PubMed Health⌕ Search

Biomedical subjects

E Felder

Publications and source records attributed to E Felder.

At least 37 records · Page 2Linked to original sources
PubMed1990

Comparison of Gd-BOPTA with Gd-DTPA in MR imaging of rat liver.

A new lipophilic compound, gadolinium benzyloxypropionictetraacetate (BOPTA), with a high rate of biliary excretion was assessed as a magnetic resonance (MR) hepatospecific contrast-enhancing agent and compared with Gd-DTPA (diethylenetriaminepentaacetic acid) in MR imaging of normal rats. T1-weighted spin-echo images obtained before and after administration of each contrast agent at doses of 0.25, 0.5, and 1.0 mmol/kg showed greater enhancement of the liver with Gd-BOPTA than with Gd-DTPA, with the advantage more evident at lower doses. Images obtained with an inversion recovery sequence at the null value of rat liver parenchyma after injection of 0.1- and 0.5-mmol/kg doses of the contrast agent provided better evidence of the greater and longer-lasting hepatic enhancement due to Gd-BOPTA when compared with that of Gd-DTPA. Gd-BOPTA is a potentially good contrast agent for obtaining prolonged enhancement of the liver, permitting studies during the long time needed to acquire conventional T1-weighted images.

Acetates↗
PubMed1990

Baccalaureate and associate degree student nurses' cultural knowledge of and attitudes toward black American clients.

The purpose of this study was to investigate the effect of cultural diversity education in nursing on baccalaureate and associate degree students' cultural knowledge of and attitudes toward black American clients. Cultural diversity education in nursing information processing, and attitude concepts (Fishbein & Ajzen, 1975) provided the conceptual framework. The sample consisted of 110 baccalaureate and associate degree senior and freshmen students from National League for Nursing accredited schools of nursing. Each school's dean confirmed that cultural diversity educational experiences were included in the curricula. The findings indicated that the group of associate degree students, which included a large number of various ethnic students, had higher cultural knowledge of black American clients then the baccalaureate degree students, who had less ethnic variance. However, adjustment for the ethnic variable was not significant (F(1,1) = 12.5, p less than .001). There were no differences in the attitudes toward black American clients between the two groups of students. The score ratings for cultural knowledge of (m = 66.90 on a scale of 0 to 100), and attitude toward (m = 35.40 on a scale of 7 to 56 points) black American clients were low in each group of students. Implications are for increased and improved cultural content in nursing education and alternative methods of teaching black American cultural content.

Adolescent↗
PubMed1990

The nursing cultural center. A design for cultural diversity.

The rationale for the development of the Nursing Cultural Center (NCC) at a leading mid-western university is discussed by the author. Both the goals and purposes of the NCC within the framework of the mission of the University of Wisconsin-Milwaukee and the surrounding community are emphasized to illustrate how two basic strategies are used to facilitate the accomplishment of these goals and purposes. These strategies are processing cultural health information and implementing the Cultural Diversity Practice Model (CDPM). The NCC is a cultural health informational center which facilitates the application of the Cultural Diversity Practice Model developed by the author.

Academies and Institutes↗
PubMed1990

Self-care agency and blood pressure control.

This research examined whether blood pressure measurement relates to an individual Self-Care Agency's (SCA) capabilities (self-concept, knowledge, and initiative) to exercise self-care. A sample of 110 hypertensive high-risk urban black Americans (61 males and 49 females) with a mean age of 46 years (range 18-75), was administered the 43 item 'Exercise of Self-Care Agency' scale and a demographic/health questionnaire. The blood pressure (BP) of each participant was measured at the time of the survey. A large number of subjects (72%) had normal BP and 80% low SCA capability scores. Twenty-eight percent had abnormal BP and 21% had high SCA scores. Blood pressure did not relate to self-care agency. The SCA subconstruct, 'Initiative' was significantly related to normal BP (r = 0.3354, P = 0.006). Self-care agency was inversely associated with obesity, cigarette smoking and excessive salt use. These findings suggest a deficit relationship between SCA and therapeutic self-care demand among urban black Americans who are at high risk for hypertension.

Adolescent↗
PubMed1990

[A comparative study between Gd-BOPTA, a biliary excretion contrast medium, and Gd-DTPA in the magnetic resonance imaging of the rat liver].

