Facilitated long chain fatty acid uptake by adipocytes remains upregulated relative to BMI for more than a year after major bariatric surgical weight loss.

OBJECTIVE: This study examined whether changes in adipocyte long chain fatty acid (LCFA) uptake kinetics explain the weight regain increasingly observed following bariatric surgery. METHODS: Three groups (10 patients each) were studied: patients without obesity (NO: BMI 24.2 ± 2.3 kg m(-2) ); patients with obesity (O: BMI 49.8 ± 11.9); and patients classified as super-obese (SO: BMI 62.6 ± 2.8). NO patients underwent omental and subcutaneous fat biopsies during clinically indicated abdominal surgeries; O were biopsied during bariatric surgery, and SO during both a sleeve gastrectomy and at another bariatric operation 16 ± 2 months later, after losing 113 ± 13 lbs. Adipocyte sizes and [(3) H]-LCFA uptake kinetics were determined in all biopsies. RESULTS: Vmax for facilitated LCFA uptake by omental adipocytes increased exponentially from 5.1 ± 0.95 to 21.3 ± 3.20 to 68.7 ± 9.45 pmol/sec/50,000 cells in NO, O, and SO patients, respectively, correlating with BMI (r = 0.99, P < 0.001). Subcutaneous results were virtually identical. By the second operation, the mean BMI (SO patients) fell significantly (P < 0.01) to 44.4 ± 2.4 kg m(-2) , similar to the O group. However, Vmax (40.6 ± 11.5) in this weight-reduced group remained ~2X that predicted from the BMI:Vmax regression among NO, O, and SO patients. CONCLUSIONS: Facilitated adipocyte LCFA uptake remains significantly upregulated ≥1 year after bariatric surgery, possibly contributing to weight regain.

A multicenter study of initiation of antiretroviral therapy and transmitted drug resistance in antiretroviral-naive adolescents and young adults with HIV in New York City.

BACKGROUND: In December 2009, the Department of Health and Human Services guidelines for initiation of antiretroviral therapy (ART) changed to include patients with CD4 counts between 350 and 500 cells/µL. The aims of this study were to assess uptake of this recommendation in ART-naive youth with human immunodeficiency virus (HIV) and to describe the epidemiology of transmitted genotypic drug resistance mutations (DRMs) in this population. METHODS: A multicenter, retrospective cohort study of ART initiation in ART-naive youth was performed. Eligible subjects were 13-25 years of age, were diagnosed with HIV within 1 year of presentation to care at the study sites, and presented to care from January 2007 to June 2011. RESULTS: Of 685 potential subjects identified, 331 (49%) fulfilled inclusion criteria. Mean CD4 count at presentation to care was 452 cells/µL. Overall, 191 (58%) subjects started ART. The mean CD4 count at ART initiation was 261 cells/µL before and 363 cells/µL after the 2009 guideline change (P < .0001). Of 212 (64%) subjects with resistance testing available prior to ART initiation, 38 (18%) subjects had a major DRM and an increased proportion of resistance was seen in later study years. CONCLUSIONS: Our study demonstrated an uptake in recently changed guideline recommendations to treat HIV-infected individuals at higher CD4 counts and reinforces the importance of performing resistance testing at entry into care, as 18% of our population had major DRMs prior to initiation of ART.