In vivo toxicity and biodistribution of intraperitoneal and intravenous poly-L-lysine and poly-L-lysine/poly-L-glutamate in rats.

The combination of two differently charged polypeptides, poly-L-lysine (PL) and poly-L-glutamate (PG), has shown excellent postsurgical antiadhesive properties. However, the high molecular, positively charged PL is toxic in high doses, proposed as lysis of red blood cells. This study aims to elucidate the in vivo toxicity and biodistribution of PL and complex bound PLPG comparing intravenous and intraperitoneal administration. Fifty-six Sprague-Dawley rats were used in a model with repeated blood samples within 30 min examining blood gases and blood smears. Similarly, FITC labelled PL were used to track bio distribution and clearance of PL, given as single dose and complex bound to PG after intravenous and intraperitoneal administration. Tissue for histology and immunohistochemistry was collected. Blood gases and blood smears as well as histology points to a toxic effect of high dose PL given intravenously but not after intraperitoneal administration. The toxic effect is exerted through endothelial disruption and subsequent bleeding in the lungs, provoking sanguineous lung edema. FITC-labelled PL experiments reveal a rapid clearance with differences between routes and complex binding. This study advocates a new theory of the toxic effects in vivo of high molecular PL. PLPG complex is safe to use as antiadhesive prevention based on this toxicity study given that PL is always intraperitoneally administered in combination with PG and that the dose is adequate.

Polysaccharide-K (PSK) in cancer--old story, new possibilities?

Polysaccharide-K (PSK, Krestin) is one of the most commonly used medicinal mushroom extracts with a long history as an additive in cancer therapy in Asia, especially in Japan. PSK has a documented anti-tumor activity both in vitro and in vitro, in various types of cancers, including colorectal, gastric, breast, liver, pancreatic, and lung cancer. Despite PSK having been studied for about 40 years as an immune modulator and biological response modifier, the mechanisms of action by PSK have not yet been clearly and completely elucidated. This review aims to provide an up-to-date account for the effects of PSK in cancer with the hope of thereby providing an increased understanding of the molecular mechanisms of PSK and also its potential as an additive in modern cancer therapy.

Molecular weight distribution of soluble fiber fractions and short chain fatty acids in ileal digesta of growing pigs.

The effect of dietary fiber source on molecular weight (MW) distribution of soluble fiber fractions and short chain fatty acids (SCFA) in ileal digesta of 7 post valve T-cecum (PVTC) cannulated growing pigs was studied. Pigs were fed semisynthetic diets with sugar beet (Beta vulgaris) pulp (SBP) or chicory (Cichorium intybus) forage (CFO) as fiber sources of which the soluble nonstarch polysaccharide (NSP) fraction originated mainly from pectin. Three MW intervals were selected-large MW (MWL): 10,000,000 to 1,000,000 g/mol, medium MW (MWM): 1,000,000 to 200,000 g/mol, and small MW (MWS): 200,000 to 10,000 g/mol-and the relative distribution (% of total) of molecules in each interval was calculated. The MWM fraction was higher (P < 0.05) in ileal digesta of pigs fed diet SBP and the MWS fraction was higher (P < 0.05) in ileal digesta of pigs fed diet CFO. The mole/100 mole of propionic acid (HPr) was higher (P < 0.010) in pigs fed diet SBP whereas pigs fed diet CFO had higher (P < 0.010) mole/100 mole of acetic acid (HAc). The proportion of the MWL and MWM fractions in ileal digesta were negatively correlated to HAc (r = -0.52, P = 0.05, and r = -0.62, P = 0.02, respectively). The proportion of MWM in ileal digesta was positively correlated to HPr (r = 0.83; P = 0.001) whereas MWS and HPr were negatively correlated (r = -0.76; P = 0.002). In conclusion, the bacterial degradation of the soluble NSP fraction is selective and MW distribution may explain differences in SCFA production.

Perioperative nutrition in elective gastrointestinal surgery--potential for improvement?