A new lipophilic compound, Gd-BOPTA, presenting a high rate (38.6%) of biliary excretion was tested as an hepato-specific MR contrast agent. Its adequacy was compared to that of Gd-DTPA in laboratory animals. T1-weighted spin-echo sequences (TR 220 ms, TE 20 ms) both before and after the administration of the 2 contrast agents (doses: 0.25, 0.5, and 1.0 mmol/kg) showed better liver enhancement with Gd-BOPTA than with Gd-DTPA. Gd-BOPTA superiority was more evident at lower doses, while at 1.0 mmol/kg a comparable enhancement was achieved. Inversion recovery sequence at the T-null of liver parenchyma before contrast (TR 800 ms, TE 30 ms, TI 100 ms) was performed after the injection of 0.1 and 0.5 mmol/kg of Gd-DTPA and Gd-BOPTA. This sequence allowed the good and long-lasting liver enhancement achieved with Gd-BOPTA to be even better demonstrated, while Gd-DTPA provided only a slight and early enhancement with 0.1 mmol/kg and returned to baseline values 60' after the injection of the highest dose (0.5 mmol/kg). Gd-BOPTA proved to be a good contrast agent to obtain prolonged liver enhancement, thus providing the radiologist with the long time needed to acquire conventional T1-weighted pulse sequences.

Acetates↗
PubMed1988

Molecular rearrangement of 5-(a-hydroxy-alkanoylamino)-2,4,6-triiodo-isophthalic acid amides.

Iomeprol, a new nonionic contrast agent, undergoes in alkaline solution a Smiles-type intramolecular rearrangement to give 5-methylaminocarbonylmethoxy-2,4,6-triiodoisophthalic acid-bis-(2,3-dihydroxypropylamide). The rearranged product was isolated and its structure confirmed by spectra and by synthesis. The reaction is reversible and could be extended to some structurally related compounds.

Chemical Phenomena↗
PubMed1988

A liposomal contrast agent. Preliminary communication.

Iopamidol-carrying liposomes were studied as potential hepatosplenographic contrast agents. Large unilamellar vesicles (0.3-1 mu) prepared from phosphatidylcholine:Dipalmotylphosphatidic acid (PC:DPPA) 9:1 and 300 MgI/mL iopamidol solution showed favorable entrapment measured as mg entrapped iodine/mg lipids (I/L). The effect of extrusion through polycarbonate membranes on liposome characteristics and in vivo distribution was investigated. Extrusion above the transition temperature of lipids reduced the average size and size distribution and increased the I/L ratio. Distribution studies of extruded and nonextruded liposomes in rats demonstrated different behavior of the preparations; extruded liposomes showed higher spleen uptake than did unextruded, while liver uptake was comparable; lung entrapment, observed with unextruded particles, was almost eliminated with extruded liposomes. Preliminary imaging studies in rats were carried out at a dose of 250 mgI/kg; typical computed tomography (CT) scans of the liver demonstrated contrast enhancement of greater than or equal to 60 HU from 90' up to 240' after injection.

Animals↗
PubMed1988

B-19036, a potential new hepatobiliary contrast agent for MR proton imaging.

B-19036 is an octadentate chelate of the paramagnetic ion Gd3+ under investigation as a proton relaxation enhancer (PRE) in magnetic resonance (MR) proton imaging. Its relaxivity was determined at 0.5 T by pulse spectrometry in various biologic fluids and in liver tissue homogenate. The ligand selectivity versus gadolinium was assessed in comparison with that versus other ions of biologic interest. Acute toxicity was determined after intravenous (IV) and intracerebral administration to mice. Pharmacokinetic studies conducted in rats indicated that unlike Gd-DTPA, where excretion is exclusively renal, biliary route plays a significant role in the excretion of B-19036, suggesting its possible use for hepatobiliary imaging.

Acetates↗
PubMed1986

Yeast pre-messenger RNA splicing efficiency depends on critical spacing requirements between the branch point and 3' splice site.

In the yeast Saccharomyces cerevisiae the 5' and 3' splice junctions and the internal branch acceptor site (TACTAAC box) are highly conserved intron elements. Analyses of mutants have demonstrated the importance of each of these elements in the splicing process. In the present report we show by three different analytical approaches (splicing-dependent beta-galactosidase expression, in vitro splicing assays and in vivo RNA analyses) that at least two of these elements (the TACTAAC and 3' splice signals) also have to fulfill certain spacing requirements to allow efficient splicing to occur. In particular, the spacing of the 3' splice site from the 2'-5' branch site is a critical factor in determining the efficiency for completion of the final reactions of splicing, intron release and exon-exon joining. Whereas insertions within this region have little or no effect on the first reactions in splicing (the 5' cleavage and 2'-5' branch formation), they dramatically affect the efficiency of the final reactions. In contrast, a 15-base deletion between these two sites has no detectable effect on splicing efficiency. We also show that the 5' cleavage and branch formation can take place, albeit inefficiently, in transcripts in which all of the yeast sequences downstream of the branch site have been replaced by Escherichia coli sequences. We conclude from these studies that, in yeast, the 5' and 3' splice sites are recognized independently from one another, but always in conjunction with the TACTAAC signal.

Base Sequence↗