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S Bengmark

Publications and source records attributed to S Bengmark.

At least 19 recordsLinked to original sources
PubMed2001

Sodium polyacrylate potentiates the anti-adhesion effect of a cellulose-derived polymer.

Available methods for postoperative adhesion prevention are insufficient. A previous study demonstrated that LM-200, a bioadhesive cellulose derivative was effective in reducing adhesions. Increasing the viscosity of a polymer solution enhances the tissue separating properties. Theoretically, a combination of sodium polyacrylate (PA) and LM-200 would give more viscous solutions than LM-200 alone, and thus be more efficacious. Therefore the efficacy of various combinations of LM-200 and PA was investigated. A lesion was created in the peritoneum of mice. The solutions to be tested, or saline, were given intraperitoneally. One week post-operatively, adhesion formation was quantified and expressed as a percentage of the original lesion covered with adhesions. PA (0.01 and 0.03 wt%) given separately did not differ in adhesion reducing effect from LM-200 (p = 0.3710 and 0.3481) but PA (0.1 wt%) resulted in significantly less adhesion formation (p = 0.0004). The effect of LM-200 increased significantly when adding PA (0.01 wt%) (p = 0.0007) or PA (0.03 wt%) (p < 0.0001). When adding PA (0.1 wt%) the effect was even more pronounced (p < 0.0001). The combination of a bioadhesive cellulose derivative and the polymer PA, was effective in reducing postoperative adhesion formation and a dose-dependent increase in efficacy was obtained compared to using the two components separately.

Abdomen↗
PubMed2001

Prevention of adhesions by surfactants and cellulose derivatives in mice.

OBJECTIVE: To evaluate the efficacy of hydrophobically modified ethyl (hydroxyethyl) cellulose (cellulose), sodium hyaluronate (hyaluronate) and phosphatidylglycerol, in the reduction of adhesion formation. DESIGN: Controlled study. SETTING: Experimental academic unit, Sweden. MATERIAL: NMRI mice. Solutions: (1) cellulose, (2) hyaluronate, (3) phosphatidylglycerol, (4) phosphatidylglycerol and cellulose, and (5) phosphatidylglycerol, cellulose and hyaluronate. INTERVENTIONS: A standard lesion was created in the parietal peritoneum in mice. One of the viscous solutions to be tested, or saline, was given intraperitoneally. MAIN OUTCOME MEASURES: Amount of adhesions found one week postoperatively. RESULTS: Cellulose; phosphatidylglycerol and cellulose; and phosphatidylglycerol, cellulose and hyaluronate all significantly reduced the amount of adhesions (p=0.0002, p=0.002, p < 0.0001), as did the hyaluronate alone (p < 0.05). Phosphatidylglycerol alone did not reduce the amount of adhesions. Combining cellulose with phosphatidylglycerol, or with hyaluronate, did not improve efficacy. CONCLUSION: Cellulose and hyaluronate were effective in reducing the formation of adhesions. Combining cellulose with hyaluronate or phosphatidylglycerol or both did not improve efficacy.

Animals↗
PubMed2001

Lactobacillus plantarum reduces infection of pancreatic necrosis in experimental acute pancreatitis.

BACKGROUND: Infection is the commonest cause of death in acute pancreatitis. Early reduction of commensal flora (particularly Lactobacillus species) and, at the same time, overgrowth of Enterobacteriaceae, especially Escherichia coli, have recently been described during acute pancreatitis. Lactobacillus plantarum has been shown to be effective in reducing the egress of endotoxin and microbial translocation in several experimental models such as chemically induced hepatitis and ulcerative colitis. AIM: The aim of the study was to determine whether L. plantarum 299v (Lp 299v) is capable of effectively reducing microbial translocation in experimental pancreatitis. METHODS: Acute pancreatitis was induced by isolation and ligation of the biliopancreatic duct in Lewis rats weighing 250-350 g. The animals were divided into 3 groups: group A, sham operation; group B, induction of pancreatitis and no further treatment, and group C, induction of pancreatitis + daily administration by gavage of a 5-ml/day suspension of Lp 299v at 0.5-1.0 x 10(9) bacteria/ml for 8 days, 4 days before and 4 days after induction of pancreatitis. All animals were sacrificed after 96 h. Histological studies and microbiological analyses were performed. RESULTS: At sacrifice, 40/55 animals showed signs of severe pancreatitis. Since acute pancreatitis was the specific disease investigated, only these animals were subjected to further study. In group B, we found pathogenic micro-organisms in the mesenteric lymph nodes in 14/20 animals and in the pancreatic tissue in 10/20. The bacterial flora consisted predominantly of E. coli, Enterococcus faecalis, Pseudomonas and Proteus species. In contrast, when the animals were kept under an 'umbrella' of Lp 299v, growth of E. faecalis or E. coli were detected only in 4/20 mesenteric lymph node cultures and in 3/20 pancreatic tissue cultures. CONCLUSIONS: Lp 299v is effective in reducing microbial translocation in experimental pancreatitis. Treatment with probiotic bacteria seems to be a promising alternative to antibiotic therapy.