Nutritional concern is one of the most important issues to be addressed in the perioperative care given to gastrointestinal patients. Not at least, malnutrition may be detrimental and relate to postoperative morbidity. Perioperative nutritional management, integrated with other modern perioperative care policies, allows the establishment of multimodal strategies with an attempt to optimize the patients' course of disease. The present review evaluates available data regarding pre- and postoperative nutrition, nutritional supplements, including immunonutrition, and their clinical role. It is to be concluded that pre- and postoperative prolonged fasting has no routine role in management. Instead, for example, early postoperative feeding administered perorally or enterally may reduce postoperative complications and length of hospital stay. There are also indications that perioperative immunonutrition may reduce postoperative infectious complications and length of hospital stay, though further studies in this field are needed.

Multimodal management - of value in fulminant acute pancreatitis?

BACKGROUND: The multiple organ dysfunction syndrome (MODS) is the major cause of morbidity and mortality associated with acute pancreatitis. Presently, therapy is merely organ supportive as no effective therapy against underlying causative pathophysiological mechanisms exists. AIMS: To evaluate the effect of treatment with a platelet-activating factor inhibitor (PAFI), a monoclonal antibody against platelet endothelial cell adhesion molecule 1 (PECAM-1-MAb) and an oxygen free radical scavenger (N-acetylcystein; NAC), alone or in combination, on systemic organ dysfunction in experimental acute pancreatitis. METHODS: Severe acute pancreatitis was induced in rats by the intraductal administration of taurodeoxycholate. Treatment was given after 1 or 3 h, and evaluations were performed 6 h after induction. Organ dysfunction was evaluated by means of endothelial integrity impairment expressed as endothelial barrier leakage index. RESULTS: Severe acute pancreatitis caused a significant impairment in endothelial integrity in all organs studied and decreased levels of protease inhibitors compared to controls. The endothelial barrier impairment was significantly ameliorated by all treatment modalities, either given early or later. Combinations of NAC and the PECAM-1-MAb or the PECAM-1-MAb and the PAFI were the only schedules to restore endothelial barrier integrity to normal levels in most of the organs studied. CONCLUSION: Combination therapy with NAC and PECAM-1-MAb and/or PAFI may offer effective, causative-directed supplements to organ-supportive therapy of MODS in severe acute pancreatitis.

Comparison of starch branching enzyme I and II from potato.

The in vitro activities of purified potato starch branching enzyme (SBE) I and II expressed in Escherichia coli were compared using several assay methods. With the starch-iodine method, it was found that SBE I was more active than SBE II on an amylose substrate, whereas SBE II was more active than SBE I on an amylopectin substrate. Both enzymes were stimulated by the presence of phosphate. On a substrate consisting of linear dextrins (chain length 8-200 glucose residues), no significant net increase in molecular mass was seen on gel-permeation chromatography after incubation with the enzymes. This indicates intrachain branching of the substrate. After debranching of the products, the majority of dextrins with a degree of polymerization (dp) greater than 60 were absent for SBE I and those with a dp greater than 70 for SBE II. To study the shorter chains, the debranched samples were also analysed by high-performance anion-exchange chromatography. The products of SBE I showed distinct populations at dp 11-12 and dp 29-30, whereas SBE II products had one, broader, population with a peak at dp 13-14. An accumulation of dp 6-7 chains was seen with both isoforms.

Quorum sensing in the plant pathogen Erwinia carotovora subsp. carotovora: the role of expR(Ecc).

The production of the main virulence determinants of the plant pathogen Erwinia carotovora subsp. carotovora, the extracellular cell wall-degrading enzymes, is partly controlled by the diffusible signal molecule N-(3-oxohexanoyl)-L-homoserine lactone (OHHL). OHHL is synthesized by the product of the expI/carI gene. Linked to expI we found a gene encoding a putative transcriptional regulator of the LuxR-family. This gene, expR(Ecc), is transcribed convergently to the expI gene and the two open reading frames are partially overlapping. The ExpR(Ecc) protein showed extensive amino acid sequence similarity to the repressor EsaR from Pantoea stewartii subsp. stewartii (formerly Erwinia stewartii subsp. stewartii) and to the ExpR(Ech) protein of Erwinia chrysanthemi. Inactivation of the E. carotovora subsp. carotovora expR(Ecc) gene caused no decrease in virulence or production of virulence determinants in vitro. In contrast, there was a slight increase in the maceration capacity of the mutant strain. The effects of ExpR(Ecc) were probably mediated by changes in OHHL levels. Inactivation of expR(Ecc) resulted in increased OHHL levels during early logarithmic growth. In addition, overexpression of expR(Ecc) caused a clear decrease in the production of virulence determinants and part of this effect was likely to be caused by OHHL binding to ExpR(Ecc). ExpR(Ecc) did not appear to exhibit transcriptional regulation of expI, but the effect on OHHL was apparently due to other mechanisms.

