Humeral stress remodelling locations differ in Thoroughbred racehorses training and racing on dirt compared to synthetic racetrack surfaces.

REASONS FOR PERFORMING STUDY: Veterinarians have observed a putative change in the location of humeral stress remodelling in Thoroughbred racehorses with change from dirt to synthetic racetrack surfaces. OBJECTIVES: To determine whether the location and severity of humeral stress remodelling differs between Thoroughbred racehorses exercising on dirt and synthetic racetrack surfaces, the potential significance of different locations of stress remodelling, and the potential usefulness of scintigraphy for prevention of complete humeral fracture. METHODS: Scintigraphic images of humeri from 841 Thoroughbred racehorses at 3 racetracks during 2 years before and after conversion from dirt to synthetic surfaces were evaluated for location and severity of lesions. The effects of surface on lesion distributions were examined using Chi-square or Fisher's exact tests. Archived fractured humeri were examined to determine the location and severity of stress remodelling associated with complete fracture. Databases were queried to determine whether racehorses with scintigraphic lesions suffered humeral fracture and whether racehorses with a complete humeral fracture had had a scintigraphic examination. RESULTS: Horses at synthetic racetracks had a greater proportion of distal humeral lesions, whereas horses at dirt racetracks had a greater proportion of caudoproximal lesions (P<0.001). Proximal lesions were more likely to be severe than distal lesions (P<0.001). Most complete fractures were associated with caudoproximal lesions, which were more often severe than distal lesions (P = 0.002). None of the horses with a scintigraphic lesion had a complete humeral fracture. None of the horses with a complete humeral fracture underwent scintigraphic examination. CONCLUSIONS: Race surface affected humeral scintigraphic lesion location and hence the location of stress remodelling. Lesion severity was associated with lesion location. Complete humeral fracture was associated with caudoproximal stress remodelling and lack of scintigraphic examination. POTENTIAL RELEVANCE: Risk for complete humeral fracture may be lower on synthetic surfaces than on dirt surfaces, and, by inference, for horses examined using scintigraphy.

Palosuran inhibits binding to primate UT receptors in cell membranes but demonstrates differential activity in intact cells and vascular tissues.

BACKGROUND AND PURPOSE: The recent development of the UT ligand palosuran (1-[2-(4-benzyl-4-hydroxy-piperidin-1-yl)-ethyl]-3-(2-methyl-quinolin-4-yl)-urea sulphate salt) has led to the proposition that urotensin-II (U-II) plays a significant pathological role in acute and chronic renal injury in the rat. EXPERIMENTAL APPROACH: In the present study, the pharmacological properties of palosuran were investigated further using a series of radioligand binding and functional bioassays. KEY RESULTS: Palosuran functioned as a 'primate-selective' UT ligand in recombinant cell membranes (monkey and human UT K(i) values of 4 +/- 1 and 5 +/- 1 nM), lacking appreciable affinity at other mammalian UT isoforms (rodent and feline K(i) values >1 microM). Paradoxically, however, palosuran lost significant (10- to 54-fold) affinity for native and recombinant human UT when radioligand binding was performed in intact cells (K(i) values of 50 +/- 3 and 276 +/- 67 nM). In accordance, palosuran also exhibited diminished activity in hUT (human urotensin-II receptor)-CHO (Chinese hamster ovary) cells (IC50 323 +/- 67 nM) and isolated arteries (K(b)>10 microM in rat aorta; K(b)>8.5 microM in cat arteries; K(b)>1.6 microM in monkey arteries; K(b) 2.2 +/- 0.6 microM in hUT transgenic mouse aorta). Relative to recombinant binding K(i) values, palosuran was subjected to a 392- to 690-fold reduction in functional activity in monkey isolated arteries. Such phenomena were peculiar to palosuran and were not apparent with an alternative chemotype, SB-657510 (2-bromo-N-[4-chloro-3-((R)-1-methyl-pyrrolidin-3-yloxy)-phenyl]-4,5-dimethoxybenzenesulphonamide HCl). CONCLUSIONS AND IMPLICATIONS: Collectively, such findings suggest that caution should be taken when interpreting data generated using palosuran. The loss of UT affinity/activity observed in intact cells and tissues cf. membranes offers a potential explanation for the disappointing clinical efficacy reported with palosuran in diabetic nephropathy patients. As such, the (patho)physiological significance of U-II in diabetic renal dysfunction remains uncertain.

A content analysis of television advertising for the Massachusetts Tobacco Control Program media campaign, 1993-1996.

Television advertising for the Massachusetts Tobacco Control Program (MTCP) was launched in 1993. The campaign's first three years were examined against an analytical framework based in behavioral change and communications theory. The most common focus in the 49 advertisements was tobacco industry practices, followed by health consequences for smokers and smoking prevention. Only one smoking prevention advertisement was targeted to children younger that age 13. Only four advertisements mentioned policy actions to reduce youth access or curtail exposure to environmental tobacco smoke. Only two advertisements listed the telephone number for the MTCP's smoking cessation program. The television campaign was uncoordinated with the MTCP's community-level programs.

Coccidioidomycosis in horses: 15 cases (1975-1984).

