Vitamin B12 and Homocysteine Associations with Gait Speed in Older Adults: The Baltimore Longitudinal Study of Aging.

OBJECTIVES: This study aimed to assess the independent associations of serum levels of vitamin B12 and plasma concentrations of homocysteine with gait speed decline. DESIGN, SETTING, PARTICIPANTS: This study utilized longitudinal analysis of participants 50 years or older from The Baltimore Longitudinal Study of Aging, N=774. MEASUREMENTS: Gait speed (m/s) was assessed using the 6-meter usual pace test. Vitamin B12 and homocysteine concentrations were collected using standard clinical protocols. Linear mixed effects regression was stratified by baseline age category (50-69, 70-79, and ≥80 years old). RESULTS: Mean follow-up time for the total study sample was 5.4 ± 2.0 years. No association between vitamin B12 and gait speed decline over the follow-up time for any age group was found. Elevated homocysteine concentrations were associated with decline in gait speed after adjustment for covariates (50-69: ß= -0.005, p=.057; 70-79: ß= -0.013, p<.001, ≥80: ß= -0.007, p=.054). CONCLUSION: Homocysteine and vitamin B12 are inversely related, yet only homocysteine was associated with gait speed decline in this population of healthy older adults. Given these results, future research should be directed towards investigating the relationship in populations with greater variation in vitamin B12 concentrations and other mechanisms influencing homocysteine concentrations.

Suppression of ovarian cancer growth via systemic administration with liposome-encapsulated adenovirus-encoding endostatin.

Gene therapy using adenoviral vector containing the endostatin gene is a promising strategy for advanced cancers. However, host immune response to adenovirus and the lack of the requisite coxsackie-adenovirus receptor (CAR) in many primary cells limit the in vivo application. Liposome-complexed adenoviral vectors have proven to be useful for enhancing gene delivery in target cells that lack adenoviral receptors and avoiding a neutralizing antibody response. Here, we investigated antitumor effects of intravenous administration with PEG-PE cationic liposome-encapsulated recombinant human endostatin adenovirus (Ad-hEndo) on CAR-negative ovarian cancer. Electron micrography (EM) showed that these liposomes efficiently encapsulated the vectors, allowing CAR-independent adenovector transduction. The results showed that the complex enhanced transfection efficiency of recombinant adenovirus. Prolonged systemic administration was performed in immunocompetent mice and did not induce significant antibody response. The antitumor effect with PEG-PE cationic liposome encapsulated with Ad-hE (Ad-hE/lipo) was evaluated in the human ovarian cancer model. Systemic administration was well tolerated and resulted in marked suppression of tumor growth in an established ovarian cancer model, which was associated with a decreased number of micro-vessels and increased apoptosis of tumor cells. Our study shows that PEG-PE cationic liposome-encapsulated Ad-hE (Ad-hE/Lipo) can be administrated intravenously and lastingly to inhibit angiogenesis, thus showing promising clinical application.

A pilot study using nurse education as an intervention to increase skin self-examination for melanoma.

BACKGROUND: A pilot study of an intervention using nurse education for skin self-examination (SSE) was conducted in order to determine specific factors that would be important for the design of a larger intervention. METHODS: Seventy-five subjects completed a pretest, a posttest, a thorough skin examination by a dermatologist, and an educational session by a nurse. RESULTS: Results showed that the subjects increased the frequency of SSE to a predetermined optimal frequency of once every one to two months. Increases in optimal SSE were associated with increases in knowledge about melanoma (p = 0.006). CONCLUSIONS: Before intensive campaigns are launched to improve SSE, models incorporating theories of behavioral change should be tested.

No improvement in survival from melanoma diagnosed from 1973 to 1984.

BACKGROUND: While the incidence and mortality of melanoma has increased dramatically during the last few decades, survival rates, based on the case-fatality ratio, have apparently improved. Efforts at early detection have probably been effective in the discovery of lesions at a curable stage. However, the effects of lead-time bias need to be accounted for in order to understand the contribution of early detection to the increased incidence. This can best be done by appropriately controlling for depth of the tumour or a surrogate of depth, at diagnosis. METHODS: A survival analysis was conducted for 3197 Connecticut residents newly diagnosed with invasive melanoma between 1973 and 1984. Five prognostic variables were evaluated: sex, age at diagnosis, anatomical site, histological type, and year of diagnosis. RESULTS: As expected, women and the young had better survival than men and the elderly. Melanomas located on the trunk had poorer prognosis than those on other sites. The survival experience by histological type was significantly different; lentigo maligna melanoma and superficial spreading melanoma had the best survival and nodular melanomas the poorest, while 'other' and unclassifiable melanomas had intermediate survival. When survival by period of diagnosis was controlled by other variables, which included surrogates for disease stage, there was no improvement in survival over time. CONCLUSION: These data do not imply that early diagnosis and treatment are ineffective; rather, that within stages of disease, survival improvements did not occur during the period 1973-1984.