Phase contrast X-ray imaging of mice and rabbit lungs: a comparative study.

The significant degree of X-ray phase contrast created by air-tissue interfaces, coupled with the poor radiographic contrast of conventional chest radiographs, makes the inflated lung an ideal candidate for investigating the potential diagnostic improvement afforded by phase contrast X-ray imaging. In small animals these methods highlight the lung airways and lobe boundaries and reveal the lung tissue as a speckled intensity pattern not seen in other soft tissues. We have compared analyser-based and propagation-based phase contrast imaging modalities, together with conventional radiographic imaging, to ascertain which technique shows the greatest image enhancement for various lung sizes. The conventional radiographic image of a mouse was obtained on a Siemens Nova 3000 mammography system, whilst phase contrast images of mice and rabbit chests were acquired at the medical imaging beamline (20B2) at the SPring-8 synchrotron radiation research facility in Japan. For mice aged 1 day, 1 week and 1 month old it was determined that analyser-based imaging showed the greatest overall image contrast, however, for an adult rabbit both techniques yielded excellent contrast. The success of these methods in creating high quality images for rabbit lungs raises the possibility of improving human lung imaging using phase contrast techniques.

Case study: a unique approach to compliance in a patient with venous ulcers.

Lower extremity venous ulcers affect 500,000 to 700,000 Americans, with a 10-week outpatient treatment cost of $1327 to $5289. Recurrence rates are reported as 57% within 10.4 months. Many types of treatments are available, but the most successful treatment continues to be the most basic-elevation and compression. Innovative ideas to increase patient compliance can be the key to successful therapy.

The effect of gadolinium contrast media on radioiodine uptake by the thyroid gland.

OBJECTIVE: Patients with thyroid cancer may require detailed anatomic imaging before 131I therapy. Imaging by contrast-enhanced CT is contraindicated because it may result in saturation of tissues with iodine, decreasing the avidity of thyroid or thyroid cancer cells to subsequent radioiodine for extended intervals. Gadolinium-enhanced MRI offers an alternative to CT for detailed anatomic imaging. However, it is not known whether gadolinium contrast affects uptake of iodine by the thyroid gland since lanthanides affect ion transport in a variety of ways. The objective of this project was to determine whether the gadolinium MRI contrast injection alters thyroid uptake of radioiodine. METHODS: Radioiodine uptake by the thyroid gland was measured at 6 h and 24 h after the oral administration of 100 microCi 123I-Na-I. Three to seven days later, a standard dose (20 mL) of Magnevist (gadolinium DTPA) was administered intravenously. Another capsule of 100 microCi 123I Na-I immediately was given orally, and 6-h and 24-h radioiodine uptake by the thyroid gland was again measured and compared to baseline values. RESULTS: There was no statistically significant difference in uptake of radioiodine uptake by the thyroid gland between baseline values and those acquired immediately after the administration of Magnevist. CONCLUSION: Contrast-enhanced MRI may be safely performed before contemplated determinations of thyroid uptake of radioiodine, 131I therapy for hyperthyroidism, and postsurgical 131I imaging and therapy for well-differentiated thyroid cancer.

Active immunization against follistatin and its effect on FSH, follicle development and superovulation in heifers.

Ovaries of heifers were examined daily by transrectal ultrasonography for one interovulatory interval before initiation of immunizations (control cycle, n = 14), and again after the fifth immunization with a sham-vaccine (Freund's adjuvant only; n = 7) or a recombinant porcine follistatin-vaccine (1 mg per vaccination; n = 7) to study the effect of follistatin on follicle dynamics. After the fifth immunization, 4 heifers had a follistatin antibody titer of > or = 1:3200, while the remaining 3 heifers had a titer of only 1:400. At wave emergence, the total number of follicles and the number of small follicles (3 to 5 mm) were higher (P < 0.05) in the follistatin group than in the control and sham groups. In addition, high-titer heifers had a greater (P < 0.05) number of follicles (total and small) per day than low-titer heifers. Plasma concentration of FSH remained unchanged after sham- or follistatin-immunization. Sham- and follistatin-vaccinated heifers were then given half the standard superovulatory dose of Folltropin (200 mg of FSH) 14 d after the sixth immunization. More ovulations were detected in follistatin- (10.9 +/- 2.4) than sham- (5.0 +/- 0.8) vaccinated heifers (P < 0.05). Moreover, heifers with a high titer had more ovulations (P < 0.02) than heifers with a low titer (15.0 +/- 2.5 vs 5.3 +/- 1.2). The number of ova-embryos classified as fertilized:unfertilized and transferable:discarded, and quality of the embryos were similar between sham and follistatin groups. By 80 d after the last immunization, when antibody titers were undetectable in the follistatin group, there was no difference in superovulatory response between sham (6.7 +/- 1.6) and follistatin (7.6 +/- 1.6) groups. In summary, follistatin immunization was associated with an increase in the number of small follicles at the time of wave emergence and a greater response to superovulatory treatment. The results suggest that effects of follistatin on follicular dynamics were not mediated through changes in pituitary secretion of FSH.

