Assessment of self-rated health 5 years after Roux-en-Y gastric bypass for severe obesity.

Background: Patients' perceptions of health change after bariatric surgery are complex. The aim of this study was to explore whether self-rated health (SRH), a widely used tool in public health research, might be relevant as an outcome measure after Roux-en-Y gastric bypass (RYGB) for severe obesity. Methods: This was a single-centre retrospective study of a local quality registry. SRH score was registered at baseline and 5 years after RYGB. SRH, one of the 36 items in the quality-of-life Short Form 36 (SF-36®) questionnaire, is the answer to this single question: 'In general, would you say your health is excellent (1), very good (2), good (3), fair (4) or poor (5)?' Change in SRH was analysed in relation to change in weight, co-morbidities and quality of life after 5 years. Results: Of a total of 359 patients who underwent RYGB between September 2006 and February 2011, 233 (64·9 per cent) reported on SRH before and 5 years after surgery. Of these, 180 (77·3 per cent) were women, and the mean(s.d.) age was 40(9) years. Some 154 patients (66·1 per cent) reported an improvement in SRH, 60 (25·8 per cent) had no change, and SRH decreased in 19 patients (8·2 per cent). SRH in improvers was related to better scores in all SF-36® domains, whereas SRH in non-improvers was related to unchanged or worsened scores in all SF-36® domains except physical function. Conclusion: Two-thirds of patients reported improved SRH 5 years after RYGB for severe obesity. In view of its simplicity, SRH may be an easy-to-use outcome measure in bariatric surgery.

Antecedentes: Las percepciones de los pacientes del cambio de su salud tras la cirugía bariátrica son complejas. El objetivo de este estudio fue examinar si la autovaloración de la salud (self­rated health, SRH), una herramienta ampliamente utilizada en investigación en salud pública, podría ser relevante como medida de resultado después del bypass gástrico en Y de Roux (Roux­en­Y gastric bypass, RYGB) para la obesidad severa. Métodos: Se llevó a cabo un estudio retrospectivo de un registro de calidad local de un único centro. La SRH se recogió en situación basal y a los 5 años tras el RYGB. SRH es una de las 36 preguntas del cuestionado de calidad de vida SF­36 (forma corta) y consiste en la respuesta a esta única pregunta: "En general, diría que su salud es excelente (1), muy buena (2), buena ( 3), razonable (4) o pobre (5)?". Resultados: De un total de 359 pacientes sometidos a un RYGB en el periodo entre septiembre de 2006 y febrero de 2011, 233 (65%) informaron del SRH antes y a los 5 años de la cirugía. De ellos, 180 (77,3%) eran mujeres y la edad media era de 40 (DE 9) años. La SRH mejoró en 154 (66,1%) pacientes, no experimento cambios en 60 (25,8%) y disminuyó en 19 (8,2%). En tanto que la mejoría de la SRH se relacionó con mejores puntuaciones en todos los dominios de cuestionario SF­36, la no mejoría se relacionó con puntuaciones iguales o peores en todos los dominios del SF­36, a excepción de la función física. Conclusión: Dos tercios de los pacientes reportaron mejoría de la SRH a los 5 años tras un RYGB por obesidad grave, y debido a su simplicidad, la SRH podría constituir una medida de resultado, de fácil uso, en cirugía bariátrica.

Investigation of the long-term sustainability of changes in appetite after weight loss.