Acute Disease↗
PubMed2000

Colonic food: pre- and probiotics.

The colonic mucosa is unable to nourish itself from the blood. Instead, its nutritive demand must be met from the lumen, where different nutrients, short-chain fatty acids, amino acids, polyamines, growth factors, vitamins, and antioxidants are produced by a nonpathogenic (commensal, so-called "protective" probiotic) flora. The substrates for the production of nutrients are usually referred to as prebiotics, which consist mainly of ingested fibers and complex proteins (colonic food), but may also include necrotic mucosal cells, mucus, gastrointestinal (GI) secretions, and bacteria (as well as yeasts broken down by the bacteria). A characteristic common to all foods destined for the colon--colonic foods-is that no enzymes in the small intestine are capable of breaking them down. It is recommended that a minimum of 10% of ingested calories and about 20% of the food volume should be colonic food. The probiotic flora is today often found deficient, especially in industrialized nations. Studies have shown that Lactobacillus plantarum can preserve key nutrients, vitamins, and antioxidants; eliminate toxic components from food; protect food from decay; and eradicate pathogens such as Enterobacteriaceae, S. aureus, and enterococci from fermented food. In addition, it has demonstrated effectiveness over other bacteria in the metabolism of semiresistant oligofructans. L. plantarum-fermented oat given to healthy volunteers significantly reduces the gut content of potentially pathogenic microorganisms (PPMs).

Animals↗
PubMed2000

Probiotics and immune response.

Current evidence supports the concept that oral administration of probiotic lactobacilli may be therapeutic in preventing antibiotic-associated diarrhea in children and in reestablishing normal flora in the gastrointestinal tract. Children with human immunodeficiency virus (HIV) infections may have episodes of diarrhea and frequently experience malabsorption associated with possible bacterial overgrowth; together these may interact to produce the growth abnormalities characteristic of this group. The overall objective of this investigation has been to determine whether oral administration of the probiotic Lactobacillus plantarum 299v could improve nutrient status and promote growth in children congenitally exposed to HIV. In addition, the possible beneficial effect of Lactobacillus plantarum 299v in modulating immune response was evaluated. In preliminary results described here, we report on the ability of Lactobacillus plantarum 299v to colonize children with HIV and to elicit specific systemic immune response after oral supplementation.

Child↗
PubMed1999

Gut microenvironment and immune function.

Overreaction of the acute phase response is responsible for the two major complications to surgery, sepsis and thrombosis, but also most likely for the leading sequela to surgery, adhesion formation. The gastrointestinal tract, especially the colon, is a major player in the acute phase response and responsible for important immune functions with important interactions between the commensal flora, mucosal cells and the mucosa/gut associated lymphoid tissues. These responses can effectively be modulated by enteral nutrition, provided it is properly composed and administered. There is increasing evidence that the important clinical effects sometimes observed in enteral nutrition are more related to immunostimulatory effects than to reduction in microbial translocation. It is suggested that in order to be effective enteral nutrition should be instituted if possible before the operation, but always at least immediately after. Furthermore, much supports that the formula given should contain what has been called colonic food, e.g. plant fibres, and have a low content of saturated fat. Use of antibiotics with deleterious effects on the commensal flora should also be limited as much as possible. Lack of compliance with these requests seems to explain the lack of consistency in clinical experience of enteral nutrition, when tried in connection with trauma and clinical surgery.

Acute-Phase Reaction↗
PubMed1999

Dearterialization of colorectal liver cancer: institutional experience.

