Impact of Epithelial Claudin-4 and Leukotriene B4 Receptor 2 in Normoganglionic Hirschsprung Disease Colon on Post Pull-through Enterocolitis.

PURPOSE: To investigate whether Leukotriene B4 receptor 2 (BLT-2), an upstream regulator of tight junction protein (TJP) Claudin-4, and TJPs could be etiologic factors in Hirschsprung-associated enterocolitis (HAEC) after pull-through (PT) for Hirschsprung disease (HD). METHODS: Normoganglionic colon (HD-N) and aganglionic rectum (HD-A) specimens from rectal/rectosigmoid (R/RS) or descending/transverse (D/T) HD were assessed using quantitative polymerase chain reaction (qPCR) for Occludin, TJP-1, TJP-2, Junctional adhesion molecule (JAM)-1, JAM-2, Claudin-1, Claudin-3, Claudin-4, and BLT-2 and immunoblotting for Claudin-4 using fresh specimens obtained intraoperatively (2021-2024; n = 17; R/RS = 15 and D/T = 2). Claudin-4 immunohistochemistry was also evaluated quantitatively using preserved (n = 29; R/RS = 20 and D/T = 9; 2009-2021) and fresh HD specimens for comparison with anorectal malformation patients having colostomy closure as controls (n = 42) and between HD-A versus HD-N, R/RS versus D/T, and HAEC (+) versus HAEC (-). Technically inadequate or transitional zone PT were excluded. RESULTS: Subjects were 123 PT cases. Mean ages at PT/colostomy closure (years) were R/RS: 2.7 ± 2.9, D/T: 1.6 ± 2.2, and controls: 1.4 ± 0.7. Postoperative HAEC occurred 18 times in 14 PT cases (grade I = 5, grade II = 13). Post-PT HAEC was significantly more frequent in D/T (50.0% versus 6.4%; p < 0.001); Claudin-4 was significantly lower in HD-N from post-PT HAEC cases, especially D/T (p < 0.05) on immunohistochemistry. Claudin-4 was significantly lower in HD-N/HD-A compared with controls on immunoblotting (p < 0.05) and immunohistochemistry (p < 0.001). qPCR showed TJP-1, TJP-2, JAM-1, JAM-2, Claudin-4, and BLT-2 were significantly lower in HD-N/HD-A compared with controls. CONCLUSIONS: Lower Claudin-4 and BLT2 in post-PT HAEC HD-N (especially D/T) suggests generalized epithelial barrier derangement with possible etiologic implications for HAEC. LEVEL OF EVIDENCE: Ⅱ.

Questioning the Correlation Between Incidence of Hirschsprung Disease And Indications for Rectal Biopsy.

Aim: To review the indications for rectal mucosal/submucosal biopsy (RMSBx) used for diagnosing Hirschsprung's disease (HD) in pediatric patients. Methods: The medical records of all children between 1 and 15 years old assessed for chronic constipation between 2012 and 2022 were reviewed. Until the end of 2018, enema usage (E+) was a major indication for RMSBx. In 2019, laxative use for 3 months irrespective of enema use was added as an indication (L+). To determine the relevance of enema usage, L+ was subdivided by enema usage into (L+E+) and (L+E-) groups. The effect of changing the indications for RMSBx on the incidence of HD was investigated. Results: Of 562 eligible subjects, E+ = 410, L+ = 152; demographics are similar. RMSBx rate in E+ (E+RMSBx) was 36/410 (8.8%) and in L+ (L+RMSBx) was 42/152 (27.6%;) (P < .05). For L+RMSBx, 15/42 were L+E+ and 27/42 were L+E-. HD incidence in E+RMSBx was 8/36 (22.2%; E+HD) and in L+RMSBx was 13/42 (31.0%; L+HD) (p = ns). In L+RMSBx, HD incidence in L+E+ was 5/15 (33.3%; L+E+HD) and in L+E- was 8/27 (29.6%; L+E-HD) (P = ns). Differences in daily bowel motion frequency 6 months postoperatively were not statistically significant; E+HD (1.75/d) versus L+HD (2.03/d) and L+E+HD (1.60/day) versus L+E-HD (2.31/day). Unassisted voluntary defecation was confirmed 12 months postoperatively in 7/8 (87.5%) E+HD, 11/13 (84.6%) L+HD, 4/5 (80.0%) L+E+HD, and 7/8 (87.5%) L-E-HD; differences were not significant. Laxatives were still required in 2/8 (25.0%) E+HD, 3/13 (23.1%) L+HD, in 1/5 (20.0%) in L+E+HD, and 2/8 (25.0%) L+E-HD; differences were not significant. Conclusion: Incidence of HD was higher in L+HD, but not significantly different suggesting that indications for RMSBx have potential to influence incidence of HD and hint that the incidence of HD could actually be higher. Further assessment of additional indications is warranted to diagnose HD with greater accuracy.