BACKGROUND/OBJECTIVE: Diet-induced weight loss (WL) leads to a compensatory increase in appetite and changes in the plasma concentration of appetite-regulating hormones are likely to play a role. Whether these changes are transient or sustained remains unclear. This study aimed to assess if changes in subjective and objective appetite markers observed with WL are sustained after 1 year (1Y). SUBJECTS/METHODS: In total 100 (45 males) individuals with obesity (BMI: 37 ± 4 kg/m2, age: 43 ± 10 years) underwent 8 weeks (wks) of a very-low energy diet (VLED), followed by 4 wks refeeding, and a 1Y maintenance program. Fasting/postprandial subjective ratings of hunger, fullness, desire to eat, and prospective food consumption (PFC) were assessed, and plasma concentration of active ghrelin (AG), total peptide YY (PYY), active glucagon-like peptide 1, cholecystokinin (CCK), and insulin measured, at baseline, week 13 (Wk13) and 1Y. RESULTS: At Wk13, 16% WL (-18 ± 1 kg, P < 0.001) was associated with a significant increase in fasting and postprandial hunger ratings (P < 0.01 and P < 0.05, respectively), and postprandial fullness (P < 0.01) combined with a reduction in PFC (P < 0.001). These were accompanied by a significant rise in basal and postprandial AG concentrations (P < 0.001, for both), a reduction in postprandial CCK (P < 0.01) and in basal and postprandial insulin (P < 0.001). At 1Y follow-up, with sustained WL (15%; -16 ± 1 kg, P < 0.001), fasting hunger and postprandial fullness ratings remained increased (P < 0.05 for both), and postprandial PFC reduced (P < 0.001). Basal and postprandial AG remained elevated and insulin reduced (P < 0.001, for all), while postprandial CCK was increased (P < 0.01) and PYY decreased (P < 0.001). CONCLUSION: With a 15% sustained WL at 1Y, the drive to eat in the fasting state is increased, but this may be balanced out by raised postprandial feelings of fullness. To assist with WL maintenance, new strategies are required to manage increased hunger and drive to eat.

Impact of weight loss achieved through a multidisciplinary intervention on appetite in patients with severe obesity.

The impact of lifestyle-induced weight loss (WL) on appetite in patients with obesity remains controversial. This study aimed to assess the short- and long-term impact of WL achieved by diet and exercise on appetite in patients with obesity. Thirty-five (22 females) adults with severe obesity (body mass index: 42.5 ± 5.0 kg/m2) underwent a 2-yr WL program focusing on diet and exercise. Body weight (BW), cardiovascular fitness (V̇o2max), appetite feelings, and plasma concentrations of insulin, active ghrelin (AG), glucagon-like peptide 1 (GLP-1), peptide YY (PYY), and cholecystokinin (CCK), in the fasting and postprandial states, were measured at baseline (B), week 4 (W4), and 1 and 2 yr (and average values for all fasting and postprandial time points computed). BW was significantly reduced and V̇o2max (ml·kg-1·min-1) increased at all time points compared with B (3.5, 8.1, and 8.4% WL and 7, 11, and 8% increase at W4 and 1 and 2 yr, respectively). Basal hunger and average hunger and desire to eat were significantly increased at 1 and 2 yr. Basal fullness was significantly increased at W4, and average ratings were reduced at 1 yr. Average AG and PYY were significantly increased, and insulin was reduced, at all time points compared with B. Average GLP-1 was reduced at W4, and CCK was increased at 2 yr. After lifestyle-induced WL, patients with severe obesity will, therefore, have to deal with increased hunger in the long term. In conclusion, sustained WL at 2 yr achieved with diet and exercise is associated with increased hunger feelings and ghrelin concentration but also increased postprandial concentrations of satiety hormones.

The effect of hypergastrinemia following sleeve gastrectomy and pantoprazole on type 2 diabetes mellitus and beta-cell mass in Goto-Kakizaki rats.

PURPOSE: Metabolic surgery alters the secretion of gastrointestinal hormones that influence glycemic control. Elevated gastrin has been suggested to benefit patients with type 2 diabetes and has been reported following sleeve gastrectomy in rats. The present study compares the effect of hypergastrinemia following sleeve gastrectomy with proton-pump inhibitor therapy on glycemic control and beta-cell mass in lean, diabetic animals. METHODS: Thirty-three diabetic Goto-Kakizaki rats were randomized into pantoprazole + sham operation (GK-PPI), sleeve gastrectomy (GK-SG) and vehicle + sham operation (GK-V). Body weight, glucose parameters, HbA1c, glucagon-like peptide 1, gastrin, insulin and lipids were evaluated for eighteen postoperative weeks. Total beta-cell mass was quantified by optical projection tomography. RESULTS: After surgery, body weight development was equal among groups (P g = 0.75). Fasting and stimulated gastrin increased for GK-PPI and GK-SG vs. GK-V (p < 0.05 for all). Fasting blood glucose was decreased for GK-PPI and GK-SG vs. GK-V (p < 0.05 and p = 0.052). HbA1c was lower for GK-SG vs. GK-V at 6 weeks and for GK-PPI vs. GK-V at twelve- and eighteen weeks postoperative (p < 0.05 for all); a borderline difference was observed for GK-SG vs. GK-V at 18 weeks (p = 0.054). Total- and LDL cholesterol was elevated for GK-PPI compared to the other two groups (p < 0.05 for all). Beta-cell mass did not differ among groups (p = 0.35). CONCLUSIONS: Hypergastrinemia following sleeve gastrectomy and pantoprazole has a similar, modest effect on glycemic control in Goto-Kakizaki rats but does not enhance beta-cell mass after 18 weeks. Hypergastrinemia in the setting of T2DM might be of clinical relevance.

