Citations

The importance of portal insulin delivery in the regulation of postprandial carbohydrate metabolism is uncertain. To address this question, three groups of dogs were studied: one group in which pancreatic venous drainage was transected and reanastomosed (portal insulin delivery), one in which the pancreatic drainage was transected and anastomosed to the inferior vena cava (peripheral insulin delivery), and one that received only a sham operation. Plasma insulin was greater (P < 0.05) during peripheral insulin delivery than in either the portal or sham groups, respectively, before and after meal ingestion. On the other hand, C-peptide concentrations did not differ between groups, resulting in a higher (P < 0.001) insulin to C-peptide ratio in the peripheral group. This indicated that the hyperinsulinemia in the peripheral group was due to decreased insulin clearance rather than increased insulin secretion. Isotopically determined splanchnic uptake of ingested glucose, postprandial suppression of hepatic glucose release, incorporation of CO2 into glucose (a qualitative measure of gluconeogenesis), and total-body glucose uptake were virtually identical in all groups. Similarly, plasma lipid, β-hydroxybutyrate, and lactate concentrations did not differ between groups. Our data indicate that, despite differences in systemic insulin concentration, portal and peripheral insulin delivery comparably regulate hepatic and extrahepatic carbohydrate metabolism after meal ingestion.

Background— Among patients with severe aortic stenosis (AS) and preserved ejection fraction, those with low gradient (LG) and reduced stroke volume may have an adverse prognosis. We investigated the prognostic impact of stroke volume using the recently proposed flow-gradient classification. Methods and Results— We examined 1704 consecutive patients with severe AS (aortic valve area <1.0 cm 2 ) and preserved ejection fraction (≥50%) using 2-dimensional and Doppler echocardiography. Patients were stratified by stroke volume index (<35 mL/m 2 [low flow, LF] versus ≥35 mL/m 2 [normal flow, NF]) and aortic gradient (<40 mm Hg [LG] versus ≥40 mm Hg [high gradient, HG]) into 4 groups: NF/HG, NF/LG, LF/HG, and LF/LG. NF/LG (n=352, 21%), was associated with favorable survival with medical management (2-year estimate, 82% versus 67% in NF/HG; P <0.0001). LF/LG severe AS (n=53, 3%) was characterized by lower ejection fraction, more prevalent atrial fibrillation and heart failure, reduced arterial compliance, and reduced survival (2-year estimate, 60% versus 82% in NF/HG; P <0.001). In multivariable analysis, the LF/LG pattern was the strongest predictor of mortality (hazard ratio, 3.26; 95% confidence interval, 1.71–6.22; P <0.001 versus NF/LG). Aortic valve replacement was associated with a 69% mortality reduction (hazard ratio, 0.31; 95% confidence interval, 0.25–0.39; P <0.0001) in LF/LG and NF/HG, with no survival benefit associated with aortic valve replacement in NF/LG and LF/HG. Conclusions— NF/LG severe AS with preserved ejection fraction exhibits favorable survival with medical management, and the impact of aortic valve replacement on survival was neutral. LF/LG severe AS is characterized by a high prevalence of atrial fibrillation, heart failure, and reduced survival, and aortic valve replacement was associated with improved survival. These findings have implications for the evaluation and subsequent management of AS severity.

We analyzed the phenotype associated with the atrial natriuretic peptide (ANP) genetic variant rs5065 in a random community-based sample. We also assessed and compared the biological action of 2 concentrations (10 −10 mol/L, 10 –8 mol/L) of ANP and ANP-RR, the protein variant encoded by the minor allele of rs5065, on activation of the guanylyl cyclase (GC)-A and GC-B receptors, production of the second messenger 3′,5′-cGMP in endothelial cells, and endothelial permeability. rs5065 genotypes were determined in a cross-sectional adult cohort from Olmsted County, MN (n=1623). Genotype frequencies for rs5065 were 75%, 24%, and 1% for TT, TC, and CC, respectively. Multivariate analysis showed that the C allele was associated with increased risk of cerebrovascular accident (hazard ratio, 1.43; 95% confidence interval, 1.09–1.86; P =0.009) and higher prevalence of myocardial infarction (odds ratio, 1.82; 95% confidence interval, 1.07–3.09; P =0.026). ANP-RR 10 −8 mol/L activated the GC-A receptor (83.07±8.31 versus no treatment 0.18±0.04 per 6 wells; P =0.006), whereas ANP-RR 10 −10 mol/L did not. Neither 10 −8 mol/L nor 10 −10 mol/L ANP-RR activated GC-B receptor ( P =0.10, P =0.35). ANP 10 −8 mol/L and ANP-RR 10 −8 mol/L stimulated 3′,5′-cGMP production in endothelial cells similarly ( P =0.58). Both concentrations of ANP-RR significantly enhanced human aortic endothelial cell permeability (69 versus 29 relative fluorescence units [RFUs], P =0.012; 58 versus 39 RFUs, P =0.015) compared with ANP. The minor allele of rs5065 was associated with increased cardiovascular risk. ANP-RR activated the GC-A receptor, increased 3′,5′-cGMP in endothelial cells, and when compared with ANP, augmented endothelial cell permeability.

