Potential Phytoplankton Productivity of Three Iowa Streams

A series of experiments were conducted to test the hypothesis that the concentrations of suspended algal populations in central Iowa streams are not limited by nutrient concentrations. River water samples with their natural plankton populations were collected from the Des Moines River, Skunk River, and Squaw Creek and were cultured under controlled conditions without the addition of nutrients. In 23 of 24 experiments significant increases in algal chlorophyll a were found with an average replication factor of 14 times. The data indicate that nutrients are not limiting suspended algal densities in the streams. A second series of experiments indicated that nitrate concentrations of up to 20 mg/I nitrate-nitrogen did not inhibit algal growth in these river waters

Multi-detector row computed tomography (MDCT) and magnetic resonance imaging (MRI) in the evaluation of the mandibular invasion by squamous cell carcinomas (SCC) of the oral cavity. Correlation with pathological data

<p>Abstract</p> <p>Background</p> <p>To retrospectively compare the diagnostic accuracy of magnetic resonance imaging (MRI) and multidetector-row computed tomography (MDCT) in the assessment of the mandibular invasion by squamous cell carcinoma (SCC) having histopathological exams as standard of reference.</p> <p>Materials and methods</p> <p>Institutional review board approval with a waiver of informed patient consent was obtained. Of the 147 patients selected from our database who underwent surgical excision of a tumour arising into the oral cavity, thirty-six patients (26 men, 10 women; mean age, 56 years; range, 30-75 years) with hystologically proven SCC who performed both a preoperative MRI and MDCT, composed our final study population.</p> <p>Images were qualitatively analyzed in consensus by two expert radiologist in head and neck imaging. Sensitivity, specificity, accuracy, positive predictive value (PPV) and negative predictive value (NPV) were assessed for both MRI and MDCT.</p> <p>Differences in sensitivity, specificity, positive and negative predictive values were calculated at a statistical significance of p < .05.</p> <p>Results</p> <p>The sensitivity, the specificity and the accuracy of MRI and MDCT in the detection of the mandibular involvement were respectively 93%, 82%, 86% and 79%, 82%, 81%, while the positive predictive value (PPV) and negative predictive value (NPV) were respectively 76%, 95% and 73%, 86%. There wasn't any statistically significant difference in overall diagnostic accuracy between MRI and MDCT in the evaluation of mandibular tumour invasion (p > .05).</p> <p>Conclusion</p> <p>MRI showed to have a higher sensitivity compare to MDCT in the assessment of mandibular involvement from SCC arising in the oral cavity although none statistically significant differences were noted.</p

Correlation between tumor necrosis factor-alpha and D-dimer levels in non-small cell lung cancer patients

The present study was designed to investigate whether a correlation exists between IL-6, TNF-alpha and coagulation (Thrombin-antithrombin, TATc) or fibrinolysis (D-dimer) activation in non-small cell lung cancer (NSCLC) patients. One hundred thirty patients with NSCLC (n=65, 53 males, mean age 65 +/- 8, adenocarcinoma n=32, squamous cancer n=33) or chronic obstructive pulmonary disease (COPD) (n=65, 51 males, mean age 67 +/- 9) were studied. As control group 65 healthy donors (51 males, mean age 61 +/- 14) were also evaluated. The results obtained showed that median D-dimer levels were higher in NSCLC patients (3.0 microg/ml) compared either to COPD patients (1.1 microg/ml, P<0.05) or controls (0.3 microg/ml, P<0.0001). Positive TNF-alpha levels (>10 pg/ml) were found in 26% of NSCLC compared to 3% of COPD (P<0.002) and 5% of controls (P<0.0005). On the other hand, positive (>8.5 pg/ml) IL-6 levels were found in 53% of NSCLC and 21% of COPD patients, compared to 5% of control subjects (P<0.001). Median TATc levels were elevated in either NSCLC (6.9 microg/l) or COPD (5.7 microg/l) patients compared to controls (1.8 microg/l, P<0.0001). Elevated D-dimer levels were significantly associated to positive TNF-alpha levels in patients without distant metastasis (F=4.3, P<0.05). Moreover, TNF-alpha levels (P<0.01) were independently related to the presence of positive D-dimer levels in patients with non-metastatic NSCLC. These results suggest that increased levels of TNF-alpha might be responsible for an activation of fibrinolysis in patients with NSCLC