Timeline of changes in appetite during weight loss with a ketogenic diet.

BACKGROUND/OBJECTIVE: Diet-induced weight loss (WL) leads to increased hunger and reduced fullness feelings, increased ghrelin and reduced satiety peptides concentration (glucagon-like peptide-1 (GLP-1), cholecystokinin (CCK) and peptide YY (PYY)). Ketogenic diets seem to minimise or supress some of these responses. The aim of this study was to determine the timeline over which changes in appetite occur during progressive WL with a ketogenic very-low-energy diet (VLED). SUBJECTS/METHODS: Thirty-one sedentary adults (18 men), with obesity (body mass index: 37±4.5 kg m-2) underwent 8 weeks (wks) of a VLED followed by 4 wks of weight maintenance. Body weight and composition, subjective feelings of appetite and appetite-related hormones (insulin, active ghrelin (AG), active GLP-1, total PYY and CCK) were measured in fasting and postprandially, at baseline, on day 3 of the diet, 5 and 10% WL, and at wks 9 and 13. Data are shown as mean±s.d. RESULTS: A significant increase in fasting hunger was observed by day 3 (2±1% WL), (P<0.01), 5% WL (12±8 days) (P<0.05) and wk 13 (17±2% WL) (P<0.05). Increased desire to eat was observed by day 3 (P<0.01) and 5% WL (P<0.05). Postprandial prospective food consumption was significantly reduced at wk 9 (16±2% WL) (P<0.01). Basal total PYY was significantly reduced at 10% WL (32±8 days) (P<0.05). Postprandial active GLP-1 was increased at 5% WL (P<0.01) and CCK reduced at 5 and 10% WL (P<0.01, for both) and wk 9 (P<0.001). Basal and postprandial AG were significantly increased at wk 13 (P<0.001, both). CONCLUSIONS: WL with a ketogenic VLED transiently increases the drive to eat up to 3 weeks (5% WL). After that, and while participants are ketotic, a 10-17% WL is not associated with increased appetite. However, hunger feelings and AG concentrations increase significantly from baseline, once refeeding occurs.

Bariatric surgery versus lifestyle interventions for severe obesity: 5-year changes in body weight, risk factors and comorbidities.

Changes in body weight (BW), risk factors and comorbidities 5 years after Roux-en-Y gastric bypass (RYGB) or different lifestyle interventions are compared. A total of 209 (75% women) severe obese adults were non-randomly allocated to: (A) RYGB (n = 58), (B) weight loss (WL) camp (n = 30), (C) residential intermittent programme (n = 64) or (D) hospital outpatient programme (n = 57). Body weight, risk factors and comorbidities were assessed at baseline, 1 and 5 years. A total of 89 and 54% completed the 1- and 5-year follow-up. The RYGB group experienced more WL at 5 years (-23.9%, 95% CI [-27.7, -20.0]) compared with lifestyle groups: (B) (-9.2%, 95% CI [-16.9, -1.5]), (C) (-4.1%, 95% CI [-8.0, -0.1]) and (D) (-4.1 kg, 95% CI [-10.0, 1.8]) (all P < 0.001). No differences were observed between lifestyle groups, although groups B and C had significant WL after 5 years (all P < 0.05). Plasma glucose and high-density lipoprotein cholesterol were improved in the RYGB group at 5 years compared with lifestyle groups (all P < 0.05). More patients in the RYGB group experienced remission of hypertension (P < 0.05). RYGB was associated with a lower BW, improved blood parameters and hypertension remission compared with lifestyle interventions at 5 years. However, significant WL was also achieved with lifestyle interventions.

