Shear wave elastography safety in fetus: A quantitative health risk assessment.

PURPOSE: To identify the effects of shear wave elastography in the fetus for evaluation in widespread use. MATERIALS AND METHODS: The Health Risk Assessment method proposed by the National Research Council was used with literature to evaluate the safety of shear wave elastography for the fetus regarding its potential effects in human tissues. RESULTS: The experimental and epidemiologic data from 25 articles showed that shear wave elastography maintained the same thermal effect as pulsed Doppler ultrasound already authorized in obstetrics, and that cavitation effect on fetal tissue is improbable. Nonetheless, the vibratory character of shear waves could induce displacement of fetal tissue while potential effects of very short duration energy peaks of the radiation force focused wave front remain unknown. CONCLUSION: The actual knowledge does not provide enough information to assess the effects of shear wave elastography on fetal tissues, thus these points have to be explored by further experimental studies.

Influence of region of interest size and ultrasound lesion size on the performance of 2D shear wave elastography (SWE) in solid breast masses.

AIM: To evaluate the influence of the region of interest (ROI) size and lesion diameter on the diagnostic performance of 2D shear wave elastography (SWE) of solid breast lesions. MATERIALS AND METHODS: A study group of 206 consecutive patients (age range 21-92 years) with 210 solid breast lesions (70 benign, 140 malignant) who underwent core biopsy or surgical excision was evaluated. Lesions were divided into small (diameter <15 mm, n=112) and large lesions (diameter ≥15 mm, n=98). An ROI with a diameter of 1, 2, and 3 mm was positioned over the stiffest part of the lesion. The maximum elasticity (Emax), mean elasticity (Emean) and standard deviation (SD) for each ROI size were compared to the pathological outcome. Statistical analysis was undertaken using the chi-square test and receiver operating characteristic (ROC) analysis. RESULTS: The ROI size used has a significant impact on the performance of Emean and SD but not on Emax. Youden's indices show a correlation with the ROI size and lesion size: generally, the benign/malignant threshold is lower with increasing ROI size but higher with increasing lesion size. CONCLUSIONS: No single SWE parameter has superior performance. Lesion size and ROI size influence diagnostic performance.

Case management of the elderly in a health maintenance organization: the implications for program administration under managed care.

Kaiser Permanente initiated a two-year demonstration ambulatory case management program in its Ohio region to evaluate five outcomes: perceived health status, functional status, and satisfaction with care, service use, and service costs. Expected results were not consistently obtained for the five outcome measures. Treatment group members did not, however, experience the functional status impairments or decline in health status perceptions reported by the control group during the study period. The unexpected finding that costs were not affected may be attributed to the type of case management intervention used in the demonstration program. This study is broadly applicable to managed care settings facing the challenge of developing programs to minimize the risk for bearing the costs of the Medicare beneficiaries' overall health when all services are not covered. Managed care administrators should be favorably disposed to implementing a case management model with the potential for affecting functional status, the most significant predictor of expensive continuing care for this cohort of Medicare beneficiaries, while working to develop more effective protocols and resource control strategies.

Transboundary Conservation: An Ecoregional Approach to Protect Neotropical Migratory Birds in South America