Retroperitoneoscopic Simple Nondismembered Pyeloplasty with Da Vinci Si Assistance to Prevent Alignment Shift.

Aims: Retroperitoneoscopic simple nondismembered pyeloplasty (SNDP) with da Vinci Si assistance was developed because of a possible risk for alignment shift after retroperitoneoscopic diamond-shaped bypass pyeloplasty (Diamond-Bypass; DP). Outcomes of SNDP and DP were compared. Materials and Methods: For SNDP, a small longitudinal incision is made on the border of the dilated pelvis and narrowed ureter at the ureteropelvic junction (UPJ). Extending this incision toward the pelvis allows identification of mucosa while maintaining the integrity of surrounding tissues that are so thin and fragile that they will not influence lumen alignment. Data for DP were obtained from a previously published article. Results: For SNDP (n = 3), mean age at surgery was 2.67 years (range: 1-4), mean operative time was 176 minutes. Mean postoperative Society of Fetal Urology (SFU) grades for hydronephrosis were 1.2, 0.7, and 0.6, 1, 2, and 3 months after stent removal, respectively. Postoperative diethylenetriaminepentaacetic acid (DTPA) was normal (n = 3). For DP (n = 5) mean age at surgery was 4.3 years (range: 1-14), mean operative time was 189 minutes. Mean postoperative SFU grades were 2.8, 2.2, and 1.6, respectively. Postoperative DTPA was normal (n = 4) and delayed (n = 1). All SNDP and DP were asymptomatic by 3 months after stent removal. Conclusion: Both SNDP and DP have favorable outcomes. If the UPJ is located at the lowest end of the renal pelvis, SNDP may improve hydronephrosis more quickly.

The outcome of closure of inguinal hernia with laparoscopic percutaneous extraperitoneal closure in young adults.

BACKGROUND: Hernioplasty is one of the most commonly performed surgeries. However, the optimal procedure for young adults has not been defined yet. Our study compared the outcomes of laparoscopic percutaneous extraperitoneal closure (LPEC) in young adults with outcomes in children. MATERIAL AND METHODS: We retrospectively reviewed patients aged 0-30 years who underwent LPEC. Data regarding age, sex, hernia type, surgical time, pre-intraoperative laterality, contralateral patent processus vaginalis (CPPV), and complications were analyzed. RESULTS: LPEC was performed on 2642 patients in our hospital. Of these, 51 patients were young adults (aged 15-30 years). Asymptomatic CPPV in unilateral patients was frequent in the <15-year age group (50.2%) compared to the 15-30-year age group (15.9%). The median surgical time was shorter in the <15-year age group (19 min, interquartile range [IQR]: 24-33) compared to that of the 15-30-year age group (33 min, IQR: 23.3-40.8). CONCLUSIONS: This is the first report on the outcomes in young adult patients who underwent LPEC. The median surgical time was longer in the 15-30-year age group than in the <15-year age group. The median follow-up was 4.7 years with no intra-postoperative complications, such as postoperative bleeding, infection, persistent pain, and recurrence. LPEC is an effective, cosmetic, and safe surgical treatment in young adults and children.

Comparative assessment of fully laparoscopic Duhamel-Z with minimal rectorectal dissection vs. laparoscopy-assisted Duhamel-Z with blunt manual rectorectal dissection for total colonic aganglionosis.