Baker's yeast (Saccharomyces cerevisiae) antigen in obese and normal weight subjects.

Baker's yeast (Saccharomyces cerevisiae) and its cell wall components have been used as one of the alternatives to antibiotic growth promoters in the feed industry. Antibodies to cell wall mannan of this yeast (ASCA) have been traditionally used in the study of Crohn's disease (CD). We applied ASCA in relation to obesity. This study aims (i) to determine the concentration of ASCA (immunoglobulin A [IgA] and immunoglobulin G [IgG]) in obese compared with normal weight individuals and (ii) to determine if there is a correlation between ASCA concentrations, obesity indices and C-reactive protein. Forty obese individuals (body mass index [BMI] > 35 kg m(-2) ) and 18 healthy (BMI < 25 kg m(-2) ) volunteers participated in this case-control study. Binding activity of serum IgA and IgG to the cell wall mannan of S. cerevisiae was measured by enzyme-linked immunosorbent assay. More than one-third of the obese individual (35%) showed elevated titres of ASCA compared with the control group (5%). This antibody was positively associated with weight (P = 0.01), BMI (P = 0.02) and waist circumference (P = 0.02), but not with C-reactive protein. It seems that ASCA are not only specific for CD but are also associated with obesity. S. cerevisiae or a related antigen may play a role in the matrix of this complex condition.

Effects of duodenal switch alone or in combination with sleeve gastrectomy on body weight and lipid metabolism in rats.

BACKGROUND: A combined procedure of sleeve gastrectomy and duodenal switch (SG+DS) has been applied to the treatment of super obesity. The aim of the present study was to test whether duodenal switch alone (DS) leads to similar weight loss and changes in lipid metabolism as SG+DS. METHODS: Male Sprague-Dawley rats underwent sham surgery (Sham, N=7), duodenal switch alone (DS, N=5) or sleeve gastrectomy followed by duodenal switch (SG+DS, N=5). Body weight, feed and water intakes, and ambulatory activity were recorded 2 months post surgery. Tissue and faecal lipids, faecal bile acids, plasma cytokines and lipid metabolism-related gene expression in adipose tissue and liver were analysed. RESULTS: Daily energy intake, relative feed uptake, ambulatory activity and body weight reduction were similar between DS and SG+DS rats. The hepatic triacylglycerol content was higher and faecal secretion of triacylglycerol was lower after SG+DS compared to DS (P<0.05). Faecal bile acid secretion was higher in SG+DS than in DS rats (P<0.05) despite similar hepatic CYP7A1mRNA level. Plasma levels of proinflammatory cytokines interleukin (IL)-1b, IL-2, IL-4, IL-5, IL-6, IL-12, granulocyte-macrophage colony stimulating factor and tumour necrosis factor alpha were higher in SG+DS than in DS rats (P<0.05). CONCLUSIONS: Although DS and SG+DS had similar efficacy in terms of body weight loss, SG+DS resulted in a poorer regulation of lipid metabolism than DS.

Vagal blocking improves glycemic control and elevated blood pressure in obese subjects with type 2 diabetes mellitus.

BACKGROUND: An active device that downregulates abdominal vagal signalling has resulted in significant weight loss in feasibility studies. OBJECTIVE: To prospectively evaluate the effect of intermittent vagal blocking (VBLOC) on weight loss, glycemic control, and blood pressure (BP) in obese subjects with DM2. METHODS: Twenty-eight subjects were implanted with a VBLOC device (Maestro Rechargeable System) at 5 centers in an open-label study. Effects on weight loss, HbA1c, fasting blood glucose, and BP were evaluated at 1 week to 12 months. RESULTS: 26 subjects (17 females/9 males, 51 ± 2 years, BMI 37 ± 1 kg/m(2), mean ± SEM) completed 12 months followup. One serious adverse event (pain at implant site) was easily resolved. At 1 week and 12 months, mean excess weight loss percentages (% EWL) were 9 ± 1% and 25 ± 4% (P < 0.0001), and HbA1c declined by 0.3 ± 0.1% and 1.0 ± 0.2% (P = 0.02, baseline 7.8 ± 0.2%). In DM2 subjects with elevated BP (n = 15), mean arterial pressure reduced by 7 ± 3 mmHg and 8 ± 3 mmHg (P = 0.04, baseline 100 ± 2 mmHg) at 1 week and 12 months. All subjects MAP decreased by 3 ± 2 mmHg (baseline 95 ± 2 mmHg) at 12 months. CONCLUSIONS: VBLOC was safe in obese DM2 subjects and associated with meaningful weight loss, early and sustained improvements in HbA1c, and reductions in BP in hypertensive DM2 subjects. This trial is registered with ClinicalTrials.gov NCT00555958.