Fifteen confirmed cases of equine coccidioidomycosis that originated in California and Arizona were studied retrospectively. Age, breed, and sex varied among affected horses. The most common historical problems were chronic weight loss (53% of cases) and persistent cough (33% of cases). The most frequent physical examination abnormalities were related to the respiratory tract (60% of cases). In 27% of cases, horses had signs of musculoskeletal pain. Horses consistently had hyperproteinemia, hyperfibrinogenemia, leukocytosis, and neutrophilia. An antemortem etiologic diagnosis was made for 11 (73%) horses, all of which had positive serologic tests for coccidioidomycosis. Of the seropositive horses, 5 (46%) also had positive cultures for Coccidioides immitis. One horse died naturally. The other 14 were euthanatized. Prolonged treatment with specific antifungal agents was attempted in 4 horses without apparent benefit. Postmortem abnormalities included pulmonary parenchymal lesions (64% of cases), thoracic lymphadenopathy (57% of cases), hepatic parenchymal involvement (43% of cases), and osteomyelitis (29% of cases). The lesions were granulomatous or pyogranulomatous and C immitis was observed microscopically in 83% of cases.

Creating customer-oriented employees: the case in home health care.

Little empirical research has examined the organizational factors that influence the extent to which health care providers engage in customer-oriented behaviors. The authors examine the influence of role ambiguity, role conflict, and job satisfaction on the customer-oriented behaviors of home health care representatives. Managerial implications based on the study findings are discussed.

Golgi and immunocytochemical analysis of neurons in trigeminal subnucleus interpolaris: correlations with cellular localization of enkephalin.

Recent electrophysiological evidence shows that rostral levels of the trigeminal spinal complex are concerned with pain processing from receptive fields in the face and oral cavity. The ventrolateral quadrant of the subnucleus interpolaris contains concentrations of enkephalin, dynorphin, serotonin, substance P and GABA [Matthews M. A., Hernandez T. V. and Liles S. L. (1987) Synapse 1, 512-529; Matthews M. A., McDonald G. K. and Hernandez T. V. (1988) Somatosensory Res. 5, 205-217]. These transmitters have also been localized to the fusiform and stalked cells in Laminae I and II of the subnucleus caudalis [Basbaum A. I. and Fields H. L. (1984) A. Rev. Neurosci. 7, 309-338]. The present study compares Golgi impregnations of the subnucleus interpolaris with sections at the same levels immunoreacted against enkephalin to determine if comparable cells exist in the subnucleus interpolaris and if they occur predominantly in the ventrolateral quadrant of the subnucleus. Twelve, young adult cats were killed by perfusion, the brainstems removed and either processed for rapid Golgi impregnation or sectioned and immunoreacted for enkephalin using the avidin-biotin Vectastain method. Golgi impregnated tissue was sectioned in the coronal, transverse or sagittal plane to insure the most advantageous visualization of cells with a directional bias in their dendritic arbors. The subnucleus interpolaris contained several distinctive cell types. The predominant neuron throughout the subnucleus was the smooth pyramidal cell or multipolar cell, characterized by a large round soma (15-25 microns diameter) and a spherical dendritic arborization which allowed its identification in all planes of section. The second cell type was the fusiform cell which had a smaller ovoid soma (10-15 microns) with narrow, less ramified, dendritic arbors oriented dorsoventrally, thus giving a bipolar appearance. Fusiform cells were most concentrated along the lateral margin of the subnucleus interpolaris. Examination of sections at the same level reacted for enkephalin revealed cells with a bipolar appearance in these same locations. An additional cell population which tended to predominate in the lateral zone was the stalked cell. These displayed a rounded soma (12-20 microns) and were evident only in the transverse or sagittal plane. Two to four primary dendrites arose from the soma and extensively ramified into a dense spiny arbor directed into the body of the subnucleus interpolaris. Many examples contained enkephalin. Islet cells, characterized by a very small oval soma (6-12 microns) and dense, rostrocaudally oriented dendrites, were less common than stalked cells and were located deeper in the nucleus.(ABSTRACT TRUNCATED AT 400 WORDS)

Angiosarcoma following therapeutic irradiation.

This paper reports a case of angiosarcoma of the terminal ileum in a 66-year-old female. This angiosarcoma developed 8 years after postoperative irradiation for ovarian carcinoma. This case appears to be the sixth case of angiosarcoma arising at the site of therapeutic irradiation thus far reported in the literature. The fact that the angiosarcomas in these cases developed in anatomic sites, which are unusual for angiosarcomas in general, suggests that there is a cause-and-effect relationship between irradiation and angiosarcoma. Apart from the direct carcinogenic effect of irradiation, prolonged stimulation for tissue repair resulting from tissue damage secondary to irradiation-induced vascular changes may also play an etiologic role in the development of angiosarcomas in these cases.

Multiple myeloma and chronic lymphocytic leukemia in a single individual.

Chronic lymphocytic leukemia and multiple myeloma in a single individual is a rare occurrence; In previously reported cases, data relevant to the cional relationship between the two entities is not available. In this case, to our knowledge, the tenth reported, immunologic studies indicate that a chance association of two independent diseases has occurred rather than expansion of one single clone of Bcells at two morphological levels.