Electrophoretic characterization of soluble protein extracts of Legionella pneumophila and other members of the family Legionellaceae.

The soluble peptides of strains of Legionella pneumophila, Tatlockia micdadei, Fluoribacter bozemanae, Fluoribacter dumoffii, and Fluoribacter gormanii were studied by polyacrylamide gel electrophoresis. Characteristic patterns were seen for Legionella and Tatlockia strains, whereas the patterns for the Fluoribacter strains were variable as would be expected for this genetically heterogeneous group. Grouping by peptide pattern was consistent with proposed taxons based on DNA-DNA homology. By using a new silver stain technique, the sensitivity and ease of pattern recognition were enhanced significantly. This technique is an easily applied general method for distinguishing between strains in epidemiological studies.     

Osteosarcomatosis

A review of the 690 cases of osteosarcoma in the radiographic file of the Armed Forces Institute of Pathology revealed 29 cases of "osteosarcomatosis" (multiple skeletal sites of osteosarcoma). Fifteen of these patients were 18 years old and under and manifested rapidly appearing, usually symmetric, sclerotic metaphyseal lesions. The remaining 14 patients were more than 18 years old and had fewer, asymmetric sclerotic lesions. In most patients (28 of 29), a radiographically dominant skeletal tumor was seen. Pulmonary metastases occurred in the majority of patients and were detected at the same time as the bone lesions. These 29 patients were studied with regard to demographic data and skeletal distribution and radiographic appearance of their lesions. As a result of the findings, a metastatic origin from a primary dominant osteosarcoma is favored over a multifocal origin as the basis for osteosarcomatosis. Osteosarcomatosis is more commonly encountered in the mature skeleton than has been previously recognized.     

Oxytocin mobilizes calcium from a unique heparin-sensitive and thapsigargin-sensitive store in single myometrial cells from pregnant rats

Intracellular free Ca²⁺ concentration ([Ca²⁺]_i) was monitored using the fluorescence from the dye Fura-2-AM in single myometrial cells from pregnant rats. Oxytocin and acetylcholine applied to the cell evoked an initial peak in [Ca²⁺]_i followed by a smaller sustained rise which was rapidly terminated upon removal of acetylcholine or persisted after oxytocin removal. A Ca²⁺ channel blocker (oxodipine) and external Ca²⁺ removal decreased both the transient and sustained rises in [Ca²⁺]_i suggesting that Ca²⁺ influx through L-type Ca²⁺ channels participated in the global Ca²⁺ response induced by oxytocin. However, the initial peak in [Ca²⁺]_i produced by oxytocin was mainly due to Ca²⁺ store release: it was abolished by inclusion of heparin [which blocks inositol 1,4,5-trisphosphate (InsP ₃) receptors] in the pipette (whole-cell recording mode of patch-clamp) and external application of thapsigargin (which blocks sarcoplasmic reticulum Ca²⁺-ATPases). In contrast, the transient Ca²⁺ response induced by oxytocin was unaffected by ryanodine. Moreover, caffeine failed to induce a rise in [Ca²⁺]_i but reduced the oxytocin-induced transient Ca²⁺ response. The later sustained rise in [Ca²⁺]_i produced by oxytocin was due to the entry of Ca²⁺ into the cell as it was suppressed in external Ca²⁺-free solution. The Ca²⁺ entry pathway is permeable to Mn²⁺ ions, in contrast to that described in various vascular and visceral smooth muscle cells. Oxytocin-induced Ca²⁺ release is blocked by the oxytocin antagonist d(CH₂)₅[Tyr(Me)²,Thr⁴,Tyr-NH ₂ ⁹ ]OVT. The prolonged increase in [Ca²⁺]_i after oxytocin removal is rapidly terminated by addition of the oxytocin antagonist suggesting that oxytocin dissociation from its receptor is very slow. The oxytocin stimulation of [Ca²⁺]_i was insensitive to incubation with pertussis toxin, and blocked by a pipette solution containing anti-q/₁₁ antibody. These data show that myometrial cells possess an unique heparin-sensitive and thapsigargin-sensitive store that can be mobilized by activation of oxytocin receptors which couples with a Gq/G₁₁-protein to activate phospholipase C.     

