Synthesis, NMR characterization and divergent biological actions of 2'-hydroxy-ceramide/dihydroceramide stereoisomers in MCF7 cells.

A straightforward method for the simultaneous preparation of (2S,3R,2'R)- and (2S,3R,2'S)-2'-hydroxy-ceramides (2'-OHCer) from (2S,3R)-sphingosine acetonide precursors and racemic mixtures of 2-hydroxy fatty acids (2-OHFAs) is described. The obtained 2'-OH-C4-, -C6-, -C12-, -C16-Cer and 2'-OH-C6-dhCer pairs of diastereoisomers were characterized thoroughly by TLC, MS, NMR, and optical rotation. Dynamic and multidimensional NMR studies provided evidence that polar interfaces of 2'-OHCers are extended and more rigid than observed for the corresponding non-hydroxylated analogs. Stereospecific profile on growth suppression of MCF7 cells was observed for (2'R)- and (2'S)-2'-OH-C6-Cers and their dihydro analogs. The (2'R)-isomers were more active than the (2'S)-isomers (IC(50) ∼3 µM/8 µM and IC(50) ∼8 µM/12 µM, respectively), surpassing activity of the ordinary C6-Cer (IC(50) ∼12 µM) and C6-dhCer (IC(50) ∼38 µM). Neither isomer of 2'-OH-C6-Cers and 2'-OH-C6-dhCers was metabolized to their cellular long chain 2'-OH-homologs. Surprisingly, the most active (2'R)-isomers did not influence the levels of the cellular Cers nor dhCers. Contrary to this, the (2'S)-isomers generated cellular Cers and dhCers efficiently. In comparison, the ordinary C6-Cer and C6-dhCer also significantly increased the levels of their cellular long chain homologs. These peculiar anabolic responses and SAR data suggest that (2'R)-2'-OHCers/dhCers may interact with some distinct cellular regulatory targets in a specific and more effective manner than their non-hydroxylated analogs. Thus, stereoisomers of 2'-OHCers can be potentially utilized as novel molecular tools to study lipid-protein interactions, cell signaling phenomena and to understand the role of hydroxylated sphingolipids in cancer biology, pathogenesis and therapy.

Efficient assessment of social problem-solving abilities in medical and rehabilitation settings: a Rasch analysis of the Social Problem-Solving Inventory-Revised.

The Social Problem Solving Inventory-Revised Scale (SPSI-R) has been shown to be a reliable and valid self-report measure of social problem-solving abilities. In busy medical and rehabilitation settings, a brief and efficient screening version with psychometric properties similar to the SPSI-R would have numerous benefits including decreased patient and caregiver assessment burden and administration/scoring time. Thus, the aim of the current study was to identify items from the SPSI-R that would provide for a more efficient assessment of global social problem-solving abilities. This study consisted of three independent samples: 121 persons in low-vision rehabilitation (M age=71 years old, SD=15.53), 301 persons living with diabetes mellitus (M age=58, and SD=14.85), and 131 family caregivers of persons with severe disabilities (M age=56 years old, SD=12.15). All persons completed a version of the SPSI-R, Center for Epidemiological Studies Depression Scale (CES-D), and the Satisfaction with Life Scale (SWLS). Using Rasch scaling of the SPSI-R short-form, we identified a subset of 10 items that reflected the five-component model of social problem solving. The 10 items were separately validated on the sample of persons living with diabetes mellitus and the sample of family caregivers of persons with severe disabilities. Results indicate that the efficient 10-item version, analyzed separately for all three samples, demonstrated good reliability and validity characteristics similar to the established SPSI-R short form. The 10-item version of the SPSI-R represents a brief, effective way in which clinicians and researchers in busy health care settings can quickly assess global problem-solving abilities and identify those persons at-risk for complicated adjustment. Implications for the assessment of social problem-solving abilities are discussed.

Inhaled CD86 antisense oligonucleotide suppresses pulmonary inflammation and airway hyper-responsiveness in allergic mice.

