[Tubulocystic renal cell carcinoma with poorly differentiated foci]. / Carcinome rénal tubulokystique avec composante peu différenciée.

Tubulocystic renal cell carcinoma is a rare tumor with an indolent behavior in the majority of cases. In contrast, tubulocystic renal cell carcinoma with poorly differentiated foci has a bad prognosis with an aggressive and metastatic behavior. We present the case of a patient diagnosed with tubulocystic renal cell carcinoma with poorly differentiated foci.

Parting ways: parasite release in nature leads to sex-specific evolution of defence.

We evaluated the extent to which males and females evolve along similar or different trajectories in response to the same environmental shift. Specifically, we used replicate experimental introductions in nature to consider how release from a key parasite (Gyrodactylus) generates similar or different defence evolution in male vs. female guppies (Poecilia reticulata). After 4-8 generations of evolution, guppies were collected from the ancestral (parasite still present) and derived (parasite now absent) populations and bred for two generations in the laboratory to control for nongenetic effects. These F2 guppies were then individually infected with Gyrodactylus, and infection dynamics were monitored on each fish. We found that parasite release in nature led to sex-specific evolutionary responses: males did not show much evolution of resistance, whereas females showed the evolution of increased resistance. Given that male guppies in the ancestral population had greater resistance to Gyrodactylus than did females, evolution in the derived populations led to reduction of sexual dimorphism in resistance. We argue that previous selection for high resistance in males constrained (relative to females) further evolution of the trait. We advocate more experiments considering sex-specific evolutionary responses to environmental change.

Occupational asthma due to gas metal arc welding on mild steel.

Occupational asthma has been documented in electric arc welders exposed to manual metal arc welding on stainless steel. A subject is described who developed late and dual asthmatic reactions after occupational-type challenge exposure to gas metal arc welding on uncoated mild steel.

Low grade coal worker's pneumoconiosis. Comparison of CT and chest radiography.

We compared CT with chest radiography (CR) in the assessment of low grade coal worker's pneumoconiosis (CWP) in a population of 83 subjects. All subjects had a high-voltage p.a. CR, graded according to the ILO classification between 0/0 and 1/1, a conventional CT (CCT) using contiguous 1-cm-thick sections on the entire thorax and a set of 10 high-resolution CT (HRCT) images. CR and CT were separately read by consensus by 2 teams of 2 trained readers. CR was coded 0/0 in 9 subjects; 0/1 in 31; 1/0 in 28; 1/1 in 15. Among these groups of patients, micronodules were detected by CT in respectively 2 (22%), 14 (45%), 17 (61%) and 10 (67%) patients. In all groups, micronodules were more often detected by CT when the opacities detected on CR were scored as rounded (p, q) than irregular (s, t). Among the patients graded 0/0 or 0/1, CT showed micronodules in 40%. By contrast, among the patients graded 1/0 or 1/1, CT did not show micronodules in 37%, but revealed in numerous patients that opacities detected on CR were related to bronchiectasis and/or emphysema only. Comparative analysis of HRCT and CCT showed that both techniques are complementary and proved the usefulness of CCT in the detection or confirmation of low profusion of micronodules.

[Computed tomography of pneumoconioses]. / Tomodensitométrie des pneumoconioses.

Thoracic computed tomography is now used in the assessment of occupational diseases. Coal miner's pneumoconiosis, silicosis and benign asbestosis constitute the principal indications. The specific contribution of computed tomography techniques, their methodology and their signs are presented.

Neoplastic angioendotheliomatosis in a dog: an angiotropic lymphoma.