The response regulator expM is essential for the virulence of Erwinia carotovora subsp. carotovora and acts negatively on the sigma factor RpoS (sigma s).

The main virulence factors of Erwinia carotovora subsp. carotovora, the secreted, extracellular cell-wall-degrading enzymes, are controlled by several regulatory mechanisms. We have isolated transposon mutants with reduced virulence on tobacco. One of these mutants, with a mutation in a gene designated expM, was characterized in this study. This mutant produces slightly reduced amounts of extracellular enzymes in vitro and the secretion of the enzymes is also affected. The expM wild-type allele was cloned together with an upstream gene, designated expL, that has an unknown function. The expM gene was sequenced and found to encode a protein with similarity to the RssB/SprE protein of Escherichia coli and the MviA protein of Salmonella typhimurium. These proteins belong to a new type of two-component response regulators that negatively regulate the stability of the Sigma factor RpoS (sigma s) at the protein level. The results of this study suggest that ExpM has a similar function in E. carotovora subsp. carotovora. We also provide evidence that the overproduction of RpoS in the expM mutant is an important factor for the reduced virulence phenotype and that it partly causes the observed phenotype seen in vitro. However, an expM/rpoS double mutant is still affected in secretion of extracellular enzymes, suggesting that ExpM in addition to RpoS also acts on other targets.

The influence of supplements of selenite, selenate and selenium yeast on the selenium status of dairy heifers.

The aim of the study was to define possible differences between selenite, selenate and selenium yeast on various aspects of selenium status in growing cattle. Twenty-four Swedish Red and White dairy heifers were fed no supplementary selenium for 6 months. The basic diet contained 0.026 mg selenium/kg feed dry matter (DM). After the depletion period the animals were divided into 4 groups; group I-III received 2 mg additional selenium daily as sodium selenite, sodium selenate, and a selenium yeast product, respectively. Group IV, the control group, received no additional selenium. The total dietary selenium content for groups I-III during the supplementation period was 0.25 mg/kg DM. After the depletion period the mean concentration of selenium in blood (640 nmol/l) and plasma (299 nmol/l) and the activity of GSH-Px in erythrocytes (610 mukat/l) were marginal, but after 3 months of supplementation they were adequate in all 3 groups. The concentration of selenium in blood and plasma was significantly higher in group III than in groups I and II, but there was no significant difference between groups I and II. The activity of GSH-Px in erythrocytes did not differ between any of the supplemented groups. The animals in the control group had significantly lower concentrations of selenium in blood and plasma and lower activities of GSH-Px in erythrocytes than those in the supplemented groups. The activity of GSH-Px in platelets was also increased by the increased selenium intake. There was no difference in the concentration of triiodothyronine (T3) between any of the groups, but the concentration of thyroxine (T4) was significantly higher in the unsupplemented control group.

The ineffectiveness of cyclical oral clodronate on bone mineral density in glucocorticoid-treated patients with giant-cell arteritis.

OBJECTIVES AND DESIGN: The aim of the present study was to determine whether cyclic oral administration of clodronate, a bisphosphonate, every second month prevents rapid bone loss during the first year of glucocorticoid treatment in patients with giant-cell arteritis (GCA). The trial was designed as a prospective double blind study, assessing total body mineral content (BMC) and bone mineral density (BMD) using DXA technique. Supplementation of calcium was given to both groups of patients. SETTING: The outpatient clinics of the rheumatic and infectious diseases of Sahlgren University Hospital of the city of Göteborg on the west coast of Sweden. SUBJECTS: Twenty-seven patients with confirmed GCA were consecutively included during a 15-month period. RESULTS: An early influence on bone turnover was found with a temporary decrease in BMC after six months of glucocorticoid treatment, which was normalized after 12 months in both study groups. No significant differences between the patients given clodronate and calcium and the controls, who got supplementation with calcium alone, was observed at any assessment point. However, there was a significant and prolonged depression of the osteocalcin levels in the clodronate-treated patients. CONCLUSIONS: Oral administration of clodronate in a moderately high dose given cyclically every other month had no additive effect on BMD compared with calcium supplementation alone during the first year of glucocorticoid treatment. A larger material might have revealed some differences between the categories. In most patients with GCA, however, the BMD seems to recover after one year of glucocorticoid treatment, provided there is good control of the inflammation and patients are kept physically active. It needs to be elucidated whether there are subsets of patients who might benefit from bone sparing agents: women near menopause with a high turnover rate of bone, individuals who have low BMD from the start of glucocorticoid treatment or patients requiring high doses of glucocorticoids during a long period of time.