Aims: Early postoperative outcome (EPO) was compared between fully laparoscopic Duhamel-Z (F-Dz) and laparoscopy-assisted Duhamel-Z (A-Dz) anastomoses performed for total colonic aganglionosis (TCA). Methods: EPO was assessed quarterly for the first year after F-Dz/A-Dz using a continence evaluation score (CES) based on stool frequency (motions/day) and stool consistency (0 = liquid, 1 = soft, 2 = formed), presence of anal erosion (0 = severe, 1 = moderate, 2 = mild), and incidence of enterocolitis.Surgical technique involved taking the ileostomy down, dissecting the colon laparoscopically, and preparing the pull-through ileum through the stoma wound. In F-Dz (n = 3), a working port (SILS trocar) was inserted, and laparoscopic retrorectal dissection with forceps used to create a retrorectal tunnel from the peritoneal reflection extending downward as narrow as possible along the posterior wall of the rectum to prevent lateral nerve injury and preserve vascularity. After completing the tunnel, the ileum was pulled-through from an incision on the anorectal line and a Z-shaped ileorectal side-to-side anastomosis performed without a blind pouch. In A-Dz (n = 11), the retrorectal pull-through route was created through a Pfannenstiel incision using blunt manual (finger) dissection along the anterior surface of the sacrum. Results: Subject backgrounds were similar. Mean quarterly data were: frequency (F-Dz: 4.67, 4.67, 4.67, 3.33) vs. (A-Dz: 7.27, 7.09, 6.18, 5.36) p < .05; consistency (F-Dz: 0.33, 0.67, 0.67, 0.67) vs. (A-Dz: 0.27, 0.45, 0.70, 0.73) p = ns; anal erosion (F-Dz: 0.33, 0.33, 0.33, 0.67) vs. (A-Dz: 0.18, 0.36, 0.45, 0.64) p = ns; and enterocolitis (F-Dz: 1 episode in 1/3 cases or 33.3%) vs. (A-Dz: 7 episodes in 6/11 cases or 54.5%) p = ns. Conclusions: Overall, EPO after F-Dz was better than after A-Dz.

Remote cadaveric minimally invasive surgical training.

Objective: The aim of the study is to discuss the efficacy of live vs. remote cadaver surgical training (CST) for minimally invasive surgery (MIS). Methods: A cohort of 30 interns in their first and second years of training were divided into three groups: live observers (n = 12), live participants (n = 6), and remote observers: (n = 12). The interns had the opportunity to either observe or actively participate in two different surgical procedures, namely, laparoscopic lower anterior resection, performed by a colorectal surgical team, and laparoscopic fundoplication, performed by a pediatric surgical team. The procedures were conducted either at a base center or at a remote center affiliated with the institute. Some of the interns interacted directly with the surgical teams at the base center, and others interacted indirectly with the surgical teams from the remote center. All interns were administered questionnaires before and after completion of the CST in order to assess their understanding of various aspects related to the operating room layout/instruments (called "design"), accessing the surgical field (called "field"), understanding of anatomic relations (called "anatomy"), their skill of dissection (called "dissection"), ability to resolve procedural/technical problems (called "troubleshooting"), and their skill in planning surgery (called "planning") according to their confidence to operate using the following scale: 1 = not confident to operate independently; 4 = confident to operate with a more senior trainee; 7 = confident to operate with a peer; and 10 = confident to operate with a less experienced trainee. A p < 0.05 was considered statistically significant. Results: All scores improved after CST at both the base and remote centers. The following significant increases were observed: for remote observers: "field" (2.67→4.92; p < .01), "anatomy" (3.58→5.75; p < .01), "dissection" (3.08→4.33; p = .01), and "planning" (3.08→4.33; p < .01); for live observers: "design" (3.75→6.17; p < .01), "field" (2.83→5.17; p < .01), "anatomy" (3.67→5.58; p < .01), "dissection" (3.17→4.58; p < .01), "troubleshooting" (2.33→3.67; p < .01), and "planning" (2.92→4.25; p < .01); and for live participants: "design" (3.83→6.33; p = .02), "field" (2.83→6.83; p < .01), "anatomy" (3.67→5.67; p < .01), "dissection" (2.83→6.17; p < .01), "troubleshooting" (2.17→4.17; p < .01), and "planning" (2.83→4.67; p < .01). Understanding of "design" improved significantly after CST in live observers compared with remote observers (p < .01). Understanding of "field and "dissection" improved significantly after CST in live participants compared with live observers (p = .01, p = .03, respectively). Out of the 12 remote observers, 10 participants (83.3%) reported that interacting with surgical teams was easy because they were not on-site. Conclusions: Although all the responses were subjective and the respondents were aware that observation was inferior to hands-on experience, the results from both centers were equivalent, suggesting that remote learning could potentially be viable when resources are limited.

The Association Between Eating Quickly and Excessive Gestational Weight Gain.