The effects of exercise-induced weight loss on appetite-related peptides and motivation to eat.

CONTEXT: The magnitude of exercise-induced weight loss depends on the extent of compensatory responses. An increase in energy intake is likely to result from changes in the appetite control system toward an orexigenic environment; however, few studies have measured how exercise impacts on both orexigenic and anorexigenic peptides. OBJECTIVE: The aim of the study was to investigate the effects of medium-term exercise on fasting/postprandial levels of appetite-related hormones and subjective appetite sensations in overweight/obese individuals. DESIGN AND SETTING: We conducted a longitudinal study in a university research center. PARTICIPANTS AND INTERVENTION: Twenty-two sedentary overweight/obese individuals (age, 36.9 +/- 8.3 yr; body mass index, 31.3 +/- 3.3 kg/m(2)) took part in a 12-wk supervised exercise programme (five times per week, 75% maximal heart rate) and were requested not to change their food intake during the study. MAIN OUTCOME MEASURES: We measured changes in body weight and fasting/postprandial plasma levels of glucose, insulin, total ghrelin, acylated ghrelin (AG), peptide YY, and glucagon-like peptide-1 and feelings of appetite. RESULTS: Exercise resulted in a significant reduction in body weight and fasting insulin and an increase in AG plasma levels and fasting hunger sensations. A significant reduction in postprandial insulin plasma levels and a tendency toward an increase in the delayed release of glucagon-like peptide-1 (90-180 min) were also observed after exercise, as well as a significant increase (127%) in the suppression of AG postprandially. CONCLUSIONS: Exercise-induced weight loss is associated with physiological and biopsychological changes toward an increased drive to eat in the fasting state. However, this seems to be balanced by an improved satiety response to a meal and improved sensitivity of the appetite control system.

Prevalence of all relevant eating disorders in patients waiting for bariatric surgery: a comparison between patients with and without eating disorders.

OBJECTIVE: To study the prevalence of all relevant eating disorders in 157 obese patients waiting for bariatric surgery. Another aim was to explore for possible differences between gender, and those with and without ED. The dependent variables were: socio-demographic characteristics, BMI, obesity onset, and obesity-related somatic diseases. METHODS: ED was assessed using the self-report questionnaire, "Eating Disorders in Obesity" (EDO). The patients answered a questionnaire that targeted socio-demographic and health information. RESULTS: Subgroups were based on the patients responses to items on the EDO: 1 patient (0.6%) with Bulimia Nervosa (BN), 6 (3.8%) with Eating Disorder Not Otherwise Specified (EDNOS), 21 (13.4%) with Binge Eating Disorder (BED), and 23 (14.6%) with Binge Eating (BE). The patients in the EDNOS group were those who lacked one criterion of the BN diagnosis. The patients in the BE group lacked one criterion of the BED diagnosis. Twenty-eight (17.8%) fulfilled the DSM-IV-TR criteria for ED. When patients with BE were added, 51 patients (32.5%) were identified with ED or sub-threshold ED. In the explorative part of the study, no gender differences in socio-demographic variables, BMI, obesity onset, and obesity-related somatic diseases emerged. With the exception of age, no differences were found in these variables between those with and without ED. CONCLUSION: Employing all relevant eating disorders and binge eating symptoms (BE) for this population identified patients with pathological eating behaviors, which are not detected in previous studies measuring only BED and BE.

Feeding behavior and body weight development: lessons from rats subjected to gastric bypass surgery or high-fat diet.