Total dietary fiber determined as neutral sugar residues, uronic acid residues, and Klason lignin (the Uppsala method): collaborative study.

A joint AOAC/American Association of Cereal Chemists (AACC) collaborative study was conducted to determine by the Uppsala method the dietary fiber content and its composition in various foods. The method includes preparation of a residue by treatment with thermostable alpha-amylase and amyloglucosidase and then ethanol precipitation of solubilized dietary fiber components while leaving low-molecular weight carbohydrates in solution. After acid hydrolysis of residue, neutral polysaccharide residues are determined as alditol acetates by gas-liquid chromatography, uronic acid residues are determined by colorimetry, and ash-free acid-insoluble residue (Klason lignin) is determined gravimetrically. Total dietary fiber, including enzyme-resistant starch, is calculated as the sum of nonstarch polysaccharide residues and Klason lignin. Nine laboratories completed the study, analyzing in duplicate 8 unknown dried products that included 4 cereal products, green peas, potato fiber, carrots, and apples. Total dietary fiber contents of products tested ranged from 4.6 to 84.3%, with an average RSDR value of 8.4% (range, 4.8-11.1%). Total neutral polysaccharide residues ranged from 3.8 to 64.1%, with an average RSDR value of 7.5% (range, 5.4-10.5%). Individual neutral sugars (rhamnose, arabinose, xylose, mannose, galactose, and glucose) and uronic acid residues present at more than 1% generally had good RSDR values (3.3-22.8%), whereas, as expected for Klason lignin, only the wheat bran sample with a high content (16%) had an excellent RSDR value (5.0%). The gas chromatographic-colorimetric-gravimetric method (Uppsala method) for determination of total dietary fiber (as neutral sugar residues, uronic acid residues, and Klason lignin) has been adopted first action by AOAC INTERNATIONAL.

Inhibition of bacterial translocation in obstructive jaundice by muramyl tripeptide phosphatidylethanolamine in the rat.

Obstructive jaundice is frequently associated with septic complications and enteric bacteria have been isolated from both the infectious focus and bile in jaundiced patients. The present study aimed to evaluate bacterial translocation and the influence of a macrophage-stimulant (muramyl tripeptide phosphatidylethanolamine) on bacterial translocation in obstructive jaundice. Male Sprague-Dawley rats were subjected to sham operation (n = 10) or common bile-duct ligation and transection (n = 35). Two weeks later, jaundiced animals received either physiological saline (n = 15), muramyl tripeptide phosphatidylethanolamine liposomes (n = 10) or placebo (empty) liposomes (n = 10) orally, while sham-operated rats received physiological saline, 48 h prior to evaluation of enteric bacterial translocation. Blood, bile and caecal contents were collected and cultured aerobically and anaerobically, as were tissue samples from the liver, spleen and mesenteric lymph nodes. Positive mesenteric lymph node cultures in animals with jaundice + saline (7/15; 47%) and jaundice + placebo liposomes (4/10; 40%) significantly differed (p < 0.05) from sham-operated animals (1/10; 10%) and muramyl tripeptide phosphatidylethanolamine treated animals (0/10). Caecal counts (CFU/g) of Escherichia coli, Lactobacilli and aerobic and microaerobic bacteria did not differ statistically among the groups, although the number of E. coli tended to be higher in jaundiced animals. Thus, liposomal muramyl tripeptide phosphatidylethanolamine inhibits bacterial translocation, probably by activating mucosal macrophages and enhancing reticuloendothelial system function in rats with biliary obstruction.

Role of topical phospholipids in the prophylaxis of silicone elastomer-associated infection in the abdominal cavity.