Background and Purpose— Meta-analyses of extant genome-wide data illustrate the need to focus on subtypes of ischemic stroke for gene discovery. The National Institute of Neurological Disorders and Stroke SiGN (Stroke Genetics Network) contributes substantially to meta-analyses that focus on specific subtypes of stroke. Methods— The National Institute of Neurological Disorders and Stroke SiGN includes ischemic stroke cases from 24 genetic research centers: 13 from the United States and 11 from Europe. Investigators harmonize ischemic stroke phenotyping using the Web-based causative classification of stroke system, with data entered by trained and certified adjudicators at participating genetic research centers. Through the Center for Inherited Diseases Research, the Network plans to genotype 10 296 carefully phenotyped stroke cases using genome-wide single nucleotide polymorphism arrays and adds to these another 4253 previously genotyped cases, for a total of 14 549 cases. To maximize power for subtype analyses, the study allocates genotyping resources almost exclusively to cases. Publicly available studies provide most of the control genotypes. Center for Inherited Diseases Research–generated genotypes and corresponding phenotypes will be shared with the scientific community through the US National Center for Biotechnology Information database of Genotypes and Phenotypes, and brain MRI studies will be centrally archived. Conclusions— The Stroke Genetics Network, with its emphasis on careful and standardized phenotyping of ischemic stroke and stroke subtypes, provides an unprecedented opportunity to uncover genetic determinants of ischemic stroke.

Synovial cysts of the temporomandibular joint are rare, and to our knowledge, only 14 cases have been reported. The most common presentation is local pain and swelling. We present a case of a synovial cyst presenting with neuralgia in the distribution of the auriculotemporal nerve, initially misdiagnosed as trigeminal neuralgia.

Abstract Labral repair has become an essential technique in the arthroscopic surgical management of femoroacetabular impingement. Several clinical studies suggest that labral repair results in superior patient outcomes in comparison to labral debridement alone. The repair procedure requires accurate evaluation of labral tissue quality, precise placement of sutures and anchors, and careful re‐tensioning of the labrum. We present our preferred technique for labral repair. Technique Video video See video under supplementary data.

BACKGROUNDDrug choice and delivered dose of treatment potentially influence outcome in patients treated for follicular lymphoma (FL). Historically, observational studies have evaluated drug choice. The National LymphoCare Study (NLCS) is a prospective, observational study of patients with FL who were enrolled at academic and community practice sites in the United States between 2004 and 2007. In the current study, the authors report on measures of delivered dose and its impact on outcomes for the most common first‐line regimens.METHODSAll evaluable patients with FL who were treated with initial rituximab plus cyclophosphamide, doxorubicin, vincristine, and prednisone (R‐CHOP); rituximab plus cyclophosphamide, vincristine, and prednisone (R‐CVP); or rituximab plus a fludarabine‐containing regimen (R‐Flu) were included. Associations between baseline factors, choice of treatment, number of cycles received, completion of therapy, and patient outcomes were assessed.RESULTSA total of 646 patients received R‐CHOP, 297 received R‐CVP, and 222 received R‐Flu. Characteristics were similar between the 3 groups with the following exceptions. Patients receiving R‐CHOP were more often found to have grade 3 FL and patients receiving R‐CVP were older and had higher Follicular Lymphoma International Prognostic Index scores. The majority of patients (80%) received ≥ 5 cycles of treatment. Toxicity, but not disease progression, was commonly cited as the reason for the early discontinuation of treatment (51% vs 6%). Time to retreatment was shorter for patients receiving ≤ 4 cycles, regardless of the treatment regimen used. The number of cycles was associated with overall survival, progression‐free survival, and lymphoma‐related mortality for patients receiving R‐CVP.CONCLUSIONSThe majority of patients with FL receiving chemoimmunotherapy in the NLCS completed ≥ 5 cycles of treatment. Strategies to improve dose delivery appear unlikely to impact outcomes, except possibly in patients receiving R‐CVP. Although early treatment discontinuation appears to be associated with survival, this analysis does not implicate causality. Cancer 2013;119:4129–4136. © 2013 American Cancer Society.

Objective Although robotic technology has addressed many of the limitations of traditional videoscopic surgery, robotic surgery has not gained widespread acceptance in the general thoracic community. We report our initial robotic surgery experience and propose a structured, competency-based pathway for the development of robotic skills. Methods Between December 2008 and February 2012, a total of 79 robot-assisted pulmonary, mediastinal, benign esophageal, or diaphragmatic procedures were performed. Data on patient characteristics and perioperative outcomes were retrospectively collected and analyzed. During the study period, one surgeon and three residents participated in a triphasic, competency-based pathway designed to teach robotic skills. The pathway consisted of individual preclinical learning followed by mentored preclinical exercises and progressive clinical responsibility. Results The robot-assisted procedures performed included lung resection (n = 38), mediastinal mass resection (n = 19), hiatal or para-esophageal hernia repair (n = 12), and Heller myotomy (n = 7), among others (n = 3). There were no perioperative mortalities, with a 20% complication rate and a 3% readmission rate. Conversion to a thoracoscopic or open approach was required in eight pulmonary resections to facilitate dissection (six) or to control hemorrhage (two). Fewer major perioperative complications were observed in the later half of the experience. All residents who participated in the thoracic surgery robotic pathway perform robot-assisted procedures as part of their clinical practice. Conclusions Robot-assisted thoracic surgery can be safely learned when skill acquisition is guided by a structured, competency-based pathway.