The Nonhematopoietic Effects of Erythropoietin in Skin Regeneration and Repair: From Basic Research to Clinical Use

Erythropoietin (EPO) is the main regulator of red blood cell production but there exists also a variety of nonhematopoietic properties. More recent data show that EPO is also associated with the protection of tissues suffering from ischemia and reperfusion injury as well as with improved regeneration in various organ systems, in particular the skin. This review highlights the mechanisms of EPO in the different stages of wound healing and the reparative processes in the skin emphasizing pathophysiological mechanisms and potential clinical applications. There is clear evidence that EPO effectively influences all wound‐healing phases in a dose‐dependent manner. This includes inflammation, tissue, and blood vessel formation as well as the remodeling of the wound. The molecular mechanism is predominantly based on an increased expression of the endothelial and inducible nitric oxide (NO) synthase with a consecutive rapid supply of NO as well as an increased content of vascular endothelial growth factor (VEGF) in the wound. The improved understanding of the functions and regulatory mechanisms of EPO in the context of wound‐healing problems and ischemia/reperfusion injury, especially during flap surgery, may lead to new considerations of this growth hormone for its regular clinical application in patients.     

Nonfractionated Heparin Fails to Inhibit Arterial Thrombosis in a Human Ex Vivo Thrombosis Model

−1 for 1 to 4 min. Platelet deposition was determined using immunoenzymatic techniques to quantify P-selectine, a platelet membrane receptor, in thrombi. Fibrin deposition was determined by quantifying fibrin degradation products released after application of plasmin (D-dimers). Heparin was injected into the blood flow through a blender port system located between the venous puncture site and perfusion chamber. The results of the study showed that in a human ex vivo model, formation of arterial thrombus on two thrombogenic surfaces (tissue factor and collagen) is not inhibited by nonfractionated heparin.     

Outpatient Laparoscopic Gastric Banding: Initial Experience

Background: Laparoscopic adjustable gastric banding (LAGB) has usually been performed as an inpatient procedure with an average hospital stay of 2-4 days. The aim of this study was to assess the feasibility of LAGB as an ambulatory procedure in selected patients. Methods: Potential candidates for ambulatory LAGB were recruited from patients consulting for obesity surgery. The main inclusion criteria were BMI >35 kg/m² with co-morbid conditions, living within a reasonable distance from the hospital, and adult company at home. The patients were admitted at 0700 hours on the day of surgery, underwent laparoscopic placement of a Lap-Band^? system and were discharged home that evening. Results: 9 women and 1 man underwent outpatient LAGB. Mean age was 36 (range 18-52) years and mean BMI was 38.4 kg/m² (range 35.1-43.3). Co-morbidities included functional dyspnea (6), osteoarthritis (4), arterial hypertension (4), type 2 diabetes (2) and dyslipidemia (1). 7 patients had undergone previous abdominal surgery: cesarian section (4), appendectomy (3), cholecystectomy (1) and hysterectomy (1). All patients had an American Society of Anesthesiologists (ASA) classification of II. The average operating time was 87 minutes (range 65-115). The mean time lapse between the end of the operation and discharge from hospital was 9.6 hours. There were no readmissions, and no complications were noticed at 1 month postoperatively. The patients' satisfaction with the ambulatory LAGB procedure was high. Conclusion: The present study demonstrates that LAGB for obesity may be performed on an ambulatory basis without complications.     

Natural history of parathyroid function and calcium metabolism after kidney transplantation: a single-centre study.

BACKGROUND: The natural history of parathyroid function after successful renal transplantation (RT) and the factors predisposing to persistent hyperparathyroidism (HPT) are not well established. A better knowledge of these data may be helpful in the development of algorithms for optimal surveillance and treatment of HPT after successful RT. Our aim was to evaluate the post-transplant natural history of parathyroid function and calcium metabolism in patients with a functional renal graft and to identify risk factors for persistent HPT. METHODS: Charts of 1165 allograft kidney recipients transplanted between 1989 and 2000 were reviewed. Patients with an intact parathyroid hormone (iPTH) level available at the time of transplantation were identified. The charts of the latter patients were checked for a variety of demographic and clinical data, and all determinations of the iPTH concentration available since transplantation were recorded. Serum levels of calcium, phosphorus, alkaline phosphatases and creatinine, concurrently determined, were also registered. RESULTS: After an initial fall, iPTH levels showed a slow but steady decline towards the upper normal limit. The prevalence of persistent HPT, defined as an iPTH level > or =2.5 times the upper normal limit or the need for parathyroidectomy following transplantation, remained stable at approximately 17% up to 4 years after transplantation. Patients with persistent HPT had significantly elevated serum levels of iPTH, calcium and phosphorus at the time of RT, and had spent a longer time on dialysis. Post-transplant iPTH levels correlated significantly with transplant kidney function. CONCLUSION: Kidney transplant recipients with a high iPTH and calcium x phosphate product at the time of transplantation are at risk for persistent HPT especially when renal function is suboptimal. Therapy for persistent HPT, if considered, should be initiated 3 months post-transplantation since further spontaneous improvement of parathyroid function thereafter is limited.     