/ Future conservation efforts will need to transcend geopolitical boundaries in efforts to protect entire landscapes and ecosystems. Neotropical migratory birds are as a group a useful conservation tool for linking diverse landscapes and people due to their dependence on multiple habitats, sensitivity to habitat changes, and universal public appeal. The conservation of neotropical migrants can therefore function as a powerful hemispheric umbrella for ecosystem protection. Efforts to protect neotropical migratory birds on their nonbreeding grounds have traditionally been focused on Mexico, Central America, and the Caribbean. To assess the importance of South America to neotropical migrants, an ecoregional classification system was used to determine species distributions in the Andean/Southern Cone Region (Bolivia, Colombia, Ecuador, Paraguay, Peru, and Venezuela). The occurrence of migrants in protected areas that are part of The Nature Conservancy's Parks in Peril program was also assessed. Of the 406 neotropical migrant species, nearly one third (132) occur as regular nonbreeding residents in the region and for almost half of these species (53), South America is their main nonbreeding ground. All Parks in Peril sites were found to harbor neotropical migrants. Forty-eight species (36%) have declining long-term North American Breeding Bird Survey population trends and/or high Partners in Flight concern scores and thus are of significant conservation concern. Most importantly, 29 species (22%) of conservation concern use South America as their primary nonbreeding ground, indicating a need for focused conservation action. The nature of the ecoregional approach used in this endeavor makes future prioritization of ecoregions and conservation strategies for neotropical migrants across national boundaries possible. The ability to link diverse landscapes using a common element such as migratory birds allows for unique transboundary partnerships and opportunities for habitat conservation, which support the goal of the Conservancy's new Migratory Bird Initiative.KEY WORDS: Neotropical migratory birds; Transboundary conservation; Ecoregions; Protected areas; South America

In vitro binding of Candida albicans yeast cells to human fibronectin.

The binding of Candida albicans yeast cells to human fibronectin (Fn), a major glycoprotein of mammalian cells, was studied using an in vitro assay. Adherence was quantitated in microtiter dishes coated with Fn to which radiolabeled yeast cells were added. Under optimum conditions of the assay, i.e., 1 mM CaCl2 and 70 micrograms Fn protein, approximately 40% of the radiolabeled yeast cells adhered to the Fn. Adherence to Fn was greater at 30 degrees C than at 4 degrees C and was greater with viable yeast cells than with heat-killed cells. Candida albicans (two strains) and C. tropicalis adhered to Fn to a greater extent than C. pseudotropicalis, C. krusei, or Saccharomyces cerevisiae. Pretreatment of C. albicans with chymotrypsin, pronase, or papain, but not pepsin, decreased adherence to Fn. Blocking experiments using mannan, sugars, or amino sugars were carried out by preabsorbing the Fn with each of the above-mentioned compounds. Candida mannan blocked adherence of C. albicans to Fn. The mannan effect was dose dependent. However, adherence of C. albicans to Fn was not significantly reduced by mannose, glucose, or several other sugars. The role of FN as a receptor for the binding of C. albicans yeast cells to buccal and vaginal epithelial cells was investigated also using an in vitro assay. We determined, using indirect fluorescent antibody techniques, that both buccal and vaginal epithelial cells possessed Fn. In addition, yeast cells, when pretreated with Fn, showed reduced adherence with buccal and vaginal cells when compared with nontreated cells. These studies may indicate a role for Fn in the adherence of C. albicans to buccal and vaginal epithelial cells.

Platelet interactions with Candida albicans.

The interaction of human platelets and Candida albicans was studied. Platelet-rich plasma was obtained from freshly drawn blood or outdated platelet concentrates. From the platelet-rich plasma, a platelet extract was derived which stimulated germ tube formation by C. albicans when incubated with yeast cells at 37 degrees C. The active component(s) was heat stable, trypsin sensitive, and ribonuclease and deoxyribonuclease insensitive, and possessed cationic properties since it readily attached to carboxymethyl-Sephadex. The active component(s) seemed to bind to heparin also, since germ tube-promoting activity was eluted from a heparin-cyanogen bromide-activated Sepharose 4B column. In addition, platelet-derived growth factor (Collaborative Research, Inc.) stimulated germination when incubated with low amounts (0.4% final concentration) of bovine calf serum. The aggregation of platelets, prepared as platelet-rich plasma by C. albicans cell wall or alkali-extracted cell wall fractions, was also studied. Aggregation of platelets was observed when cell wall or cell wall fractions were incubated with platelet-poor plasma at 37 degrees C for 20 min and then added to platelet-rich plasma. The component of platelet-poor plasma which promoted aggregation of platelets by C. albicans cell wall or alkali-extracted fractions was inactivated at 56 degrees C (30 min) and by cobra venom factor, indicating a role for the alternate complement pathway in the aggregation response.