Insulin-like growth factor binding protein 2 null mice (Igfbp2-/-) are protected against trabecular bone loss after vertical sleeve gastrectomy

BACKGROUND

Bariatric surgery has been shown to result in weight loss, improved hemoglobin A1C, and decreased mortality but can also lead to bone loss and increased fracture rates. Serum IGFBP-2 is elevated in patients after bariatric surgery and although it may lead to improved blood glucose, may also drive bone resorption, and inhibit IGF-I action. This study tested the hypothesis that Igfbp2-/- mice were acutely protected from bone loss after vertical sleeve gastrectomy (VSG).

METHODS

Thirty-four mice, 17 Igfbp2-/- and 17 + / + underwent a hand-sewn VSG or sham surgery, at 16 weeks of age. Mice were harvested at 20 weeks of age. DXA was measured for body composition, areal bone mineral density (aBMD), areal bone mineral content (aBMC), femoral bone mineral density (fBMD), and femoral bone mineral content (fBMC) at 15, 18, and 20 weeks of age. Micro-computed tomography and serum ELISA assays were measured and analyzed at 20 weeks of age.

RESULTS

Both Igfbp2-/- and + / + mice lost significant weight (P = 0.0251, P = 0.0003, respectively) and total fat mass (P = 0.0082, P = 0.0004, respectively) at 4 weeks after VSG. Igfbp2+/+ mice lost significant aBMD, fBMD, fBMC, trabecular BMD, trabecular BV/TV and cortical tissue mineral density (P = 0.0150, P = 0.0313, P = 0.0190, P = 0.0072, and 0.0320 respectively). The Igfbp2-/- mice did not show significant bone loss in these parameters nor in trabecular BV/TV. Both Igfbp2-/- and + / + mice had less cortical bone area (P = 0.0181, P =  < .00001), cortical area over total area (P = 0.0085, P = 0.0007), and cortical thickness (P = 0.0050, P =  < 0.0001), respectively. Igfbp2+/+ mice demonstrated significantly lower polar, minimum, and maximum moments of inertia (P = 0.0031, P = 0.0239, and P = 0.0037, respectively). Igfbp2+/+ had significantly higher levels of IGFBP-2 at 2 weeks postoperatively after VSG (P = 0.035), and elevated levels of CTx and P1NP (P = 0.0127, P = 0.0058, respectively).

CONCLUSIONS

Igfbp2-/- mice were protected against trabecular bone loss and had attenuated cortical bone loss 4 weeks after VSG.

Don't Shoot the Messenger: Surgical Programs Can Do More to Keep Applicants Informed

OBJECTIVE

The interview process for applying to general surgery residency is burdened by a high volume of applicants, resulting in unprofessional behavior by both applicants and programs. Sharing more information regarding interview scheduling with applicants may limit fourth year medical student educational disruptions, minimized late cancellations to interview, and improve overall satisfaction with the process. Thus, we set out to determine what information is currently available to applicants.

DESIGN

We used publicly accessible sources to determine what information was shared by US general surgery residency programs with applicants. Specifically, we looked at the deadline for applications, United States Medical Licensing Examination Step 1 and 2 score cutoffs, number of interview dates available, specific interview dates, a stated policy to not offering more interviews than slots, dates when applicants can expect to be notified of interview offers, notification of decision to decline, and International Medical Graduate and visa policies.

SETTING

This study took place at Maine Medical Center in Portland, Maine, an academic medical center with a general surgery residency program.

PARTICIPANTS

Not applicable.

RESULTS

Three hundred seventeen programs were examined. Seventy-six percent of programs specified an application deadline, 65% of programs specified a Step 1 cut-off score, 50% of programs specified a Step 2 cut-off score, 61% of programs stated a visa policy, and 50% of programs stated an International Medical Graduate policy. Twenty-five percent of programs disclosed the number of interview dates, 23% disclosed what those interview dates were. About 3.4% of programs gave interview release dates, 2.8% of programs notify applicants of decline to interview, and 0.63% of programs explicitly describe a policy of offering only as many interviews as slots available. Thirty-two percent of programs provided conflicting information.

CONCLUSIONS

The information available to applicants from public access sources regarding interview scheduling is minimal, unstandardized, and unreliable. Notably lacking were policies that only offer as many interviews as slots available, dates when applicants can expect to be notified of interview offers, and notification of declines. Providing such information to applicants in a standardized way may improve satisfaction with the interview scheduling process.