Linkage and redox isomerism in ruthenium complexes of catecholate, semi-quinone, and o-acylphenolate ligands derived from tri- and tetrahydroxy-9,10-anthracenediones.

The complexes Ru(CO)(2)L(2)(PHAQ-2H) (PHAQ = 1,2,4-trihydroxy-9,10-anthracenedione (PUR), 1,2,3- trihydroxy-9,10-anthracenedione (AG), and 1,2,5,8-tetrahydroxy-9,10-anthracenedione (QAL); L = PPh(3), PCy(3), PBu(3)), and Ru(CO)(dppe)(PBu(3))(PHAQ-2H), containing catecholate-type ligands were prepared. The complex Ru(CO)(2)(PBu(3))(2)(AG-2H) crystallizes in the space group P2(1)/n (No. 14 var) with a = 13.317(2), b = 15.628(2), c = 21.076(3) A, beta = 101.660(10) degrees, Z = 4; the crystal structure shows it to contain a 2,3-catecholate ligand. The electrochemistry of these complexes was examined, and the semi-quinone complexes [Ru(CO)(2)L(2)(PHAQ-2H)](1+) and [Ru(CO)(dppe)(PBu(3))(PHAQ-2H)](1+) were generated by chemical oxidation. One example of an o-acylphenolate complex, HRu(CO)(PCy(3))(2)(PUR-H), is also reported.

MR of esthesioneuroblastoma (olfactory neuroblastoma) and appearance after craniofacial resection.

PURPOSE: To analyze the MR characteristics of a series of patients with esthesioneuroblastoma and discuss the typical surgery and its postoperative MR appearance. METHODS: The MR studies of 15 patients with the pathologic diagnosis of esthesioneuroblastoma (also known as olfactory neuroblastoma) were retrospectively reviewed and correlated with CT and surgical findings. The postoperative MR studies of 10 patients who underwent craniofacial resection were also reviewed. RESULTS: In all cases the tumors arose in the superior nasal cavity and extended into the ethmoid cells. In some instances the tumors extended into the other paranasal sinuses, orbits, anterior cranial fossa, and cavernous sinus. The tumors were typically expansile and destructive in their growth patterns. Compared with brain gray matter, the tumors were hypointense on T1-weighted images and isointense to hyperintense on T2-weighted images. Nine tumors were heterogeneous and 6 were homogeneous. Contrast enhancement ranged from mild to marked. MR was useful for characterizing the various tissues and distinguishing fluid in the postoperative nasal cavity. CONCLUSIONS: Esthesioneuroblastoma, although an uncommon tumor, may be suspected in lesions of the superior nasal cavity demonstrating both expansile and destructive growth properties. The MR findings are otherwise nonspecific. MR is the imaging modality of choice for depicting local tumor extension and evaluating for recurrence after craniofacial resection.

Increased prevalence of cholelithiasis in patients with abdominal aortic aneurysm: sonographic evaluation.

We performed a prospective study to determine the prevalence of cholelithiasis in patients with abdominal aortic aneurysm. Over an 18-month period, the gallbladder and the abdominal aorta were evaluated routinely in all consecutive patients referred to us for sonography of the abdomen and retroperitoneum. The patients were divided into two groups: those with an abdominal aortic aneurysm (aorta greater than 3 cm in transverse diameter) (n = 96) and those whose aorta measured less than 3 cm in transverse diameter (n = 538), who served as control subjects. Cholelithiasis was found in 50% of patients with and 26% of patients without aneurysm (p less than .0001). A stepwise logistic regression analysis found age alone to be predictive of cholelithiasis (p = .030). However, age was not predictive of cholelithiasis when included with abdominal aortic aneurysm in a multivariate model. Diabetes mellitus and gender were not predictive of cholelithiasis. We found cholelithiasis in approximately half of the patients who had abdominal aortic aneurysms. This is almost double the prevalence in the general elderly population. A pathophysiologic explanation for this observation remains to be found.

Absence of bile acid malabsorption as a late effect of pelvic irradiation.

The pathophysiology of chronic radiation-induced diarrhea was evaluated in 28 patients who had undergone pelvic irradiation for gynecologic neoplasms 2 to 7 years previously. Twenty-seven patients undergoing radiotherapy with techniques that did not require abdominal or pelvic irradiation served as controls. The glycine conjugates of cholic acid (GC) were measured in serum by radioimmunoassay. Fasting and 2 hr. pp GC levels for the pelvic irradiated patients were 11.0 +/- 11.1 (mean +/- SD) and 24.8 +/- 17.3 micrograms/dl. Fasting and 2 hr. pp GC levels for controls were 12.6 +/- 7.4 and 28.0 +/- 14.7. There were no significant differences in the post-prandial increases in serum GC between pelvic irradiated patients and controls (p = .23, Type II error probability = .13). There was also no significant difference in the 2 hr. pp and fasting GC ratio (p = .39). There was significant difference between the stool frequency (p less than .01) and the prevalence of diarrhea (p less than .02) between pelvic irradiated patients and controls. The data suggest that bile acid malabsorption due to ileal dysfunction is not an inevitable late complication of pelvic irradiation and is not the major determinant in the pathophysiology of chronic radiation-induced diarrhea.

Perichiasmal tumors: diagnostic and prognostic features.

A review of 49 tumors compressing the intracranial optic nerve, optic chiasm, or optic tract revealed that the majority of patients had symptoms and signs of visual loss predominantly affecting one eye. Seventy-seven per cent of patients had a relative afferent pupillary defect (RAPD), and 96% had a hemianopic defect in at least one eye. All patients had either a RAPD or a hemianopic defect. The junctional pattern of visual field defects was nearly as common (39%) as the classic bitemporal pattern (46%). Many fields contained a mixture of nerve fiber bundle and hemianopic defects; the hemianopias tended to obscure the coexisting nerve fiber bundle defects. Poor preoperative acuity predicted a relatively poor postoperative acuity, but 95% of the patients had 20/40 or better acuity in at least one eye after operation.

Contributions to an environmental impact statement.

Assessment of the effects on land use, social, economic, historic and natural environment as a result of highway construction are discussed. Predictions of these effects on the various categories twenty years hence are also presented. Information of this type is a necessary segment of an environment impact study soas to conform to EPAand Department of Rransportation (DOT) guidelines.

The effect of a proposed transportation facility on noise levels in a suburban community.

A nine month study of current noise levels was made at twenty-two sites within a community in Eastern Pennsylvania to evaluate the noise pollution factors for a proposed highway. An attempt was made to correlateamnient noise levels for each day of theweek with each location. Computer programs were utilized for datareduction, statistical calculations, and prediction of future noise levels. The prediction analyses were composed of contour analyses, sensitive receptor sites analyses, and the "Do Nothing" analysis. Results indicated no noise pollution problems existed during the survey, but future noise levels may exceed Federal Standards for certain sections of the proposed alignments. Factors that cause the unacceptable future noise levels are identified and modifications may be incorporated for adherence to the standards.

Air pollution impact of a suburban highway segment.

Design traffic volumes, vehicle emission factors and meterological data are used to assess the impact of a suburban limited-access highway segment. Mesoscale effects are determined by emission inventory techniques. Microscale effects are determined using a pollutant dispersion model developed by the California Division of Highways. The air pollution impact of the highway segment is small, and should not be considered a significant criteria for decisions concerning construction of the highway.