The present study evaluated the influence of phospholipids (phosphatidyl choline and phosphatidyl inositol) on the prevention of abdominal biomaterial-associated infection. Phospholipid-impregnated silicone elastomer (SE) fragments were either intraperitoneally implanted in rats or immersed in serum for 0, 4, and 14 days, and 3 x 10(9) cfu of 3H-labeled, live Escherichia coli were added in the peritoneal cavity or in vitro incubation medium. Three hours after incubation, the adherence of bacteria significantly decreased to phospholipid-impregnated SE fragments, which had been immersed/implanted for 0 and 4 days. However, the number of adhering bacteria did not differ between the impregnated and unimpregnated SE fragments after 14 days of immersion/implantation. A significantly lower number of adhering bacteria was noted on all unimpregnated SE fragments when phospholipid was supplemented in the peritoneal cavity or in vivo medium, compared with fragments with no supplement. The rate of bacterial DNA synthesis decreased significantly after incubation with phospholipid 2 h or more. Phospholipids did not further influence peritoneal morphology. Thus topical administration of phospholipids by impregnation to the surface of SE fragments or supplement in the incubation medium prevented bacterial adherence onto the SE fragments. This implies that the use of phospholipids might be a mode of preventing biomaterial-associated infections.

Phospholipid impregnation of abdominal rubber drains: resistance to bacterial adherence but no effect on drain-induced bacterial translocation.

In order to evaluate the effect of surface modification of biomaterials on bacterial adherence and bacterial translocation after intraperitoneal biomaterial implantation, phosphatidylcholine- or phosphatidylinositol-impregnated rubber drain pieces, which had been intraperitoneally implanted in the rat for 2 and 7 days, or unimplanted, were incubated in vitro with 3H-labelled Escherichia coli and Enterobacter cloacae. As compared with unimpregnated pieces, the adherence of bacteria significantly decreased to phosphatidylcholine- and phosphatidylinositol-impregnated rubber drain pieces that were either unimplanted or implanted for 2 days, but not for 7 days. The supplementation of albumin in the medium reduced the adherence of bacteria to the unimplanted, unimpregnated drain pieces, but did not further decrease adherence of bacteria to the unimplanted, phospholipid-impregnated brain pieces. Bacterial growth was inhibited after incubation in nutrient broth supplemented with phospholipids. The incidence of enteric bacterial translocation induced by intraperitoneal drain implantation did not differ between phospholipid-impregnated and unimpregnated drain pieces. Scanning electron microscopy revealed a large amount of biofilm and fibrous deposition on the surface of the implanted, phospholipid-impregnated rubber drain pieces. Thus, phospholipid impregnation of rubber drains reduces bacterial adherence and inhibits bacterial growth, without influencing the incidence of bacterial translocation.

Intraperitoneal 5-fluorouracil in the management of colorectal liver cancer.

Twenty-five patients with colorectal liver metastases had a subcutaneous portal connection with a peritoneal catheter implanted for the intraperitoneal (i.p.) administration of 5-fluorouracil (5-FU). In five patients, the malignant disease rapidly progressed and the implanted catheter system was never used. Among the remaining 20 patients, seven patients had i.p. 5-FU as adjuvant treatment following liver resection and 13 patients received palliative chemotherapy (5-FU) owing to unresectable liver metastases. 5-FU was administered on a regular basis every 4 to 6 weeks by continuous infusion of 1000 mg/day (approximately 15 mg/kg/day) for 5 days. In seven patients, i.p. chemotherapy was managed on an outpatient basis. In general, i.p. 5-FU treatment was well tolerated with only minor abdominal complaints during the initial treatments. No definite effect on survival has been noted. All patients (n = 13) receiving palliative i.p. 5-FU died after a median of 4 (range 1.5-18) months. Two patients receiving adjuvant chemotherapy died owing to recurrence after 20 and 23 months, while five patients are alive, two with recurrent disease and three without, after 14-35 months.

Microdontin A and B: Two New Aloin Derivatives from Aloe microdonta.

The leaf juice of ALOE MICRODONTA Chiov. is used in Somali traditional medicine as a remedy for jaundice and for topical treatment of skin diseases. Mucilage was precipitated from the fresh juice by addition of ethanol and the supernatant chromatographed on Amberlite XAD-2 to yield a fraction containing anthraquinone derivatives. Flash chromatography on silica gel followed by preparative TLC yielded aloin A and a new compound. Spectral data (mass, (1)H- and (13)C-NMR) identified this compound as a mixture of aloin A and B where the glucose of both compounds is esterified with 4-hydroxycinnamic acid at the 6'-position. The two compounds were denoted as microdontin A and B, respectively.

