Transition to Practice: A Global Surgery Approach.

OBJECTIVE: To determine the feasibility of a global surgery setting for a transition to practice experience. SETTING: A rural hospital in Malawi, Africa. PARTICIPANTS: A recent graduate of a U.S. general surgery residency program. RESULTS: Fellow performed 305 cases across the surgical disciplines with demonstrated improvements in operative ability. CONCLUSION: The global surgery approach to transition to practice offers a unique opportunity to complement domestic training while providing critical assistance to communities with few surgical providers.

Surgical volunteerism as a collaborative teaching activity can benefit surgical residents in low-middle income countries.

Surgical care is desperately needed in low-middle income countries (LMIC). Due to small numbers of faculty in local training programs, residents have limited exposure to subspecialists. We describe a teaching activity between visiting surgeons from the U.S. and a residency program in Malawi as an example for how surgeons in high income countries can meaningfully contribute. A short-term education activity was developed where residents participated in a pre-test on pediatric surgical management, lectures, intra-operative instruction, bedside rounds and a post-test. Five residents participated and all intend to practice in sub-Saharan Africa. All residents improved their scores from the pre-test to post-test (mean 44%-91%). The residency program performs approximately 1200 major surgical cases and 800 minor surgical procedures each year, representing a broad range of general surgery. Additionally, the residents encounter a broad range of pathology. Short-term mentorship activities in partnership with an established training program can enhance surgical resident education in LMIC, particularly for subspecialty care.

Loma Linda Global Surgery Elective: First 1000 Cases.

OBJECTIVE: To determine the nature and volume of surgical cases being performed by US general surgery residents during a global surgery elective. DESIGN: Retrospective review of case logs from 2012 to 2016. SETTING: Malamulo Mission Hospital is a rural hospital in southern Malawi. PARTICIPANTS: Rotating residents from a US-based general surgery residency program. RESULTS: Residents performed 12 cases per week from a variety of surgical disciplines. CONCLUSION: Global surgery rotations with dedicated faculty can provide excellent surgical variety and volume to enhance the training of residents.

Expression and actions of HIF prolyl-4-hydroxylase in the rat kidneys.

Hypoxia inducible factor (HIF) prolyl-4-hydroxylase domain-containing proteins (PHDs) promote the degradation of HIF-1alpha. Because HIF-1alpha is highly expressed in the renal medulla and HIF-1alpha-targeted genes such as nitric oxide synthase, cyclooxygenase, and heme oxygenase are important in the regulation of renal medullary function, we hypothesized that PHD regulates HIF-1alpha levels in the renal medulla and, thereby, participates in the control of renal Na(+) excretion. Using real-time RT-PCR, Western blot, and immunohistochemical analyses, we have demonstrated that all three isoforms of PHD, PHD1, PHD2, and PHD3, are expressed in the kidneys and that PHD2 is the most abundant isoform. Regionally, all PHDs exhibited much higher levels in renal medulla than cortex. A furosemide-induced increase in renal medullary tissue Po(2) significantly decreased PHD levels in renal medulla, whereas hypoxia significantly increased mRNA levels of PHDs in cultured renal medullary interstitial cells, indicating that O(2) regulates PHDs. Functionally, the PHD inhibitor l-mimosine (l-Mim, 50 mg x kg(-1) x day(-1) i.p. for 2 wk) substantially upregulated HIF-1alpha expression in the kidneys, especially in the renal medulla, and remarkably enhanced (by >80%) the natriuretic response to renal perfusion pressure in Sprague-Dawley rats. Inhibition of HIF transcriptional activity by renal medullary transfection of HIF-1alpha decoy oligodeoxynucleotides attenuated l-Mim-induced enhancement of pressure natriuresis, which confirmed that HIF-1alpha mediated the effect of l-Mim. These results indicate that highly expressed PHDs in the renal medulla make an important contribution to the control of renal Na(+) excretion through regulation of HIF-1alpha and its targeted genes.

Role of renal medullary heme oxygenase in the regulation of pressure natriuresis and arterial blood pressure.

Recent studies have demonstrated that inhibition of renal medullary heme oxygenase (HO) activity and carbon monoxide (CO) significantly decreases renal medullary blood flow and sodium excretion. Given the crucial role of renal medullary blood flow in the control of pressure natriuresis, the present study was designed to determine whether renal medullary HO activity and resulting CO production participate in the regulation of pressure natriuresis and thereby the long-term control of arterial blood pressure. In anesthetized Sprague-Dawley rats, increases in renal perfusion pressure induced significant elevations of CO concentrations in the renal medulla. Renal medullary infusion of chromium mesoporphyrin (CrMP), an inhibitor of HO activity, remarkably inhibited HO activity and the renal perfusion pressure-dependent increases in CO levels in the renal medulla and significantly blunted pressure natriuresis. In conscious Sprague-Dawley rats, continuous infusion of CrMP into the renal medulla significantly increased mean arterial pressure (129+/-2.5 mm Hg in CrMP group versus 118+/-1.6 mm Hg in vehicle group) when animals were fed a normal salt diet (1% NaCl). After rats were switched to a high-salt diet (8% NaCl) for 10 days, CrMP-treated animals exhibited further increases in mean arterial pressure compared with CrMP-treated animals that were kept on normal salt diet (152+/-4.1 versus 130+/-4.2 mm Hg). These results suggest that renal medullary HO activity plays a crucial role in the control of pressure natriuresis and arterial blood pressure and that impairment of this HO/CO-mediated antihypertensive mechanism in the renal medulla may result in the development of hypertension.