Acyl chain length, saturation, and hydrophobicity modulate the efficiency of dietary fatty acid absorption in adult humans.

Intestinal fat absorption is known to be, overall, a highly efficient process, but much less is known about the efficiency with which individual dietary fatty acids (FA) are absorbed by the adult small intestine. We therefore measured the absorption efficiency of the major dietary FA using sucrose polybehenate (SPB) as a nonabsorbable marker and analyzed how it is modulated by acyl chain physicochemical properties and polymorphisms of proteins involved in chylomicron assembly. Dietary FA absorption efficiency was measured in 44 healthy subjects fed a standard diet containing 35% fat and 5% SPB. FA and behenic acid (BA) were measured in homogenized diets and stool samples by gas chromatography-mass spectroscopy, and coefficients of absorption for each FA were calculated as 1 - [(FA/BA)feces/(FA/BA)diet]. Absorption coefficients for saturated FA decreased with increasing chain length and hydrophobicity (mean ± SE) and ranged from 0.95 ± 0.02 for myristate (14:0), 0.80 ± 0.03 for stearate (18:0), to 0.26 ± 0.02 for arachidate (20:0). Absorption coefficients for unsaturated FA increased with increasing desaturation from 0.79 ± 0.03 for elaidic acid (18:1t), 0.96 ± 0.01 for linoleate (18:2), to near complete absorption for eicosapentaenoic (20:5) and docosahexaenoic (22:6) acids. Of several common genetic polymorphisms in key proteins involved in the chylomicron assembly pathway, only the intestinal fatty acid-binding protein-2 A54T allele (rs1799883) had any impact on FA absorption. We conclude that acyl chain length, saturation, and hydrophobicity are the major determinants of the efficiency with which dietary FA are absorbed by the adult small intestine.

Intentional foreign object ingestions: need for endoscopy and surgery.

BACKGROUND: Intentional ingestion of foreign objects (IIFO) is common in the incarcerated population. This study was undertaken in order to better define clinical patterns of IIFO among prisoners. We sought to determine factors associated with the need for endoscopic and surgical therapy for IIFO. METHODS: After obtaining permission to conduct IIFO research in incarcerated populations, study patients were identified by ICD-9 codes. Patient charts were reviewed for demographics; past medical history; IIFO characteristics; and diagnostic, endoscopic, and surgical findings. Univariate and multivariate analyses were performed using statistical software. RESULTS: Thirty patients with 141 episodes of IIFO were identified. The mean number of ingested items per episode was 4.60. Endoscopy was performed in 97 of 141 IIFO instances, with failure to retrieve the ingested object in 21 of 97 cases (22%). Eleven instances (7.8%) required surgical intervention. On multivariate analyses, hospital admission was associated with elevated white blood cell count (odds ratio [OR] 1.4, P < 0.05) and number of items ingested (OR 1.3, P < 0.05). The need for endoscopy was independently associated with ingestion of multiple objects (OR 3.3, P < 0.05) and elevated white blood cell count (OR 1.3, P < 0.05). Surgical therapy was significantly associated with elevated white blood cell count (OR 1.6, P < 0.01) and with increasing number of ingested items (OR 1.07 per item, P < 0.05). Endoscopy is associated with significantly lower odds of surgery (OR 0.13, P < 0.01). CONCLUSIONS: Intentional ingestion of foreign objects continues to pose a significant human and economic burden. The need for admission or therapy is frequently associated with leukocytosis. Further investigation is warranted into resource-appropriate triage of patients who present with IIFO.

Hepatic steatosis and subclinical cardiovascular disease in a cohort enriched for type 2 diabetes: the Diabetes Heart Study.

OBJECTIVES: To explore mechanisms whereby hepatic steatosis may be associated with cardiovascular risk, we investigated cross-sectional relationships between hepatic steatosis, regional fat accumulation, inflammatory biomarkers, and subclinical measures of atherosclerosis in the Diabetes Heart Study. METHODS: The Diabetes Heart Study is a family study of sibling pairs concordant for type 2 diabetes. A subset of 623 randomly selected participants was evaluated for hepatic steatosis, defined as a liver:spleen attenuation ratio of <1.0 by computed tomography. We quantified visceral fat, subcutaneous fat, coronary, aortic, and carotid artery calcium by computed tomography; and carotid atherosclerosis by ultrasound. Associations between the liver:spleen attenuation ratio and these factors were expressed as Spearman correlations. RESULTS: After adjustment for age, race, gender, body mass index, and diabetes status, the liver:spleen attenuation ratio correlated with visceral fat (r =-0.22, P < 0.0001) and subcutaneous fat (r =-0.13, P= 0.031). Hepatic steatosis was associated with lower high-density lipoprotein (r = 0.21, P < 0.0001), higher triglycerides (r =-0.25, P < 0.0001), higher C-reactive protein (r =-0.095, P= 0.004), and lower serum adiponectin (r = 0.34, P < 0.0001). There were no significant associations between the liver:spleen attenuation ratio and coronary, aortic, or carotid calcium, or carotid intimal thickness. CONCLUSIONS: This suggests that hepatic steatosis is less likely a direct mediator of cardiovascular disease and may best be described as an epiphenomenon. The strong correlations between pro-atherogenic biomarkers, visceral fat, and elements of the metabolic syndrome suggest that hepatic steatosis reflects more than general adiposity, but represents a systemic, inflammatory, pro-atherogenic adipose state.