Possible relevance of pigeons as an indicator species for monitoring air pollution.

Wild city pigeons were caught at four different locations in the Netherlands to represent areas of high (Amsterdam-high), moderate (Amsterdam-medium), and low (Maastricht and Assen) traffic density. It is assumed that local ambient air pollution decreases as a function of traffic density. In these pigeons levels of polycyclic aromatic hydrocarbon (PAH)-DNA adducts, oxidative DNA damage, and heavy metal residues were determined in kidney, lung, liver, and blood (no adduct analysis in blood). The contribution of leaded gasoline to total body lead content was estimated by measuring concentrations of Pb and its isotopes in blood. We also analyzed samples of ambient air particulate matter for PAH and heavy metal concentrations at the four different locations. Interregional differences in heavy metals in ambient air particulate matter were reflected relatively well by pigeon body loads. The higher lead and cadmium concentrations in blood, kidney, liver, and lung were found in the Amsterdam high traffic density area, followed by Amsterdam medium, Assen, and Maastricht. A high Pb concentration in blood coincided with relatively low 206Pb/207Pb values, indicating a high contribution of leaded gasoline to total blood Pb concentrations in pigeons from the Amsterdam high traffic density area. Significantly enhanced blood zinc values were found in pigeons from both locations in Amsterdam compared to pigeons from the other two areas. However, no differences in Zn tissue levels between the four different groups were found. Oxidative DNA damage, determined as the ratio of 7-Hydro-8-oxo-2'-deoxyguanosine/ deoxyguanosine, in pigeon liver was highest in Amsterdam-high, followed by Assen (low traffic density). Pb content, but not the Cd content, was positively associated with oxidative DNA damage in liver tissue. In lung tissue, a negative correlation was found between oxidative DNA damage and Zn content. These results indicate that the carcinogenic potential of Pb might be ascribed to oxygen radical formation, whereas Zn plays a protective role against oxidative DNA damage. Places with high and medium traffic density could be clearly discriminated on the basis of PAH levels in the ambient air. The PAH content in particulate air samples was not, however, reflected in total PAH-related DNA adduct levels because no differences could be observed in tissue adduct levels in pigeons from the four different locations. Our results indicate that wild city pigeons can be used as biological indicators of exposure to heavy metal pollution in outdoor air.     

Tolerance for light and sound of patients with persistent post-concussional symptoms 6 months after mild head injury

Summary Patients with post-concussional symptoms (PCS) about 6 months after a mild head injury (MHI) were examined for tolerance of light and sound in comparison with concussed patients without PCS and nonconcussed healthy controls. MHI patients with PCS were individually matched with subjects from the two control groups for the time elapsed from the injury, and for age and sex. Using a computerized rating technique, we assessed both the maximal and submaximal levels of lowered tolerance for light and sound over a wide range of stimuli. We found that the MHI patients with PCS 6 months after the trauma (n=11) tolerated significantly less well stimuli of intensities of 71 dB and 500 lx than MHI patients without PCS (n=11) and non-concussed controls (n=11). There were no significant differences in tolerance for light and sound between MHI patients without PCS and the non-injured controls. Decreased tolerance for light and sound may contribute to the persistence of symptoms up to 6 months after a mild head injury. The psychophysical method provides an objective measure for the evaluation of the late persistent postconcussional syndrome.     

Shoulder instability: impact of glenohumeral arthrotomography on treatment

We used arthrotomography to study the glenoid labrum in 114 patients. Sixty-nine of the patients had anatomic instability of the shoulder (including recurrent dislocation and subluxation of the shoulder), and 45 patients had functional instability of the shoulder (denoted by chronic pain, clicking of the joint, and the sensation that an unstable condition exists without the objective signs of it). Labral tears were revealed arthrotomographically in 86% of the patients with anatomic instability, while only 40% of the patients with functional instability had labral abnormalities, and these were primarily of minor severity. Fifty-six patients (44 of whom had anatomic instability; 12, functional instability) required surgery. The surgical findings were correlated with the arthrotomographic findings, and no false-positive results were revealed. However, arthrotomography demonstrated only part of the pathologic condition of two patients. These results confirm that there is a strong correlation between labral pathologic conditions and anatomic instability of the shoulder. Arthrotomographic studies have a great impact on the selection of therapy in cases of both anatomic and functional instability of the shoulder.     

Rupture of the posterior tibial tendon: CT and surgical findings

Computed tomography (CT) was performed in 42 patients with 49 clinically suspected tears of the posterior tibial tendon. Twenty-eight of the 49 suspected tears were subsequently surgically explored and repaired. Three patterns of tendon abnormalities were recognized on CT scans: type I-intact, hypertrophied, heterogeneous tendon; type II-attenuated tendon; and type III-absence of a portion of a tendon. Types I and II correlated with partial rupture seen during surgery, and type III correlated with complete rupture of the tendon. CT findings were accurate in 96% of the patients who underwent surgery. In four cases (14%), tendon rupture was seen on CT scans, but the extent of the injury was underestimated and the rupture was misclassified. Reactive periostitis of the distal tibia was seen in 71% of diseased tendons and may represent an important factor in the diagnosis of tendon rupture.     

Toxicology of FK506 in the cynomolgus monkey: a clinical,biochemical, and histopathological study

We investigated clinical, biochemical, and histopathological parameters in FK506-treated cynomolgus monkeys. Eight monkeys given oral FK506, 1 (n = 4) or 10 (n = 4) mg/kg daily, survived the 90 days of treatment apparently in good health and without significant changes in biochemical and histopathological parameters, as did 2 control monkeys except one monkey on 10 mg/kg/day FK506 orally, who was found to have a malignant lymphoma. In contrast, monkeys given intramuscular FK506 1 mg/kg daily (n = 4) had to be sacrificed at day 20, 25, 32, and 47 because of severe illness. They showed abnormal biochemical parameters (increased serum urea and aspartate aminotransferase activity) and major histopathological changes in the kidney (mesangial cell proliferation and acute tubular necrosis), pancreas (depletion of beta cells), liver (steatosis), and heart (cardiomyopathy). Intramuscular administration of 1 mg/kg daily resulted in serum levels ranging from 10 to 15 ng/ml, while oral administration at a dose of 1 or 10 mg/kg daily resulted in equal or even higher serum levels (range 2–70 ng/ml). Thus, the height of the serum trough level of FK506 using the enzyme immunoassay is not related to the toxicity of FK506 in cynomolgus monkeys.