BACKGROUND/AIMS: Preliminary clinical trials have suggested that dearterialization (interruption of arterial blood supply) is beneficial to patients with liver tumours. The aim of this report was to review the outcome of all patients undergoing dearterialization for colorectal liver metastases and to analyze whether refinement of the technique was followed by improvement in outcome. METHODS: Retrospective review of 57 patients undergoing temporary (16 h) dearterialization during 1972-1984 (n = 24) or repeated transient dearterialization (1-2 h once or twice daily) during 1985-1995 (n = 33). RESULTS: The median survival after start of treatment was 1.1 years, and the 5-year survival rate was 0%. There was no significant difference in survival between temporary and repeated transient dearterialization. Liver tumour volume and extrahepatic metastases varied negatively with survival. The temporary dearterialization procedure was followed by hepatic or intra-abdominal abscess formation in 6 patients (24%), leading to postoperative death in 2 patients (operative mortality 8%). Complications after repeated transient dearterialization were related mainly to technical problems with the occluder device. CONCLUSION: Although this was not a randomized study, it appears that dearterialization is of no benefit in colorectal liver cancer.

Catheterization↗
PubMed1998

Polymers that reduce intraperitoneal adhesion formation.

BACKGROUND: Viscous macromolecules and phospholipids have been shown to reduce postoperative adhesion formation. The ideal agent, or combination of agents, still remains to be identified. METHODS: The effect of hydrophobically modified ethyl (hydroxyethyl) cellulose (HM-EHEC) and polyquarternium-24 (LM-200), two cellulose-derived polymers, and of sphingomyelin, was examined in an animal model. Adhesions were induced in the parietal peritoneum in a standardized manner and quantity, and the morphology of adhesion formation was evaluated after 7 days. RESULTS: A significant reduction in adhesion formation was seen in animals receiving LM-200 (P=0.013) and HM-EHEC (P=0.012) as a short-term treatment compared with controls given saline, but not in animals receiving sphingomyelin (P=0.733). Additional effects were seen in the animals receiving LM-200 as a prolonged treatment (P< 0.001) compared with controls. There was no difference in the magnitude of the inflammatory response between the groups. CONCLUSION: These results suggest that hydrophobically modified polymers are efficient in reducing adhesions, without affecting the inflammatory response.

Animals↗
PubMed1997

Effect of oral supplementation of lactobacilli on bacterial translocation in acute liver injury induced by D-galactosamine.

BACKGROUND/AIM: Bacterial infections and sepsis are frequent complications of acute liver injury, with a high share in the mortality and morbidity of this condition. Bacterial translocation from the gut may play an important role in the high rate of infections observed. In this experiment the effect of different oral supplementation on bacterial translocation was evaluated in acute liver injury induced by D-galactosamine in the rat. METHODS: Rats were given oral supplements of lactulose, neomycin, Lactobacillus reuteri R2LC, and Lactobacillus plantarum DSM 9843 for 1 week. Liver injury was induced by intraperitoneal administration of 1.1 g/kg D-galactosamine. Twenty-four hours later, rats were sacrificed and liver enzymes and histology, intestinal bacterial count and microflora, intestinal mucosal histology, DNA and RNA content, bacterial translocation to blood, mesenteric lymph nodes, and liver, and serum endotoxin were studied or measured. RESULTS: Lactulose was highly effective in prevention of liver injury and bacterial translocation. Neomycin and Lactobacillus plantarum DSM 9843 showed a moderate effect in prevention of liver injury and bacterial translocation. Intestinal bacterial count and microflora were affected by different treatment modalities. No endotoxin concentration was found in any of the experimental groups. Both lactobacilli could significantly improve the mucosal proliferative state. CONCLUSIONS: Oral supplementation of lactulose with anti-endotoxin effect could successfully prevent the liver injury and the subsequent bacterial translocation in acute liver injury induced by administration of D-galactosamine in the rat. This effect was irrespective of the intestinal bacterial alteration or mucosal proliferative state.

Acute Disease↗
PubMed1996

Glutathione and phospholipid depletion of liver tumors after arterial ischemia.