The B7-family molecule CD86, expressed on the surface of pulmonary and thoracic lymph node antigen-presenting cells, delivers essential costimulatory signals for T-cell activation in response to inhaled allergens. CD86-CD28 signaling is involved in priming allergen-specific T cells, but it is unclear whether these interactions play a role in coordinating memory T-helper 2 cell responses. In the ovalbumin (OVA)-induced mouse model of asthma, administration of CD86-specific antibody before systemic sensitization suppresses inhaled OVA-induced pulmonary inflammation and airway hyper-responsiveness (AHR). In previously OVA-sensitized mice, systemic and intranasal coadministration of CD86 antibody is required to produce these effects. To directly assess the importance of pulmonary CD86 expression in secondary immune responses to inhaled allergens, mice were sensitized and locally challenged with nebulized OVA before treatment with an inhaled aerosolized CD86 antisense oligonucleotide (ASO). CD86 ASO treatment suppressed OVA-induced up-regulation of CD86 protein expression on pulmonary dendritic cells and macrophages as well as on recruited eosinophils. Suppression of CD86 protein expression correlated with decreased methacholine-induced AHR, airway inflammation, and mucus production following rechallenge with inhaled OVA. CD86 ASO treatment reduced BAL eotaxin levels, but it did not reduce CD86 protein on cells in the draining lymph nodes of the lung, and it had no effect on serum IgE levels, suggesting a local and not a systemic effect. These results demonstrate that CD86 expression on pulmonary antigen-presenting cells plays a vital role in regulating pulmonary secondary immune responses and suggest that treatment with an inhaled CD86 ASO may have utility in asthma and other chronic inflammatory lung conditions.

Anti-inflammatory activity of inhaled IL-4 receptor-alpha antisense oligonucleotide in mice.

The Th2 cytokines IL-4 and IL-13 mediate allergic pulmonary inflammation and airways hyperreactivity (AHR) in asthma models through signaling dependent upon the IL-4 receptor-alpha chain (IL-4Ralpha). IL-13 has been further implicated in the overproduction of mucus by the airway epithelium and in lung remodeling that commonly accompanies chronic inflammation. IL-4Ralpha-deficient mice are resistant to allergen-induced asthma, highlighting the therapeutic promise of selective molecular inhibitors of IL-4Ralpha. We designed a chemically modified IL-4Ralpha antisense oligonucleotide (IL-4Ralpha ASO) that specifically inhibits IL-4Ralpha protein expression in lung eosinophils, macrophages, dendritic cells, and airway epithelium after inhalation in allergen-challenged mice. Inhalation of IL-4Ralpha ASO attenuated allergen-induced AHR, suppressed airway eosinophilia and neutrophilia, and inhibited production of airway Th2 cytokines and chemokines in previously allergen-primed and -challenged mice. Histologic analysis of lungs from these animals demonstrated reduced goblet cell metaplasia and mucus staining that correlated with inhibition of Muc5AC gene expression in lung tissue. Therapeutic administration of inhaled IL-4Ralpha ASO in chronically allergen-challenged mice produced a spectrum of anti-inflammatory activity similar to that of systemically administered Dexamethasone with the added benefit of reduced airway neutrophilia. These data support the potential utility of a dual IL-4 and IL-13 oligonucleotide inhibitor in allergy/asthma, and suggest that local inhibition of IL-4Ralpha in the lung is sufficient to suppress allergen-induced pulmonary inflammation and AHR.

Barriers to safer sex practices among African American college students.

African American college students are among the age group of African Americans with significantly higher heterosexual transmission of HIV. It has been projected that young African Americans of college age will be the next group to be affected by the HIV/AIDS epidemic. The goals of this research were to identify barriers to African American college students engaging in safer sex behaviors; determine whether barriers to safer sex differ for African American men versus African American women; and use the findings to help identify strategies likely to promote safer sex practices among African American college students. The Nominal Group Technique (NGT) was used to collect the information. The results yielded the following themes. For males and females, the combined themes, negative views of condoms were ranked the most important with a score of 70. Trust issues were ranked the second most important with a total score of 47. The third highest ranked theme was living for the moment with a total score of 43. The fourth highest ranked theme was feeling invincible with a total score of 42. The authors provide a number of recommendations for consideration in the development of HIV prevention programs for African American college students.