Transcription of a novel mouse semaphorin gene, M-semaH, correlates with the metastatic ability of mouse tumor cell lines.

In the attempt to identify genes associated with metastasis, we have compared gene expressions of two metastatic cell lines, 4T1 and 66cl4, and one noninvasive, nonmetastatic cell line, 67NR, which originate from the same mouse mammary adenocarcinoma. Using the technique of differential display, we identified a novel member of the semaphorin/collapsin family in the two metastatic cell lines. We have named it M-semaH. Northern hybridization to a panel of tumor cell lines revealed transcripts in 12 of 12 metastatic cell lines but in only 2 of 6 nonmetastatic cells and none in immortalized mouse fibroblasts. To our knowledge, this is the first time that the expression of a semaphorin gene has been shown to correlate positively with tumor progression. We have characterized two transcripts present in the tumor cells. One transcript, M-semaH-v, is a putative splice variant, which is less abundant in normal tissue and lacks 478 bp in the 3' untranslated region. Both transcripts encode the same 775 amino acids with the features of a secreted glycoprotein. Northern analysis suggests that the M-semaH gene is involved in embryonic development and in situ hybridization locates the M-semaH expression to the developing lungs, to developing skeletal elements, and to the ventral horns of the developing neural tube.

Carotid endarterectomy clinical pathway: a nursing perspective.

The changing demands of the health care environment require that more effective treatments be used to lower costs and decrease length of stay. Clinical pathways provide a detailed plan of care and are one method available to achieve these goals. The carotid endarterectomy pathway was selected as the first pathway developed because of the short length of stay and its history of few complications. The process of developing the pathway gave the multidisciplinary team a chance to rethink individual practices and rid themselves of old habits. The results showed a decreased length of stay, lower costs, and maintenance of high patient outcomes. The positive impact also required changes in teaching tools.

Erythromelalgia--a case study.

Erythromelalgia is a rare syndrome characterized by pain, redness, and heat involving the lower and, less frequently, the upper extremities. Symptoms occur with local or environmental stimulation and may be mild for years or become disablingly severe. A finding of relief with ice-water immersion helps distinguish erythromelalgia from disorders such as causalgia and reflex sympathetic dystrophy. Erythromelalgia may be classified in three ways: (1) early-onset, (2) adult-onset aspirin-sensitive, and (3) adult-onset non-aspirin-sensitive. Treatment options, which include medication, sympathetic blocks, and surgery, are determined by classification.

Fluid therapy with specific mucopolysaccharides. A new approach to control diarrhea.

An evaluation is given of the shortcomings of existing oral fluid therapies and their consequences: lack of protection of the intestinal wall and the supply of unabsorbed carbohydrates to the large intestine. The inclusion of specific mucopolysaccharides having a polyxylose backbone and galactose end residues in the side chains seems to offer effective protection of the intestinal wall. A trial conducted in experimentally infected calves (E. coli) shows that this concept of oral fluid therapy limits the number of diarrhea days and induces better growth in calves; a more complete glucose absorption and limitation of the supply of unabsorbed carbohydrates to the large intestine was shown in a trial conducted in human patients with a rotavirus enteritis.

Multiple Fourier transform generation for coherent optical correlators.

An interferometrically generated off-axis holographic optical element images a laser diode light source to a 3 x 5 point array through 10 cm of glass. The element also reduces the elliptical beam cross section from 3:1 to 1.5:1.

Holographic Doppler imaging of rotating objects.

The Doppler frequency shift of coherent light reflected from rotating objects is used to obtain one-dimensional resolution much greater than the classical limit for aperture limited imaging systems. The Doppler information is processed by using the temporal and spatial filtering properties of modulated-referencewave holograms. The holographic reconstruction is a superresolved image. Resolution improvements greater than 200 times the classical limit were obtained at good signal-to-noise ratios.