Weight loss treatments include diets, drugs, physical training, and surgery, namely bariatric or obesity surgery. The current standard for bariatric surgery is gastric bypass. There are common beliefs that gastric bypass induces body weight loss because of a reduced food intake and that high-fat diet induces overweight and obesity because of overnutrition. The principal aim of the studies on rats summarized herein was to better understand the physiological mechanisms by which gastric bypass achieves body weight loss and by which high-fat diet induces obesity. The results indicated that gastric bypass efficiently reduced body weight, particularly the fat compartment, which was unlikely to be caused by early satiety, reduced food intake or malabsorption, and that large meal size, but not overnutrition, was mainly responsible for high-fat diet-induced obesity. It was unclear whether gastric ghrelin, obestatin and/or amine in the A-like cells were involved in this context.

Intra-abdominal vagal blocking (VBLOC therapy): clinical results with a new implantable medical device.

BACKGROUND: A new medical device uses high-frequency electrical algorithms to create intermittent vagal blocking (VBLOC therapy). The aim is to assess the effects of vagal blocking on excess weight loss (EWL), safety, dietary intake, and vagal function. METHODS: An open-label, 3-center study was conducted in obese subjects (body mass index [BMI] 35-50 kg/m(2)). Electrodes were implanted laparoscopically on both vagi near the esophagogastric junction to provide electrical block. Patients were followed for 6 months for body weight, safety, electrocardiogram, dietary intake, satiation, satiety, and plasma pancreatic polypeptide (PP) response to sham feeding. To specifically assess device effects alone, no diet or exercise programs were instituted. RESULTS: Thirty-one patients (mean BMI, 41.2 +/- 1.4 kg/m(2)) received the device. Mean EWL at 4 and 12 weeks and 6 months after implant was 7.5%, 11.6%, and 14.2%, respectively (all P < .001); 25% of patients lost >25% EWL at 6 months (maximum, 36.8%). There were no deaths or device-related serious adverse events (AEs). Calorie intake decreased by >30% at 4 and 12 weeks and 6 months (all P 25 pg/mL (P = .02). Three patients had serious AEs that required brief hospitalization, 1 each for lower respiratory tract, subcutaneous implant site seroma, and Clostridium difficile diarrhea. CONCLUSIONS: Intermittent, intra-abdominal vagal blocking is associated with significant EWL and a desirable safety profile.

Feeding behavior in rats subjected to gastrectomy or gastric bypass surgery.

BACKGROUND/AIM: Gastric bypass (GB) is usually designed to restrict food intake and to induce malabsorption. Gastric hormones have been thought to play a role in the regulation of food intake and body weight. The aim of the present study was to analyze feeding behavior after total gastrectomy (Gx) or GB in rats. METHODS: Animals were subjected to Gx, GB, or sham operations. Eating and drinking behaviors after surgeries were assessed by a comprehensive laboratory animal monitoring system. Gastric hormones were measured by radioimmunoassay and energy density in feces by adiabatic bomb calorimeter. RESULTS: Compared with sham operation, both Gx and GB reduced the body weight as measured during 3-8 weeks postoperatively, which was associated with increased energy expenditure per 100 g body weight. Daily accumulated food intake and meal size (during nighttime) were reduced following Gx, but not GB. The water intake (during daytime) was increased after Gx and GB. The energy density in feces was unchanged. Serum concentrations of ghrelin, obestatin, leptin, gastrin, and pancreastatin were greatly reduced after Gx. CONCLUSIONS: Control of food intake and meal size was independent of the food reservoir function of the stomach. Surgical depletion of gastric hormones is associated with reduced meal size, but increased water intake.

Is insulin growth factor-1 (IGF-1) playing a role for aneurysm formation in patients with pituitary gland tumor?