Acetic acid-induced colitis in the rat: a reproducible experimental model for acute ulcerative colitis.

There exists no ideal model for experimental ulcerative colitis in common laboratory animals. Therefore, we tried in the present study to establish a reproducible model for inducing colitis in rats by using acetic acid. A blind loop of the colon including the cecum, ascending colon and part of the transverse colon, was brought out through two colostomies. After mechanical washing with warm normal saline, acetic acid was instilled at different doses (4, 6 and 8%) for different exposure times (10, 15, 20, 25 and 30 s). The excluded colon was examined by light microscopy on the 1st, 2nd, 3rd, 4th, 7th and 14th days after operation and acetic acid instillation. We found that 4% acetic acid for 15 s produced a moderate, superficial colitis on the 1st day after operation, whereafter a uniform colitis evolved in all rats on the 4th day after operation. The developed colitis showed morphological similarities with human ulcerative colitis. Signs of healing and regeneration of the mucosa were seen on the 7th day, and the mucosa became almost normal at the 14th day after operation. 6 or 8% acetic acid solution or exposure times exceeding 15 s resulted in severe, deep colitis with a concomitant high mortality rate. In contrast, at exposure times less than 15 s, acetic acid induced only mild superficial colitis. We conclude that by using 4% acetic acid for 15 s in the excluded colon a uniform and reproducible colitis pathologically resembling human ulcerative colitis could be achieved. Furthermore, no mortality was encountered and the general health of the rats was similar to that of the controls.(ABSTRACT TRUNCATED AT 250 WORDS)

T-cadinol: a pharmacologically active constituent of scented myrrh: introductory pharmacological characterization and high field 1H- and 13C-NMR data.

Fractionation of an ethyl acetate extract of scented myrrh (resin of Commiphora guidottii Chiov., Burseraceae), using the guinea pig ileum test to monitor pharmacological activity, resulted in isolation of the sesquiterpene (+)-T-cadinol. High field NMR spectroscopy yielded new detailed 1H- and 13C-NMR data for the compound. T-cadinol was shown to have a concentration-dependent smooth muscle relaxing effect on the isolated guinea pig ileum and a dose-dependent inhibitory effect on cholera toxin-induced intestinal hypersecretion in mice.

Glucose tolerance and insulin secretion in experimental peritonitis in the rat.

The changes in the regulation of insulin secretion that accompany sepsis are yet to be fully established. We therefore examined insulin secretion both in vivo and in vitro in 2 different models of peritonitis/sepsis in the rat. Sepsis was induced by intraperitoneal injection of Escherichia coli either alone or together with bile. Following sepsis induction, an initial hyperglycemia developed. This hyperglycemia was transient and had vanished after 3 h (coli group) or 9 h (bile group). However, after 24 h, a second phase of hyperglycemia developed in both groups. The glucose elimination rate after intravenous glucose injection (0.5 g/kg) at 4 and 10 h after peritonitis/sepsis induction was retarded and the hyperglycemia that occurred during intravenous glucose infusion (10 mg/min for 30 min) was exaggerated. This is consistent with a reduced glucose uptake. Simultaneously, the plasma insulin responses to glucose were markedly exaggerated. This could be due to a true potentiated insulin secretion or simply to an adaptation to the hyperglycemia. However, also during intravenous arginine infusion (7 mg/min) at 4 h after peritonitis/sepsis induction, the plasma insulin responses were markedly exaggerated. Since only a slight change in plasma glucose occurred during this challenge, the results suggest that sepsis is accompanied by a true hypersecretion of insulin. To verify whether this is directly or indirectly mediated, pancreatic islets were isolated from peritonitis/sepsis animals at 4 h after disease induction and incubated for 45 min in a KRB medium supplemented with different concentrations of glucose. The subsequent insulin secretion was the same in islets from the septic animals as in controls. Hence, our results show that experimental peritonitis/sepsis in the rat is accompanied by (1) glucose intolerance and (2) a true hypersecretion of insulin which is indirectly mediated.