High resolution MR imaging of joint degeneration in the knee of the STR/ORT mouse

MR imaging of the knee joints of the mouse at 2.35 T produces an in-plane resolution of 35 x 70 microns and a slice thickness of 600 microns from the sagittal and coronal planes, in less than 60 min. In normal, live DBA mice, which have no known pathology, the images clearly resolve many joint structures, such as the cruciate ligaments, menisci, and articulating surfaces of the femur and tibia. Gross pathological changes were identified first in excised knees from cadaver mice of the STR/ORT strain. Males of this strain spontaneously exhibit rapid joint degeneration with increasing age compared to females, in which much milder symptoms develop more slowly. Thickening of the patellar tendon, displacement of the patella, deformity, and sclerosis were clearly distinguishable in males compared with females older than 7 mo of age. The same degenerative features were evident in MR images of the knees of the live male but not female STR/ORT mice of this age, indicating that it would be possible to monitor longitudinally by MR imaging progressive development of joint changes in this osteoarthritic model.     

Culture of urinary sediment for the diagnosis of gonorrhoea in women

1,001 consecutive women seen in a V.D. clinic were screened for gonorrhoea by cultures of urinary sediment, the endocervix, and anal canal. Recovery of Neisseria gonorrhoeae on culture of urinary sediment was 81-7 per cent. as productive as culture of the endocervix, and 79-2 per cent. compared to endocervical and anal canal culturing. Urogenital symptoms were present in 55-1 per cent. of women with negative cultures and 64-6 per cent. of those with gonorrhoea. A complaint of dysuria increased the likelihood of a positive urinary sediment or endocervical culture. Culture of urinary sediment is less sensitive than culture of the endocervix. However, the ease with which specimens are obtained and the relative simplicity of the technique could make this method an acceptable tool for screening large numbers of women for gonorrhoea.     

Aerial Assessment of Ephemeral Gully Erosion from Agricultural Regions in the Pacific Northwest

Soil erosion from agricultural areas continues to be problematic in terms of both financial and environmental measures. Ephemeral gullies contribute to the soil loss both by the volume of sediment eroded from the gullies and because they act as delivery channels for surface erosion. High resolution aerial imagery was used to quantify the amounts and locations of ephemeral gullies in the subbasins of the Potlatch River system. Areal ephemeral gully erosion rates varied from 33.6?mt/km2 (0.15 U.S. t/acre) in the Big Bear Creek Subbasin to 88.4?mt/km2 (0.39 U.S. t/acre) in the Middle Potlatch Creek Subbasin representing 2.3–7.7% of the total surface sediment load. An erosion potential index was proposed to assist resource managers predict gully locations at the watershed scale using readily available remote sensing and geographic information system layers.     

Theory of diaphragm structure and shape

The muscle bundles of the diaphragm form a curved sheet that extends from the chest wall to the central tendon. Each muscle bundle exerts a force in the direction of its curvature; the magnitude of this force is proportional to the curvature of the bundle. The contribution of this force to transdiaphragmatic pressure is maximal if the direction of bundle curvature is orthogonal to the surface and the curvature is maximal. That is, the contribution of muscle tension to transdiaphragmatic pressure is maximal if the muscle bundles lie along lines that are both geodesics and lines of maximal principal curvature of the surface. A theory of diaphragm shape is developed from the assumption that all muscle bundles have these optimal properties. The class of surfaces that are formed of line elements that are both geodescis and lines of principal curvature is described. This class is restricted. The lines that form the surface must lie in planes, and all lines must have the same shape. In addition, the orientation of the lines is restricted. An example of this class that is similar to the shape of the canine diaphragm is described, and the stress distribution in this example is analyzed.     

Evaluation of cardiac 31P magnetic resonance spectroscopy: reviewing NMR principles

Methylguanidine, guanidinoacetic acid and guanidinosuccinic acid are endogenous substances in body tissues. Extremely high levels of these substances are known to be related to the pathogenesis of epilepsy and renal failure such as uremia. In this study it was demonstrated that methylguanidine, guanidinoacetic acid and guanidinosuccinic acid, and arginine generate hydroxyl radicals in aqueous solution. These findings suggest that a high level of guanidino compounds accumulating near or within cells such as neurons (in an epileptogenic focus) or nephrons (in uremic patients) may cause free radical damage leading to these clinical disorders. Arginine may have a similar role in the pathogenesis of hyperarginemia.     

Analytical development of electrospray and nanoelectrospray mass spectrometry in combination with liquid chromatography for the characterization of proteins

Microbial pathogens may be transmitted to humans via food animals and food animal products. A quick reference table is presented to provide easy access to food safety information related to the major food animal product areas. Included in the table are the pathogens, mode of transmission, public health impact, and control and prevention strategies for poultry, beef, dairy products, and pork.     

Human leukocyte derived interferon-alpha in a hydrophilic gel for the treatment of intravaginal warts in women: a placebo-controlled, double-blind study

Persistent polychlorinated biphenyl (PCB) metabolites were studied with respect to their interaction with the human glucocorticoid receptor (GR). 3-Methylsulphonyl-2,5,6,2',4',5'-hexachlorobiphenyl (3-MeSO2-CB149) was shown to compete with 3H-dexamethasone for binding to the GR, with an IC50 (concentration that inhibits 50%) of approximately 1 microM. Using GRAF cells expressing human GR, glucocorticoid responsive element, and a reporter enzyme, we demonstrated that 3-MeSO2-CB149 functionally acts as an antagonist at the GR (IC50 = 2.7 microM). In accordance with the receptor binding, the antagonism mainly appeared to be of a competitive nature. When studying the competitive binding of 24 methylsulfonyl PCBs (relative to dexamethasone) to GR from mouse liver cytosol, seven compounds had a higher affinity to GR than 3-MeSO2-CB149. Structure-activity relationship studies indicated that the presence of three chlorine atoms in the ortho-position and chlorine and methyl sulfone groups on either end of the molecule (4 and 4'-position) increased the affinity to GR. The relevance of this finding for human health is not known, but PCB methyl sulfones are ubiquitous pollutants present in mother's milk. The results stress the need for studying endocrine disruptors that affect hormonal systems other than sex and thyroidogenic hormones.