Induced adiposity and adipocyte hypertrophy in mice lacking the AMP-activated protein kinase-alpha2 subunit

AMP-activated protein kinase (AMPK) is considered as a cellular energy sensor that regulates glucose and lipid metabolism by phosphorylating key regulatory enzymes. Despite the major role of adipose tissue in regulating energy partitioning in the organism, the role of AMPK in this tissue has not been addressed. In the present study, we subjected AMPKalpha2 knockout (KO) mice to a high-fat diet to examine the effect of AMPK on adipose tissue formation. Compared with the wild type, AMPKalpha2 KO mice exhibited increased body weight and fat mass. The increase in adipose tissue mass was due to the enlargement of the preexisting adipocytes with increased lipid accumulation. However, we did not observe any changes in adipocyte marker expression, such as peroxisome proliferator-activated receptor-gamma, CCAAT/enhancer-binding protein alpha (C/EBPalpha) and adipocyte fatty acid-binding protein (aFABP/aP2), or total cell number. Unlike impaired glucose homeostasis observed on normal diet feeding, when fed a high-fat diet AMPKalpha2 KO mice did not show differences in glucose tolerance and insulin sensitivity compared with wild-type mice. Our results suggest that the increase in lipid storage in adipose tissue in AMPKalpha2 KO mice may have protected these mice from further impairment of glucose homeostasis that normally accompanies high-fat feeding. Our study also demonstrates that lack of AMPKalpha2 subunit may be a factor contributing to the development of obesity.     

Functional quality of life following open valve surgery in high-risk octogenarians

Abstract Aim: The aim of this study was to determine the midterm functional quality of life in octogenarians after open valvular surgery. Methods: One hundred and eighty‐five consecutive patients above age 80 had valvular surgery with or without coronary artery bypass grafting (CABG). Using the Karnofsky Performance score and Barthel Index, patients were evaluated for functional autonomy, living disposition, and leisure activity by a single telephone interview. Subgroup analysis was performed on the 49 cases of isolated aortic valve replacement (AVR). Results: Mean age of octogenarians undergoing valvular surgery was 82.7 years (range 80 to 92 years). Actuarial survival at one and three years was 71% and 59%, respectively, for the entire group, compared to 84% and 71%, respectively, for isolated AVRs. After a mean follow‐up of 38 months there were 110 survivors (59.5%). Among survivors, 66% were autonomous, 26% semiautonomous, and 8% deemed dependent. Seventy‐two percent were living at home, 19% in a residence, and 9% in a supervised nursing facility. Over 90% of patients pursued leisure activities in the social, cognitive, and physical domains. Conclusions: Valvular surgery in high‐risk octogenarians, can be performed with acceptable mortality rates, and provide patients with functional autonomy and an excellent quality of life. (J Card Surg 2012;27:408‐414)     

Evidence of trochlear dysplasia in patellofemoral arthroplasty designs

Purpose

The design of the trochlear compartment is crucial in patellofemoral arthroplasty (PFA), because 78 % of patients with isolated patellofemoral arthritis present concomitant trochlear dysplasia with patellar maltracking and therefore remain predisposed to post-operative patellar subluxation and dislocation. The study investigated whether current PFA implants are designed with anatomic trochlear parameters such as the sulcus angle, lateral facet height and groove orientation.

Methods

Five trochlear components of commercially available PFA implants were scanned, and the generated three-dimensional surfaces were measured using engineering design software. The mediolateral trochlear profiles were plotted at various flexion angles (0°, 15°, 30° and 45°) to deduce the following variables: sulcus angle, height of lateral facet and trochlear groove orientation.

Results

Four specimens had sulcus angle >144° in the 45° of flexion, and all five specimens had sulcus angle >143° in 30° of flexion. Three specimens had a facet <5 mm high through the entire range of early flexion (0°–30°), and two specimens had a facet <5 mm high beyond early flexion (30°–45°). The trochlear groove was oriented laterally in all specimens (range 1.6°–13.5°).

Conclusion

Current PFA trochlear components are not always designed with anatomic parameters, and some models exhibit characteristics of trochlear dysplasia. Surgeons are therefore advised to implant components with a deep sulcus, particularly in patients with history of patellofemoral disorders, and to adapt the surgical technique and extensor mechanism if the component implanted has a shallow sulcus, to ensure normal patellar tracking.

Level of evidence

III.     

Liver Recurrence of a Subcutaneous Temporal Hemangiopericytoma: The Index Case

Introduction  Hemangiopericytoma is an uncommon soft tissue vascular neoplasm. Intraperitoneal hemangiopericytomas such as primary or secondary liver location have been exceptionally described. Its natural history is mostly benign, but recurrences may occur and determining if these late-discovered tumors are distant metastases or synchronous slow and silent-growing locations is sometimes challenging. The histopathological diagnosis and definition of hemangiopericytoma is based on its distinction with solitary fibrous tumors. Liver resection to treat liver hemangiopericytoma seems to be supported by various published experiences. Case presentation  We herein report the first case of liver metastases from a subcutaneous temporal hemangiopericytoma. The patient was treated by a liver resection. CD34 Immunostaining was negative, but strong expression of Bcl2 and CD99 was found in the neoplastic cells. After 1 year of follow-up, the patient is alive without recurrence. Conclusion  To date, published data, including the case herein reported, support the need for a prolonged follow-up and the role of liver resection to treat liver metastases of hemangiopericytomas. Complete resection of all gross disease appears to be the most significant prognostic factor.     