The combination of pituitary gland tumor and aneurysmal disease has previously been described. Most of these aneurysms have affected intracranial arteries. The purpose is to present 2 patients with thoracoabdominal aortic aneurysm and pituitary gland tumor and further to discuss the mechanism behind this combination of diseases. A 59-year-old male patient was admitted with abdominal pain and a 120 mm thoracoabdominal aortic aneurysm type III. He was operated with resection and graft replacement. During the operation, it was noted that his intra-abdominal arteries were extremely enlarged. The diagnosis acromegaly was confirmed in the late 50's and he had received irradiation therapy and underwent partial trans-sphenoidal hypophysectomy. His growth hormone values eventually declined while he had elevated insulin growth factor-1 (IGF-1) levels. The patient died from stroke 6 years after operation. Patient n. 2 is a 73-year-old female with a type II thoracoabdominal aortic aneurysm. She was operated for a pituitary adenoma in 1988. There were no clinical or biochemical signs of acromegaly. However, she had elevated serum values of IGF-1. The maximum diameter of the aneurysm was 60 mm. Because of comorbidity the patient has been followed at the outpatient clinic. The mechanism behind the combination of pituitary gland tumor and aneurysm is obscure. One of our patients had classical acromegaly. Growth hormone decreased over the years, while his IGF-1 values were normal or elevated. The other patient had increased levels of IGF-1 without typical acromegaly. This might indicate that IGF-1 could play a role in the development of aneurysm in patients with pituitary tumor. This combination of diagnoses should be kept in mind when dealing with patients having aneurysmal disease.

Evaluation of different types of alginate microcapsules as bioreactors for producing endostatin.

The use of nonautologous cell lines producing a therapeutic substance encapsulated within alginate microcapsules could be an alternative way of treating different diseases in a cost-effective way. Malignant brain tumors have been proposed to be treated locally using engineered cells secreting proteins with therapeutic potential encapsulated within alginate microcapsules. Optimization of the alginate capsule bioreactors is needed before this treatment can be a reality. Recently, we have demonstrated that alginate-poly-L-lysine microcapsules made with high-G alginate and a gelled core disintegrated as cells proliferated. In this study we examined the growth and endostatin secretion of 293-EBNA (293 endo) cells encapsulated in six different alginate microcapsules made with native high-G alginate or enzymatically tailored alginate. Stability studies using an osmotic pressure test showed that alginate-poly-L-lysine-alginate microcapsules made with enzymatically tailored alginate was mechanically stronger than alginate capsules made with native high-G alginate. Growth studies showed that the proliferation of 293 endo cells was diminished in microcapsules made with enzymatically tailored alginate and gelled in a barium solution. Secretion of endostatin was detected in lower amounts from the enzymatically tailored alginate microcapsules compared with the native alginate microcapsules. The stability of the alginate microcapsules diminished as the 293 endo cells grew inside the capsules, while empty alginate microcapsules remained stable. By using microcapsules made of fluorescenamine-labeled alginate it was clearly visualized that cells perforated the alginate microcapsules as they grew, destroying the alginate network. Soluble fluorescence-labeled alginate was taken up by the 293 endo cells, while alginate was not detected in live spheroids within fluorescence-labeled alginate microcapsules. Despite that increased stability was achieved by using enzymatically tailored alginate, the cell proliferation destroyed the alginate microcapsules with time. It is therefore necessary to use cell lines that have properties more suited for alginate encapsulation before this technology can be used for therapy.

Alginate-polylysine-alginate microcapsules: effect of size reduction on capsule properties.

Alginate-polylysine-alginate capsules containing insulin-producing cells have been used as a bio-artificial pancreas in the treatment of diabetes mellitus. In a search for microcapsules with improved diffusion characteristics, a high voltage system was developed that produces 250,000 beads/min with a diameter of 160 microm +/- 3-5%. The diameter of the beads could be varied between 160-700 microm depending on the needle diameter and construction, the voltage, the distance between the electrodes and the flow of alginate solution. Ca-alginate beads with diameters of 200 and 500 microm were produced by the high voltage electrostatic system. The 200 microm beads were sensitive to poly-L-lysine (PLL) exposure and had to be washed in ion-free solution to avoid collapse. The 200 microm beads swelled more than the 500 microm beads in the washing and PLL treatment. Also, the porosity of the capsules changed with size, but capsules impermeable to tumour necrosis factor (TNF) could be made by exchanging PLL with poly-D-lysine (PDL) for the 500 microm beads. The 200 microm beads were impermeable to IgG after PLL exposure. Islets of Langerhans were encapsulated in alginate-PLL-alginate capsules and evaluated by measuring protruding islets and insulin production. Islets in microcapsules made by the high voltage electrostatic system did not function differently from islets in larger microcapsules made by an air jet system. In conclusion, alginate capsules made by a high voltage electrostatic system enable large-scale production of small capsules with a narrow size distribution that can meet the functional properties of larger capsules by small changes in the encapsulation procedure.