Breakdown of membrane phospholipids is a causative event leading to irreversible cell injury after ischemia and reperfusion insults, which might be one mechanism leading to liver tumor cell death after repeated arterial ischemia as well. After 2 hr of hepatic dearterialization followed by 30 min of reperfusion tumor phospholipid was measured chromatographically, glutathione (GSH) analyzed by determining nonprotein sulfhydryl and activity of glutathione-S-transferase (GST) determined spectrophotometrically using 1-chloro-2,4-dinitrobenzene (CDNB) as the substrate. A transient, arterial ischemia for 2 hr induced a substantial decrease of phosphatidylserine (PS) and phosphatidylinosital (PI) compared with sham treatment (P < 0.01). Although phosphatidylcholine (PC) and phosphatidylethanolamine (PE) did not significantly decline after a single arterial ischemia for 2 hr, they dropped dramatically following repeated arterial ischemia for 2 hr during 5 days (P < 0.01 and P < 0.05 respectively). GSH was depleted in tumors after both a single (P < 0.01) and repeated arterial ischemia (P < 0.05) and GST was inactivated as well (P < 0.001). By contrast, neither liver phospholipid nor liver GSH or GST was significantly changed. Tumor growth was significantly retarded in rats subjected to repeated arterial ischemia compared with sham treatment (P < 0.01). Repeated arterial ischemia facilitated degradation of tumor membrane phospholipids and induced depletion of GSH and inactivation of GST without affecting the normal liver. Thus, ischemia/reperfusion induced depletion of membrane phospholipids and of GSH might represent two mechanisms by which repeated arterial ischemia led to tumor growth delay.

Animals↗
PubMed1996

Bacterial translocation in acute liver injury induced by D-galactosamine.

Acute liver injury is associated with a high rate of infectious and septic complications. Most of these infections are produced by gram negative enteric bacteria. We evaluated bacterial translocation, intestinal permeability, blood flow, portal pressure, and intestinal microflora after induction of liver injury and 70% liver resection in the rat. The rate of translocation to both portal and arterial blood was 100% at 24 hours and 50% at 48 hours after liver resection compared with 83% to portal vein and 50% to aortic blood at both time points after acute liver injury. Translocation to intraabdominal organs (liver, spleen, and mesenteric lymph nodes) was 100% in both groups at both 24 and 48 hours. The rate of translocation increased after liver injury at 48 hours with progression of the liver injury but was decreased in the 70% liver resection group with improvement of liver function. "Total aerobic" and "total anaerobic" bacterial counts in small intestine and cecum were not affected. Pulmonary, distal small intestine, and cecal blood flow were decreased in both groups, whereas blood flow in the proximal small intestine was unaffected. Portal pressure and flow were increased after 70% liver resection, but they were decreased in acute liver injury. After acute liver injury, permeability of both distal small intestine and cecum increased, but after liver resection only cecal permeability increased. The results of this experiment show that bacterial translocation occurs in experimental acute liver injury and that its dynamic, pattern and fate are different from that observed after liver resection, which is a reversible surgical model of liver insufficiency.

Analysis of Variance↗
PubMed1996

The effect of endotoxin and Lactobacillus pretreatment on peritoneal macrophage behavior in acute liver injury in rat.

The effect of endotoxin and Lactobacillus R2LC pretreatment in acute liver injury, induced by D-galactosamine was studied. Administration of D-galactosamine resulted in much higher luminescent activity than the control (49.24 mV vs 19.75 mV), while there was no change detected on the metabolic response to phorbol-12-myristate-13-acetate (PMA) stimulation in the calorimeter. Pretreatment of animals with intraperitoneal administration of heat-killed Lactobacillus resulted in higher oxygen free radical production (105.46 mV) and a much higher metabolic response to PMA in microcalorimeter (24.63 pW per cell vs 13.03 in the control). On the other hand pretreatment with endotoxin resulted in higher luminometric response to PMA compared to liver injury group (65.87 mV), and no response in the microcalorimeter at all. Phagocytic activity was decreased from 86 to 59% after administration of D-galactosamine, and was not significantly influenced by any of the pretreatment modalities. This experiment showed that pretreatment with Lactobacillus resulted in increased macrophage metabolic activity, while endotoxin pretreatment rendered the macrophages unresponsive to subsequent stimulation. These findings may explain why pretreatment with endotoxin is beneficial in acute liver injury induced by D-galactosamine, but not with gram-positive bacteria including Lactobacillus.

Animals↗