Quantitative in vivo islet potency assay in normoglycemic nude mice correlates with primary graft function after clinical transplantation

Reliable assays are critically needed to monitor graft potency in islet transplantation (IT). We tested a quantitative in vivo islet potency assay (QIVIPA) based on human C-peptide (hCP) measurements in normoglycemic nude mice after IT under the kidney capsule. QIVIPA was initially tested by transplanting incremental doses of human islets. hCP levels in mice were correlated with the number of transplanted islet equivalents (r(2) = 0.6, P<0.01). We subsequently evaluated QIVIPA in eight islet preparations transplanted in type 1 diabetic patients. Conversely to standard criteria including islet mass, viability, purity, adenosine triphosphate content, or glucose stimulated insulin secretion, hCP in mice receiving 1% of the final islet product was correlated to primary graft function (hCP increase) after IT (r(2)=0.85, P<0.01). QIVIPA appears as a reliable test to monitor islet graft potency, applicable to validate new methods to produce primary islets or other human insulin secreting cells.     

Liver resection for breast cancer metastasis: Does it improve survival?

Purpose To assess the outcome and prognostic factors of liver surgery for breast cancer metastasis. Methods We retrospectively examined 16 patients who underwent partial liver resection for breast cancer liver metastasis (BCLM). All patients had been treated with chemotherapy or hormonotherapy, or both, before referral for surgery. We confirmed by preoperative radiological examinations that metastasis was confined to the liver. The survival curve was estimated using the Kaplan-Meier method. Univariate and multivariate analysis were conducted to evaluate the role of the known factors of breast cancer survival. Results The median age of the patients was 54 years (range 38–68) and the median disease-free interval between the diagnoses of breast cancer and liver metastasis was 54 months (range 7–120). Nine major and 7 minor hepatectomies were performed. There was no postoperative death. The overall 1-, 3-, and 5-year survival rates were 94%, 61%, and 33%, respectively. The median survival rate was 42 months. Univariate analysis revealed that hormone receptor status, number of metastases, a major hepatectomy, and a younger age were associated with a poorer prognosis. The survival rate was not influenced by the disease-free interval, grade or stage of breast cancer, or intraoperative blood transfusions. The number of liver metastases was identified as a significant independent factor of survival according to the Cox proportional hazard model (P = 0.04). Conclusions Liver resection, when done in combination with adjuvant therapy, can improve the prognosis of selected patients with BCLM.     

Vascular renal anatomy and the ureteropelvic junction: preoperative multidetector CT scanning with split-bolus injection as a predictor of laparoscopic findings

PURPOSE: To compare multidetector CT scan (MDCT) results with intraoperative findings in the detection of an inferior-pole pedicle crossing the ureteropelvic junction. PATIENTS AND METHODS: Over the 2-year study period, 35 patients receiving laparoscopic pyeloplasty underwent preoperative investigation with a novel MDCT protocol in order to detect crossing vessels. Postprocessing, including maximum intensity projection, volume-rendering technique, and multiplanar reconstruction, was used in addition to standard axial views. RESULTS: All the arteries found during laparoscopic surgery were detected by MDCT, but one radiologic false-positive was noted at the beginning of the series. Seven veins were not detected with MDCT. In the only case featuring an isolated inferior-pole vein, the aberrant vessel was identified by MDCT. CONCLUSION: Multidetector CT scanning is a highly accurate way of providing all the information necessary preoperatively concerning renal parenchymal anomalies, urinary stones, and collecting system and vessel anatomy. It helps physicians make appropriate therapeutic decisions and gives surgeons information about what they can expect during laparoscopic procedures.     

Scrotal ulcer after intraperitoneal hyperthermic chemotherapy

Tumor cytoreduction combined with intraperitoneal hyperthermic chemotherapy has been shown to be an effective method to delay the progression of peritoneal carcinomatosis. We describe 2 cases of painful scrotal ulcer after tumor debulking and intraperitoneal infusion of mitomycin-C for treatment of metastatic abdominal malignancies. Although the pathogenesis is unknown, the awareness of its presence and early signs of clinical presentations by clinicians is very important.     

Optimal donation of kidney transplants after controlled circulatory death

Controlled donation after circulatory death (cDCD) is used for “extended criteria” donors with poorer kidney transplant outcomes. The French cDCD program started in 2015 and is characterized by normothermic regional perfusion, hypothermic machine perfusion, and short cold ischemia time. We compared the outcomes of kidney transplantation from cDCD and brain-dead (DBD) donors, matching cDCD and DBD kidney transplants by propensity scoring for donor and recipient characteristics. The matching process retained 442 of 499 cDCD and 809 of 6185 DBD transplantations. The DGF rate was 20% in cDCD recipients compared with 28% in DBD recipients (adjusted relative risk [aRR], 1.43; 95% confidence interval [CI] 1.12–1.82). When DBD transplants were ranked by cold ischemia time and machine perfusion use and compared with cDCD transplants, the aRR of DGF was higher for DBD transplants without machine perfusion, regardless of the cold ischemia time (aRR with cold ischemia time <18 h, 1.57; 95% CI 1.20–2.03, vs aRR with cold ischemia time ≥18 h, 1.79; 95% CI 1.31–2.44). The 1-year graft survival rate was similar in both groups. Early outcome was better for kidney transplants from cDCD than from matched DBD transplants with this French protocol.