Poly-L-Lysine induces fibrosis on alginate microcapsules via the induction of cytokines.

Alginate-poly-L-lysine (PLL) microcapsules can be used for transplantation of insulin-producing cells for treatment of type I diabetes. In this work we wanted to study the inflammatory reactions against implanted microcapsules due to PLL. We have seen that by reducing the PLL layer, less overgrowth of the capsule is obtained. By incubating different cell types with PLL and afterwards measuring cell viability with MTT, we found massive cell death at concentrations of PLL higher than 10 microg/ml. Staining with annexin V and propidium iodide showed that PLL induced necrosis but not apoptosis. The proinflammatory cytokine, tumor necrosis factor (TNF), was detected in supernatants from monocytes stimulated with PLL. The TNF response was partly inhibited with antibodies against CD14, which is a well-known receptor for lipopolysaccharide (LPS). Bactericidal permeability increasing protein (BPI) and a lipid A analogue (B-975), which both inhibit LPS, did not inhibit PLL from stimulating monocytes to TNF production. This indicates that PLL and LPS bind to different sites on monocytes, but because they both are inhibited by a p38 MAP kinase inhibitor, they seem to have a common element in the signal transducing pathway. These results suggest that PLL may provoke inflammatory responses either directly or indirectly through its necrosis-inducing abilities. By combining soluble PLL and alginate both the toxic and TNF-inducing effects of PLL were reduced. The implications of these data are to use alginate microcapsules with low amounts of PLL for transplantation purposes.

Transplantation of alginate microcapsules with proliferating cells in mice: capsular overgrowth and survival of encapsulated cells of mice and human origin.

Alginate microcapsules may be used to encapsulate therapeutic cells and, thereby, to protect them from the host immune system. Both the biomaterial, as well as the therapeutic cells, may give rise to immunological reactions. We have developed methods that are useful in the study of capsule biocompatibility, as well as reactions against the grafts. These imply investigation of the survival of the encapsulated cells as well as fibrotic reactions against the microcapsules. Studies were performed in Balb/c mice with empty alginate-PLL-alginate microcapsules as well as microcapsules containing cells of human or mouse origin. Confocal laser scanning microscopy (CLSM) was used to visualize live and dead cells within the microcapsules and to define some of the cells involved in the fibrotic reaction against the microcapsules. In both grafts, live cells were detected seven days after transplantation. Minor fibrotic reactions were found against empty alginate-PLL-alginate microcapsules and to microcapsules containing mouse cells. An extensive fibrotic reaction was found one week after transplantation against microcapsules containing human cells, and the secretion of therapeutic protein endostatin had ceased. Fibroblasts and macrophages were involved in the fibrotic reaction against the xenograft.

Soluble tumor necrosis factor receptors in sera from patients with insulin-dependent diabetes mellitus: relations to duration and complications of disease.

Concentrations of soluble receptors for tumor necrosis factor (p55 and p75) strongly correlate with clinical stage and progression of infectious diseases, and may be useful in monitoring autoimmune diseases. However, the role of soluble TNF receptors in insulin-dependent diabetes mellitus (type 1 DM) is not clear. We have compared levels of p55 and p75 in sera from different groups of type 1 DM patients. Group 1: 18 patients with type 1 DM duration from 1/2 to 3 years, group 2: 17 patients with type 1 DM duration of more than 10 years, and less than 20 microg/min excretion of albumin in urine, group 3: 24 patients with type 1 DM for more than 10 years and albumin excretion in urine higher than 20 mg/min. Sera from 24 healthy blood donors constituted a control group. We found that patients in group 1 and 2 had lower p55 levels than among controls (20% and 16.7%, respectively, both P < 0.01). Serum levels of p75 did not differ between the groups. Both p55 and p75 increased with severity of type 1 DM complications (P < 0.00001). These results indicate that type 1 DM without complications is associated with lower serum levels of p55 than in healthy controls, and that type 1 DM complications increase the p55 and p75 levels. In addition, the results suggest that increased serum levels of p55 and p75 in type 1 DM patients may be early markers of type 1 DM complications.