Endotoxin Production Research Articles

Relationship between endotoxin and prostaglandin (PGE 2 and PGFM) concentrations and ovarian function in dairy cows with puerperal endometritis

Blood concentrations of progesterone, 13,14-dihydro-15-keto-prostaglandin F2alpha (PGFM) and endotoxin, and uterine fluid concentrations of prostaglandin E 2 (PGE 2), PGFM and endotoxin were evaluated in 14 dairy cows with puerperal endometritis (mild ( n=6) and heavy ( n=8)). Endotoxin was measured using a quantitative kinetic assay. Cows with heavy endometritis had significantly higher concentrations of plasma PGFM ( P<0.01) and uterine fluid PGE 2 and endotoxin ( P<0.05) than cows with mild endometritis. Concentrations of PGFM in plasma and uterine fluid, of PGFM and PGE 2, and PGE 2 and endotoxin in uterine fluid were positively and significantly ( P<0.05) correlated. The presence of endotoxin in plasma was detected in one out of six mild and in eight out of eight heavy endometritis cows. Peak plasma endotoxin concentrations (0.08–9.14 endotoxin units/ml (EU/ml) were observed between 1 and 12 days postpartum (pp) and thereafter amounts generally remained below 0.1 EU/ml (last day of detection: Day 27 pp). Abnormal ovarian function was observed in six cows (four with prolonged anoestrus and two with long luteal phase after the first postpartum ovulation). Plasma endotoxin concentrations were detected in the anoestric cows. The results suggest that: (i) concentrations of uterine fluid endotoxin and PGE 2 and of plasma PGFM are related to the degree of endometritis; (ii) absorption of endotoxin from the uterus to the bloodstream occurs, mainly in heavy endometritis cows; and (iii) there is a relationship between uterine infection, endotoxin production and resumption of pp ovarian activity.

Effect of Chishao Chengqi decoction on endotoxin and TNF-α in patients with severe hepatic diseases

To observe the effect of Chishao Chengqi decoction (CCD) in treating severe hepatopathy and its influence on serum endotoxin(ET) and tumor necrosis factor a (TNF-α), in order to explore the possible mechanism of CCD in protecting liver cells and in preventing liver failure. Sixty patients suffering from hepatopathy were divided into the treated group and control group randomly, 30 in each group. They were treated with comprehensive treatment, including hepatocyte growth-promoting factors, thymosin, Transmetil and albumin. CCD was given to the treated group additionally. The therapeutic effects were observed and the changes of some biochemical criteria, including alanine transaminase (ALT), aspartate aminotransferase (AST), total bilirubin (TB), albumin (ALB) as well as such parameters as prothrombin activity (PTA), serum levels of ET and TNF-; were all detected respectively before treatment and after treatment. In the treated group, 8 patients was clinically cured after treatment, 11 were markedly alleviated, 7 improved and 4 remained unchanged, while in the control group, the respective numbers were 5,8,8 and 9. The total effective rate of the treated group was significantly better than that of the control group by(P<0. 05). ET and TNF-a levels in patients were significantly higher than the normal range before treatment, and they were lowered after treatment. Comparison of the effect between the two groups showed significant difference (P<0.05 ) , with that in the treated group better than that in the control group. CCD decoction could reduce the production and releasing of ET and TNF-α in severe hepatopathy patients, which might be one of its therapeutic mechanisms.

Biofilms: survival mechanisms of clinically relevant microorganisms.

Though biofilms were first described by Antonie van Leeuwenhoek, the theory describing the biofilm process was not developed until 1978. We now understand that biofilms are universal, occurring in aquatic and industrial water systems as well as a large number of environments and medical devices relevant for public health. Using tools such as the scanning electron microscope and, more recently, the confocal laser scanning microscope, biofilm researchers now understand that biofilms are not unstructured, homogeneous deposits of cells and accumulated slime, but complex communities of surface-associated cells enclosed in a polymer matrix containing open water channels. Further studies have shown that the biofilm phenotype can be described in terms of the genes expressed by biofilm-associated cells. Microorganisms growing in a biofilm are highly resistant to antimicrobial agents by one or more mechanisms. Biofilm-associated microorganisms have been shown to be associated with several human diseases, such as native valve endocarditis and cystic fibrosis, and to colonize a wide variety of medical devices. Though epidemiologic evidence points to biofilms as a source of several infectious diseases, the exact mechanisms by which biofilm-associated microorganisms elicit disease are poorly understood. Detachment of cells or cell aggregates, production of endotoxin, increased resistance to the host immune system, and provision of a niche for the generation of resistant organisms are all biofilm processes which could initiate the disease process. Effective strategies to prevent or control biofilms on medical devices must take into consideration the unique and tenacious nature of biofilms. Current intervention strategies are designed to prevent initial device colonization, minimize microbial cell attachment to the device, penetrate the biofilm matrix and kill the associated cells, or remove the device from the patient. In the future, treatments may be based on inhibition of genes involved in cell attachment and biofilm formation.

Effects of interleukin-18 on diaphragm muscle contraction on rats.