Neoplastic angioendotheliomatosis was diagnosed in a nine-year-old, intact male German Shorthaired Pointer exhibiting progressive neurological signs over a six-month period. At necropsy, there was multifocal asymmetric, hemorrhagic necrosis within the cerebral hemispheres, centrum semiovale, caudate nucleus, and internal capsule. Histologically, there was extensive intravascular proliferation of pleomorphic mononuclear cells within the brain and multiple parenchymatous organs. Transmission electron microscopy demonstrated the absence of intercellular junctions between neoplastic cells. These cells were not attached to the vascular lining endothelium; Weibel-Palade bodies and a basement membrane were lacking. By indirect immunofluorescence, positive cytoplasmic staining of intravascular neoplastic cells for IgG was demonstrated. Peroxidase-antiperoxidase technique for Factor VIII related antigen was negative. As in man, this rare neoplastic disorder appears to be a lymphoma, apparently of the B cell line.

Pulmonary extraction of serotonin and propranolol in patients with adult respiratory distress syndrome.

Because injury to the pulmonary vascular endothelium is associated with the development of the adult respiratory distress syndrome (ARDS), we assessed the metabolic function of pulmonary endothelial cells by the measurements of the first-pass pulmonary extraction of [14C]serotonin and [3H]propranolol in 15 patients with ARDS and 15 patients at risk for developing ARDS. Serotonin extraction ratio was lower in patients with ARDS (0.85 +/- 0.10, mean +/- SD) than in patients at risk (0.91 +/- 0.04) (p less than 0.025), and both values were significantly reduced (p less than 0.005) when compared with a control group value (0.97 +/- 0.01). The decrease in serotonin extraction was correlated with the severity of ARDS (r = -0.67) (p less than 0.001) and with pulmonary function changes over time. Propranolol extraction ratio was decreased in patients at risk (0.66 +/- 0.11) (p less than 0.005) but not in patients with ARDS (0.75 +/- 0.11), when compared with those in the control group (0.81 +/- 0.03). Low values in patients at risk were restored to normal by continuous positive airway pressure breathing. We conclude that pulmonary extraction of serotonin, an index of pulmonary endothelial cell function, correlates with the severity of ARDS.

Effects of atelectasis and vascular occlusion on the simultaneous measurement of serotonin and propranolol pulmonary extraction in dogs.

To test the relative sensitivity of serotonin and propranolol pulmonary extraction measurements to changes in pulmonary vascular surface, we sequentially subjected anaesthetized dogs to left upper lobe atelectasis, left lung atelectasis and left pulmonary artery occlusion. We used a triple-indicator dilution technique to simultaneously measure the pulmonary extraction of serotonin and propranolol. After an initial series of measurements, dogs received dopamine and dextran to slightly increase pulmonary artery pressure and prevent further recruitment of capillaries. Left upper lobe atelectasis did not modify the pulmonary extraction of serotonin and propranolol. Left lung atelectasis provoked a reduction in the serotonin extraction ratio by only 4%, whereas the propranolol extraction ratio decreased by 13%. After left pulmonary artery occlusion, propranolol and serotonin extraction ratios decreased by 16% and 5% respectively. We conclude that the pulmonary extraction of propranolol is more sensitive to a decrease in pulmonary vascular surface than that of serotonin.

Simultaneous measurement of serotonin and propranolol pulmonary extraction in patients after extracorporeal circulation and surgery.

To evaluate the use of markers of pulmonary endothelial cell function in humans, we simultaneously measured the pulmonary extraction of serotonin (SER) and propranolol (PROP) in patients before and after extracorporeal circulation (ECC) for coronary bypass surgery. No change was seen in SER extraction ratio after anesthesia, ECC, and surgery. Twenty-four hours after ECC and surgery, PROP extraction ratio was decreased by 11%. It remained low for as long as 5 days thereafter. A similar drop in PROP extraction was found in 6 patients 24 h after ilioaortic bypass surgery, without ECC (from 81 to 66%, p less than 0.01). Treatment of 11 other patients with a 30-min period of continuous positive airway pressure (CPAP), 24 to 48 h after ECC, resulted in a significant increase in PROP extraction ratio from 61 to 67% (p less than 0.01). Measurement of PROP extraction appears to be more sensitive than that of SER to lung changes related to postoperative atelectasis.