Rats Fed Diets with Different Energy Contribution from Fat Do Not Differ in Adiposity

ObjectiveTo determine whether rats reaching the same body mass, having been fed either a low-fat (LFD) or a high-fat diet (HFD), differ in white adipose tissue (WAT) deposition.MethodsIn experiment 1, 22 Sprague-Dawley rats of the same age were divided into 11 rats with body mass below the batch median and fed a HFD, and 11 above the median and fed a LFD. In experiment 2, 20 Sprague-Dawley rats of the same age and starting body mass were randomised to either a HFD or LFD. When all groups reached similar final body mass, WAT was quantified using magnetic resonance imaging (MRI), dissection, and plasma leptin.ResultsIn experiment 1, both groups reached similar final body mass at the same age; in experiment 2 the HFD group reached similar final body mass earlier than the LFD group. There were no significant differences in WAT as assessed by MRI or leptin between the HFD and LFD groups in both experiments. Dissection revealed a trend for higher retroperitoneal and epididymal adiposity in the HFD groups in both experiments.ConclusionsWe conclude that at similar body mass, adiposity is independent of the macronutrient composition of the feeding regimen used to achieve it.Key Words: High-fat diet, Low-fat diet, MRI, Leptin     

Pathological findings in 377 patients with differentiated thyroid cancer in a single centre

Aim-Background

The purpose of this study is to review the pathology findings of 377 patients diagnosed with differentiated thyroid cancer (DTC) in a single centre over a period of six years.

Methods

Retrospective review of all total and near-total thyroidectomies (TT and NTT) performed in a single institution. Clinical records were accessed for patient demographic data and clinical characteristics. Patients with a histopathologic diagnosis of DTC were grouped in incidental DTC and non-incidental DTC groups and TNM staging was used.

Results

1465 thyroidectomies were included. The M:F ratio was 1:2.9. 377/1465 patients had a histologic diagnosis of DTC (26%). T1b group (n=227) had a statistically significant higher number of cases, where tumor invaded the capsule, tumor extending extrathyroidally, tumor invading the blood vessels compared to T1a group (n=64) (p=0.001 for all three variables). T1a group had a statistically significant higher number of papillary conventional variant of DTC and more unifocal tumors (p=0.045 and p=0.004 respectively). In the non-incidental DTC group (n=79), there were 29 patients (37%) in T1a category and 16 of them had a unifocal papillary DTC.

Conclusions

16/79 of patients (20%) operated for DTC had a subcetrimetric, unifocal papillary DTC. According to the 2106 American Thyroid Association (ATA) Management Guidelines, these patients could potentially have been treated with a lobectomy alone. Patients in T1b category present more aggressive histologic features and should undergo multi-disciplinary team discussion to decide optimal surgical treatment.

     

Minimal social network effects evident in cancer screening behavior

BACKGROUND:

Social networks may influence screening behaviors. We assessed whether screening for breast, prostate, or colorectal cancer is influenced by the actual screening behaviors of siblings, friends, spouses, and coworkers.

METHODS:

We conducted an observational study using Framingham Heart Study data to assess screening for eligible individuals during the late 1990s. We used logistic regression to determine whether the probability of screening for breast, prostate, or colorectal cancer was influenced by the proportion of siblings, friends, and coworkers who had the same screening, as well as spouse's screening for colorectal cancer, adjusting for other factors that might influence screening rates.

RESULTS:

Among 1660 women aged 41‐70 years, 71.7% reported mammography in the previous year; among 1217 men aged 51‐70 years, 43.3% reported prostate‐specific antigen testing in the previous year; and among 1426 men and women aged 51‐80 years, 46.9% reported stool blood testing and/or sigmoidoscopy in the previous year. An increasing proportion of sisters who had mammography in the previous year was associated with mammography screening in the ego (odds ratio [OR], 1.034; 95% confidence interval [CI], 1.000‐1.065 for each 10% increase). A spouse with recent screening was associated with more colorectal cancer screening (OR, 1.65; 95% CI, 1.39‐1.98 vs unmarried). Otherwise, screening behaviors of siblings, friends, and coworkers were not associated with screening in the ego.

CONCLUSIONS:

Aside from a slight increase in breast cancer screening among women whose sisters were screened and colorectal cancer screening if spouses were screened, the screening behavior of siblings, friends, or coworkers did not influence cancer screening behaviors. Cancer 2011. © 2011 American Cancer Society.     

Longitudinal analysis of large social networks: estimating the effect of health traits on changes in friendship ties

We develop novel mixed effects models to examine the role of health traits on the status of peoples' close friendship nominations in the Framingham Heart Study. The health traits considered are both mutable (body mass index (BMI), smoking, blood pressure, body proportion, muscularity, and depression) and, for comparison, basically immutable (height, birth order, personality type, only child, and handedness); and the traits have varying degrees of observability. We test the hypotheses that existing ties (i.e. close friendship nominations) are more likely to dissolve between people with dissimilar (mutable and observable) health traits whereas new ties are more likely to form between those with similar (mutable and observable) traits while controlling for persons' age, gender, geographic separation, and education. The mixed effects models contain random effects for both the nominator (ego) and nominated (alter) persons in a tie to account for the fact that people were involved in multiple relationships and contributed observations at multiple exams. Results for BMI support the hypotheses that people of similar BMI are less likely to dissolve existing ties and more likely to form ties, while smoker to non-smoker ties were the least likely to dissolve and smoker to smoker ties were the most likely to form. We also validated previously known findings regarding homophily on age and gender, and found evidence that homophily also depends upon geographic separation.     

Racial disparity in hospice use in the United States in 2002

We used complete Centers for Disease Control death certificate records and the Centers for Medicare and Medicaid Services 100% Standard Analytic File for hospice claims for 2002 to examine differences in hospice utilization between African-American and white decedents living in the United States. White decedents were more likely to use hospice in the year before their death than African-American decedents (29% vs 22%). Cause-specific hospice utilization rates among women were consistently higher than among men within a given race. African-American decedents were consistently less likely to use hospice than white decedents for almost all conditions. Hospice utilization was lower among African-American than among white decedents in 31 of 40 states. The higher the overall hospice utilization in a state, the less the positive difference between white and African-American usage rates; that is, the more accepted hospice is, as measured by 'market share', the lower the racial disparity in its use.