Objectives: Maintaining an appropriate gestational weight gain (GWG) is essential for a safe pregnancy and delivery. This study aimed to determine the association between the habit of eating quickly and the risk of excessive GWG. Methods: We administered a questionnaire on eating habits to 1246 pregnant Japanese women in their second to third trimesters. We categorized the participants into three groups according to their answers to the question "Do you eat quickly?" Group 1, "always" or "usually"; Group 2, "sometimes"; and Group 3, "rarely" or "never." We assessed GWG according to the "The Optimal Weight Gain Chart" (Ministry of Health, Labor and Welfare, Japan), and those who exceeded the criteria were considered "excessive." Logistic regression analysis was performed with the risk of excess GWG as the dependent variable and quick food intake as the independent variable, to obtain relevant odds ratios (ORs) and 95% confidence intervals (CIs). Model 1 was unadjusted, and Model 2 was adjusted for age, prepregnancy body mass index, energy intake, mother's educational attainment, household income, exercise habits, and childbearing experience. Results: The OR (95% CI) for Groups 2 and 3 in Model 1, compared with Group 1, was 0.80 (0.62-1.05) and 0.61 (0.43-0.88), respectively (p for trend = 0.047). In Model 2, the OR (95% CI) for Groups 2 and 3 were 0.73 (0.55-0.96) and 0.59 (0.40-0.86), respectively (p for trend = 0.003). Conclusion: These results suggest that quick food ingestion increases the risk of excessive GWG.

Robot-Assisted Retroperitoneoscopic Diamond Bypass Pyeloplasty.

AIM: Robot (da Vinci Si; Intuitive Surgical, Sunnyvale, CA) assisted retroperitoneoscopic diamond bypass pyeloplasty (R-RDBP) performed for ureteropelvic junction (UPJ) obstruction (n = 5) is presented. METHODS: Patients were placed affected side up and the retroperitoneal space accessed conventionally using 3-4 trocars. The diamond-shaped anastomosis involved incising the lowest part of the renal pelvis 12-15 mm transversely and the ureter distal to the obstruction 10-12 mm longitudinally. The first two sutures were placed retroperitoneoscopically; one from the mid-caudal line of the renal pelvis to the apex of the ureteric incision (the apex of the diamond) and the other from the corner of the incision in the renal pelvis to halfway along the ureteric incision. Trocars were replaced and the robot system docked. The first robot suture was placed between these two sutures, and the anastomosis completed by suturing from posterior to ventral applying minimal tension to keep the anastomosis close to the renal pelvis. All sutures were interrupted absorbable 5-0 monofilament. RESULTS: Mean age at R-RDBP was 4.3 (range: 1-14) years old. Height/weight were average. Preoperative Society for Fetal Urology (SFU) grading was 4.0 in all cases. All repairs were primary and progressed smoothly without perioperative complications; 3/5 had improved appetite postoperatively. Mean SFU grades 1-3 months postoperatively were 2.8, 2.2, and 1.6, respectively. Diuretic renography that was obstructive in all cases preoperatively was normal in four and delayed in one case, postoperatively. CONCLUSION: R-RDBP prevented rotation/kinking of the ureter, enhanced precision of suturing, and maximized the diameter at the anastomosis, facilitating smooth urine flow. LEVEL OF EVIDENCE: LEVEL IV.

Native liver survivors of portoenterostomy for biliary atresia with excellent outcome: redefining "successful" portoenterostomy.

PURPOSE: Native liver survivors (NLS) after portoenterostomy (PE) for biliary atresia (BA) with normal biomarkers defined as total bilirubin (T-Bil), aspartate aminotransferase (AST)/alanine aminotransferase (ALT) for liver function (LF), cholinesterase (ChE), platelet count (PC), and absence of portal hypertension (PHT) were reviewed to redefine "successful" PE. METHODS: 92 post-PE BA patients were classified as NLS-1: normal biomarkers, PHT (-); NLS-2: at least one abnormal biomarker, PHT (-); NLS-3: normal biomarkers, PHT ( +); NLS-4: abnormal biomarkers, PHT ( +) and reviewed for a maximum 32 years. RESULTS: As of June 2022, 55/92 (59.8%) had received liver transplants and 37/92 (40.2%) were NLS. NLS patients were classified as excellent outcome (EO): NLS-1 (n = 10; 27.0%) or non-EO: NLS-2: (n = 8; 21.6%), NLS-3: (n = 6; 16.2%), and NLS-4: (n = 13; 35.1%). Compared with non-EO, EO had PE earlier (50.5 versus 65 days; not significant; p = 0.08), significantly earlier onset of symptoms (13 days versus 32 days; p = 0.01) and significantly shorter jaundice-clearance (JC; 34.5 days versus 56.0 days; p < 0.001). Durations of follow-up were similar: 13 years in EO, 18.5 years in NLS-2, 20 years in NLS-3, and 15 years in NLS-4. CONCLUSION: Incidence of "successful" PE or EO is low and correlated with early onset of symptoms and quicker JC.