Perioperative cardiorespiratory complications in adults with mediastinal mass: incidence and risk factors

BACKGROUND: Patients with a mediastinal mass are at risk for cardiorespiratory complications in the perioperative period. The authors' objectives were to evaluate the incidence of life-threatening intraoperative cardiorespiratory and postoperative respiratory complications in adult patients and to study the usefulness of clinical signs and symptoms, radiologic evaluation, and pulmonary function tests in the determination of the perioperative risk. METHODS: The authors reviewed the investigation and treatment of adult patients presenting with anterior or middle mediastinal masses for surgery under anesthesia between January 1994 and July 2000. RESULTS: Ninety-eight patients underwent 105 anesthetic cases. The incidences of intraoperative cardiorespiratory and postoperative respiratory complications were 4 in 105 and 11 in 105, respectively. No collapse of the airways occurred during anesthesia. However, a high incidence of early postoperative life-threatening respiratory complications was observed (7 in 105). In a multivariate logistic regression analysis model, perioperative complications were predicted by the occurrence of cardiorespiratory signs and symptoms at the initial presentation (odds ratio [OR], 6.2) and the presence of combined obstructive and restrictive patterns (mixed pulmonary syndrome) on pulmonary function tests (OR, 3.9). Intraoperative complications were associated with pericardial effusion on computed tomography scan (OR, 19.8). Postoperative respiratory complications were related to tracheal compression of more than 50% on preoperative computed tomography scan evaluation (OR, 7.4) and mixed pulmonary syndrome on pulmonary function tests (OR, 15.1). CONCLUSION: Obstruction of the airway in an adult with a mediastinal mass is a rare event in the intraoperative period. Nevertheless, caution should be observed for the occurrence of early postoperative life-threatening respiratory complications. Patient at high risk of perioperative complications can be identified by the occurrence of cardiopulmonary signs and symptoms at presentation, combined obstructive and restrictive pattern on pulmonary function tests, and computed tomography scan findings (tracheal compression > 50%, pericardial effusion, or both).     

Brain‐derived neurotrophic factor prevents dendritic retraction of adult mouse retinal ganglion cells

We used cultured adult mouse retinae as a model system to follow and quantify the retraction of dendrites using diolistic labelling of retinal ganglion cells (RGCs) following explantation. Cell death was monitored in parallel by nuclear staining as ‘labelling’ with RGC and apoptotic markers was inconsistent and exceedingly difficult to quantify reliably. Nuclear staining allowed us to delineate a lengthy time window during which dendrite retraction can be monitored in the absence of RGC death. The addition of brain‐derived neurotrophic factor (BDNF) produced a marked reduction in dendritic degeneration, even when application was delayed for 3 days after retinal explantation. These results suggest that the delayed addition of trophic factors may be functionally beneficial before the loss of cell bodies in the course of conditions such as glaucoma.     

Prospective, Multicenter, 3-Year Trial of Laparoscopic Adjustable Gastric Banding with the MIDBAND?

Background

Although laparoscopic adjustable gastric banding (LAGB) is a popular metabolic/bariatric procedure, few prospective studies have assessed its outcomes. This study aimed to prospectively assess LAGB safety and effectiveness outcomes using the MIDBAND? (MID, Dardilly, France).

Methods

Between May 2005 and September 2006, 262 morbidly obese patients underwent primary gastric banding with pars flaccida technique in 13 French medical centers. Excess weight loss and change in body mass index (BMI, kilogram per square meter), percentage of patients with comorbidities, and obesity-related complications were recorded. Patients were followed at 6-month intervals for 3?years. A multivariable individual growth model was used to analyze weight change over time and determine potential predictors of weight loss.

Results

The majority of patients were female (n?=?233, 89%), with mean age of 36.4?±?9.7?years. At 3?years, LAGB with MIDBAND resulted in significant decrease in mean BMI from 41.8?±?4.2 to 30.7?±?5.8 (p?p?Conclusion Prospective outcomes demonstrate the safety and efficacy of gastric banding over time using the MIDBAND. Individual growth modeling demonstrated that postoperative weight loss is strongly related to the frequency and consistency of follow-up visits.