephone 24 h postoperatively. There was no significant difference in the frequency of PONV between the drinking and the nondrinking groups either in the hospital or after discharge. Patients in the drinking group required more time to begin ambulating (105 +/- 38 vs 98 +/- 34 min; P < 0.02) and to void (112 +/- 40 vs 105 +/- 37 min; P < 0.01). Patients in the drinking group also stayed in the ASU longer (85 +/- 49 vs 81 +/- 47 min; P < 0.03). Time to postanesthetic discharge was also significantly longer in the drinking group than the nondrinking group (106 +/- 40 vs 98 +/- 36 min; P < 0.015). A similar percentage of patients in both groups were "very satisfied" with their ambulatory surgical care. There was no difference in postoperative complications and need for medical help. Withholding early postoperative oral fluids facilitated earlier ambulation and decreased the stay in the ASU but did not decrease the incidence of PONV. Thus, in this ambulatory surgical population, there does not seem to be justification to require drinking before discharge. Implications: To answer the question of whether adult outpatients should drink before discharge after minor surgical procedures, 726 patients were randomized to either drink approximately 150 mL of liquid or not to drink. Neither drinking nor nondrinking worsened postoperative nausea or vomiting or prolonged hospital stay. Therefore, patients should be allowed to choose whether they drink before discharge.     

Polyurethane-poly(methyl methacrylate) interpenetrating polymer networks: Some mechanical properties

The mechanical behavior of polyurethane-poly(methyl methacrylate) interpenetrating polymer networks (PUR/PAc IPN's) was investigated. Stress-strain and impact resistance measurements were made on IPN's with a variable PUR content. The effect of the degree of crosslinking of each network on the mechanical properties was also studied. It appears that only the ultimate elongation varies largely upon changing the crosslink degree. The results are interpreted in terms of the contribution of each network to the mechanical behavior, but also by the interpenetration of both components and by the phase continuity of the PAc network.     

Detectors for polarized skylight in insects: a survey of ommatidial specializations in the dorsal rim area of the compound eye

Apart from the sun, the polarization pattern of the sky offers insects a reference for visual compass orientation. Using behavioral experiments, it has been shown in a few insect species (field crickets, honey bees, desert ants, and house flies) that the detection of the oscillation plane of polarized skylight is mediated exclusively by a group of specialized ommatidia situated at the dorsal rim of the compound eye (dorsal rim area). The dorsal rim ommatidia of these species share a number physiological properties that make them especially suitable for polarization vision: each ommatidium contains two sets of homochromatic, strongly polarization-sensitive photoreceptors with orthogonally-arranged analyzer orientations. The physiological specialization of the dorsal rim area goes along with characteristic changes in ommatidial structure, providing actual anatomical hallmarks of polarized skylight detection, that are readily detectable in histological sections of compound eyes. The presence of anatomically specialized dorsal rim ommatidia in many other insect species belonging to a wide range of different orders indicates that polarized skylight detection is a common visual function in insects. However, fine-structural disparities in the design of dorsal rim ommatidia of different insect groups indicate that polarization vision arose polyphyletically in the insects.