Mid-term outcome of postoperative biliary atresia patients according to level of transection of the biliary remnant and depth of suturing.

PURPOSE: Open portoenterostomy (PE) for biliary atresia (BA) is currently more extended (EP) than the original (OP). Typical OP techniques, shallow transection of the biliary remnant and shallow suturing, both lost in EP, were revived as a modified procedure (MP). Postoperative outcomes of EP and MP were compared. METHODS: Subjects were 55 consecutive BA patients treated by EP (n = 18) or MP (n = 37) at a single center between 2004 and 2021. RESULTS: Mean follow-up duration was: MP: 15.5 years (range 0.1-12.3 years) and EP: 15.5 years (range 0.38-17.1 years). The ratio of jaundice free (JF; total bilirubin ≤ 1.2 mg/dL) subjects was significantly higher in MP (78.4%) versus EP (50%); p > 0.05, the incidence of bile lakes at the porta hepatis was significantly higher in MP (7/37: 18.9%) versus EP (0/18: 0%); p > 0.05, and Kaplan-Meier analysis showed JF survival with the native liver (JF + SNL) was significantly better in MP (26/37: 70.2%) versus EP (4/18: 22.2%); p > 0.05. All other criteria were similar. Of note, time taken to become JF and the incidence of cholangitis were not significantly different. CONCLUSIONS: Shallow transection and shallow suturing would appear to influence postoperative outcome. The etiology of bile lake formation in MP requires urgent confirmation.

Decreased incidence of intussusception during the COVID-19 pandemic. Trends in pediatric surgical emergencies.

PURPOSE: Recent reports suggest that the COVID-19 pandemic may be influencing disease morbidity. The purpose of this study was to investigate pandemic-related changes in the incidence of pediatric surgical emergencies. METHODS: Data from patients with one of 8 typical conditions considered to be pediatric emergencies who presented at 3 hospitals close to central Tokyo were collated retrospectively from accident and emergency (AE) department records for 2020 and compared with data for 3 years prior to 2020. RESULTS: All subjects had similar demographic profiles. The total number of pediatric AE attendances from 2017 to 2020 was 2880 (2017: n = 600, 2018: n = 736, 2019: n = 817, and 2020: n = 727). Annual attendances were similar. Of the 8 conditions, there were significantly less cases of intussusception in 2020 than previously (23/727; 3.1% versus 132/2153; 6.1%) p < 0.01 and the number of emergency surgical interventions for intussusception was also significantly less in 2020 (0/23; 0% versus 13/132; 9.8%) p < 0.01. CONCLUSION: The implementation of preventative measures to combat the COVID-19 pandemic in 2020 would appear to have influenced the etiopathogenesis of intussusception enough to significantly decrease its overall incidence and the requirement for emergency surgical intervention.

High-sensitivity CRP reflects insulin resistance in smokers.

AIM: The elevation of high-sensitivity C-reactive protein (hs-CRP) is a strong risk factor for cardio-vascular disease (CVD) and is associated with insulin resistance. The hs-CRP concentration also increases in smokers known to be at a high risk for CVD. We examined whether hs-CRP concentra-tion reflects insulin resistance in smokers. METHODS: The hs-CRP levels were measured in 121 male subjects (54 nonsmokers and 67 smokers) with a normal glucose tolerance. The hs-CRP concentration was compared to the homeostasis model assessment of insulin resistance (HOMA-IR) and other clinical variables related to insulin resistance. RESULTS: Smokers had a 64.5% higher hs-CRP concentration than nonsmokers (p<0.0001). In both nonsmokers and smokers, hs-CRP positively correlated with HOMA-IR (r=0.301, p<0.05 and r=0.312, p<0.01) and fasting insulin (r=0.281, p<0.05 and r=0.356, p<0.01). The correlation between hs-CRP and HOMA-IR or fasting insulin was stronger in smokers than in nonsmokers. In smokers, hs-CRP significantly correlated with BMI and HDL-cholesterol (r=0.386, p<0.01 and r=-0.307, p<0.05). Stepwise regression analysis revealed that BMI and HOMA-IR were significant predictors of hs-CRP in smokers (r=0.423, p<0.01). CONCLUSIONS: The hs-CRP concentration reflects insulin resistance in smokers. It would be preferable to consider insulin resistance in evaluating hs-CRP concentrations, even in smokers.