Air pollution and respiratory drug sales in the City of Le Havre, France, 1993-1996

The aim of this study is to evaluate ambulatory respiratory drug sales data as health indicators for the short-term effects of ambient air pollution in the city of Le Havre. Daily respiratory drug sales data were crossed with daily ambient air concentrations of sulfur dioxide (SO2), nitrogen dioxide (NO2), and black smoke (BS) using an autoregressive Poisson regression model adjusting for time trends, seasonal variations, influenza epidemics, and weather. Relative risks (RR) were expressed for an increase of two standard deviations above the mean of each pollutant. Respiratory drug sales were associated with most pollutants studied with lags varying from 1 to 9 days. For daily mean concentrations of BS, RR = 1.037 (95% confidence interval (CI) 1.009-1.066) for lag 1 and RR = 1.052 (95% CI 1.023-1.081) for lag 8. For daily mean concentrations of N02, RR = 1.033 (95% CI 1.001-1.066) for lag 1 and RR = 1.046 (95% CI 1.014-1.079) for lag 8. RR observed with a daily 1 h maximum of SO2 were RR= 1.027 (95% CI 1.004-1.051) for lag 3 and RR= 1.032 (95% CI 1.009-1.056) for lag 9. Our study concludes that ambulatory respiratory drug sales data could be useful for epidemiological surveillance of air pollutant health effects.     

Unsuspected idiopathic mediastinal fibrosis complicating coronary bypass operation

A 66-year-old woman was referred for coronary bypass operation to the left anterior descending and the circumflex arteries. She had a systemic inflammatory process of unknown origin. On opening the pericardium, fibrotic plaques encircling the entire ascending aorta were found. Aortic cannulation and proximal anastomosis of the planned vein graft were impossible. The right internal mammary was anastomosed to the left anterior descending artery, the left to the obtuse marginal after femoral arterial cannulation. Pathologic examination revealed idiopathic mediastinal fibrosis.     

Less invasive surgical treatment of renal cell carcinomas extending into the right heart and pulmonary arteries: surgery for renal cell carcinoma

BACKGROUND: Radical resection using deep hypothermic circulatory arrest improves the survival of patients with transvenous intracardiac tumor extension of renal cell carcinomas. A less invasive surgical approach avoiding deep hypothermia, circulatory arrest, and cross-clamping of the aorta is presented. METHODS: Between 1987 and 1999, 12 patients (mean age 57+/-8 years) underwent resection of a renal cell carcinoma extending into the right atrium, right ventricle, or pulmonary arteries. After median sterno-laparotomy, normothermic cardiopulmonary bypass is used cannulating the ascending aorta, superior caval vein, and inferior caval vein below the renal veins. The tumor and the corresponding kidney are radically excised, including the renal vein. Tumor fragments from the inferior caval vein, the right heart, and pulmonary arteries are removed either on the fibrillating or beating heart. RESULTS: Operative mortality was 0%. Mean cardiopulmonary bypass time was 53+/-27 minutes (median 36; range 32-110 minutes). Mean blood loss per patient was 1200 mL. Mean duration of postoperative mechanical ventilation was 36+/-12 hours (median 36; range 30-77 hours), mean intensive care stay 5.5+/-5 days (median 3; range 1-48 days), and mean duration of hospitalization 22+/-12 days (median 21; range 10-58 days). All patients were discharged home. Patients with multiple tumor manifestations outside the cardiovascular systems died within 9 months after the operation. CONCLUSIONS: The use of normothermic cardiopulmonary bypass is a less invasive method for radical resection of renal cell carcinoma with intracardiac tumor extension. Radical resection does not improve survival in patients with multiple distant metastases.     

Effect of the new imidazoline derivative S-22068 (PMS 847) on insulin secretion in vitro and glucose turnover in vivo in rats.

We have investigated the possible mechanisms underlying the antihyperglycaemic effect of the imidazoline derivative S-22068. In vitro, in the presence of 5 mmol/l glucose, S-22068 (100 micromol/l) induced a significant and sustained increase in insulin secretion from isolated, perifused, rat islets and a marked sensitization to a subsequent glucose challenge (10 mmol/l). S-22068 (100 micromol/l was able to antagonize the stimulatory effect of diazoxide on 86Rb efflux from preloaded islets incubated in the presence of 20 mmol/l glucose. Experiments were also performed to investigate whether S-22068 can alter glucose turnover and peripheral insulin sensitivity in vivo in mildly diabetic rats and obese, insulin resistant, Zucker rats. Neither glucose production nor individual tissue glucose utilization was modified by S-22068 in either group of rats. Similar results were obtained whether the studies were performed under basal conditions or during euglycaemic/hyperinsulinemic clamps. The results suggest that S-22068 exerts part of its antihyperglycaemic effect by promoting insulin secretion without alteration of peripheral insulin sensitivity.