Risk factors for severe coronary artery disease - a case-control study of patients who have undergone coronary artery bypass grafting.

To investigate risk factors for coronary artery disease (CAD), we analyzed the clinical parameters of patients with a coronary artery bypass graft (CABG) in a case-control study. Eighty-eight patients (75 males and 13 females) who underwent CABG surgery between 2001 and 2002 were compared with age- and sex-matched healthy controls randomly chosen from the registry of Kobari Health Care Center. Wilcoxon's signed rank test and McNemar's test were used for pairwise comparisons. Multivariate logistic regression analysis was used to identify significant risk factors for CABG. Significant differences between the patients and controls were observed in HDL-C (p < 0.001), HbA(1c) (p < 0.001), Brinkman Index (BI; p < 0.001), body mass index (BMI; p = 0.002), and systolic blood pressure (SBP; p = 0.013). Subjects with an abnormal BMI, HbA(1c), or HDL-C or high BI value made up a significantly higher proportion of the patients who underwent CABG, compared to their age- and sex-matched controls. Multivariate logistic regression analysis identified high levels of HbA(1c), low levels of HDL-C, and high scores on the BI as significant risk factors for needing a CABG. These results demonstrate that, despite the modification of laboratory determinations by antecedent treatment, HDL-C, HbA(1c), BI, BMI, and SBP are significant indicators of risk for CAD.

Severe starvation hypoglycemia and congestive heart failure induced by thyroid crisis, with accidentally induced severe liver dysfunction and disseminated intravascular coagulation.

A 69-year-old woman caught a cold resulting in nausea, vomiting, diarrhea and severe anorexia. Then she suffered progressively from dyspnea and leg edema, and finally became delirious. On admission severe hypoglycemia, hypothermia, marked tachycardia, generalized edema, mild jaundice and cachexy were noted. EKG showed atrial fibrillation. A chest X-ray, chest CT and echocardiography showed congestive heart failure. Therapeutic use of diuretics induced shock leading to serious liver dysfunction and disseminated intravascular coagulation. However, combined therapy by intravenous glucose, digitalis, diuretics, anti-fibrinolytic drug and hydrocortisone were effective. Addition of antithyroid therapy brought a further favorable outcome.

Genotype Gly/Gly of the Arg16Gly polymorphism of the beta2-adrenergic receptor is associated with elevated fasting serum insulin concentrations, but not with acute insulin response to glucose, in type 2 diabetic patients.

The beta(2)-adrenergic receptor (B2AR) is expressed in pancreatic beta-cells and modulates insulin secretion. The purpose of the present study was to evaluate the influence of the Arg16Gly variant allele of B2AR on insulin secretion in patients with type 2 diabetes. We used minimal model analysis of the frequently sampled insulin-modified intravenous glucose tolerance test (FSIGT) and polymerase chain reaction (PCR)-restriction fragment length polymorphism to examine differences of insulin secretion and insulin resistance among three genotypes. There were no significant differences in baseline clinical characteristics, HbA1c, uric acid, CRP or lipid profiles among the three groups. The Gly/Gly group had significantly higher levels of fasting insulin (38.2+/-4.7 pmol/l versus 23.6+/-3.5 pmol/l) and homeostasis model assessment of insulin resistance (HOMA-R) (1.90+/-0.19 versus 1.32+/-0.24), compared with the Arg/Arg group, but there were no significant differences in acute insulin response to glucose (AIRg) bolus, insulin sensitivity (Si), or glucose effectiveness (Sg) among the three genotypes. Several reports have speculated that the Gly16 allele of B2AR exhibits agonist-promoted downregulation, but our findings, elevated fasting insulin concentrations, and previous clinical studies of blood pressure and lypolysis are controversial. The direct mechanism by which the Gly16 allele of B2AR may influence insulin secretion of pancreatic beta-cells is unknown. Further studies of the expression of the allelic receptor in islet cells may help to resolve the role of B2AR in insulin secretion. However, increased sensitivity to catecholamine-induced lipolysis of the Gly allele promotes higher free fatty acids concentrations in the portal system, which could enhance the higher levels of fasting insulin.