To evaluate the role of interleukin (IL)-18 in endotoxin-induced diaphragm muscle deterioration, we studied three treatment groups, namely, a saline+endotoxin group, an IL-18+endotoxin group and an IL-18 only group using Wistar rats. Five minutes after saline or IL-18 (0.25 microg) injection, E. coli endotoxin (30 mg/kg) was injected intraperitoneally. In the saline+endotoxin group, the force-frequency curves by ANOVA (p < 0.01), twitch tension (TT) and slope during contraction time (TT/CT) were significantly lower at 4 hours than those at 0 hours due to endotoxin (p < 0.01 and p < 0.05, respectively) and nitric oxide (NO) production had increased at 4 hours as shown by NADPH diaphorase staining. In the IL-18+endotoxin group, the decrement of the force-frequency curves in a higher frequency range (50-120 Hz), and the decrements of TT and TT/CT observed at 4 hours in the saline+endotoxin group were significantly prevented, and NO production was blocked at 4 hours. In the IL-18 only group, the force-frequency curves did not change except for fatigability, and NO production did not occur. It is suggested that IL-18 itself naturally blocks NO production, even when endotoxin coexists, resulting in the prevention of deterioration of diaphragm muscle contraction by endotoxin.

Surgical management of severe peritonitis

Despite all the efforts made in the areas of intensive care and surgery, severe peritonitis remains a feared condition that is associated with a high mortality rate. Severe abdominal infections are accompanied with a high level of endotoxin production, resulting in the so called systemic inflammatory response syndrome (SIRS), which is often complicated by multiple organ failure. The surgical eradication of the infectious focus is the most important prerequisite for a successful treatment. According to the severity of the local inflammation, different forms of abdominal lavage can be applied. We analysed patient characteristics and the clinical outcome of 180 patients with diffuse peritonitis, including 36 patients with more than 29 MPI-Points. The mean severity of peritonitis (n = 36) was 33 using the Mannheim Peritonitis Index (MPI). The hospital mortality rate was 58 % in this group.

Wastewater treatment sludge as a raw material for the production of bacillus thuringiensis based biopesticides

Seven wastewater sludges of different origins and types were used as an alternate culture medium for producing Bacillus thuringiensis variety kurstaki HD-1. The sludge samples were used under three different preparations: without pre-treatment, with acid treatment (hydrolysed sludge) and the supernatant obtained after centrifugation of the hydrolysed sludge. The sludge composition varied widely with origin and the type of sludge. Growth and sporulation were evaluated by the total viable cell count and spore count of the preparations. Growth, sporulation and endotoxin production were affected by the sludge origin. Hydrolysed sludge gave the highest viable cell and spore counts while the liquid phase (supernatant) gave the lowest. Non-hydrolysed primary sludge from Valcartier was unable to sustain bacterial growth because of its low pH. Bioassays were conducted against larvae of spruce budworm to evaluate entomotoxic potential of the preparations obtained. In general, sludge hydrolysis increased the entomotoxicity yields. Similar entomotoxicity was observed in Black Lake secondary sludge (4100 IU/μL) as that obtained in the reference soya medium (3800 IU/μL). The use of the sludge supernatant (liquid phase) was not recommended due to the low entomotoxic potential obtained.

Laminitis in Przewalski horses kept in a semireserve

Semireserves were created by the European Conservation Project for scientific research in preparation for reintroduction in the wilderness. They are defined as enclosures large enough to carry a group of Przewalski horses throughout the year without any additional feeding. The semireserve offers diverse opportunities for significant scientific research. As part of a general screening program, the hoof development in a group of Przewalski horses was investigated in the semireserve Schorfheide near Berlin. Since the foundation of this semireserve in 1992, veterinary treatment was not necessary with the exception of hoof trimming in two animals in 1993. However, major health problems were encountered in the spring of 1999, when three other mares showed signs of laminitis. The initial diagnosis by the authors and the local veterinary surgeon based on observation of behaviour, gait, stance, walk and trot of three mares whose initial weights were higher than those of the healthy mares. The initial diagnosis was confirmed by palpation and the occurrence of very deep horn rings on all hooves and a laminitic horn ring on the right front hoof of one mare. An adequate laminitic therapy was not possible under the conditions of a semireserve. The applied management aimed at two goals: 1. To reduce endotoxin production and acidosis in the horses by reducing the ingestion of carbohydrate rich food. 2. To reduce the mares level of activity and to prevent tearing of the suspensory apparatus of the coffin bone. To achieve these two goals it was decided to remove the three laminitic mares from the rich pasture in the main part of the semireserve and to confine them onto the poorer pasture of the small separately fenced area. All three affected mares had fully recovered from their laminitic condition. Prevention of grass laminitis can be achieved by the following measures: 1. Reduction in grass intake could be achieved by increasing the grazing pressure by an increase in stocking rate of the horses or mixed grazing with another species such as sheep. 2. A longer term solution to the problem may well be to sow specific varieties of grass with lower concentrations of water soluble carbohydrate.

Milkborne Campylobacter Infection in Hungary

In April 1998, an annual 2-day animal farm sale was held in Hódmezővásárhely, where 500 to 600 visitors consumed unpasteurized milk. The first signs of disease began 2 days after the end of the sale. Fifty-two people from a wide age range fell ill, primarily with inflammatory enteritis. These cases included 34 with Campylobacter positivity: 30 with Campylobacter jejuni and 4 with Campylobacter coli. Environmental samples (raw milk, udder swabs, and rectal swabs from 12 cows in the suspected herd) were tested 2 weeks after the first signs of the disease, and two rectal swabs were found to be positive for C. jejuni.. Initially, the epidemic seemed to be sporadic and, accordingly, only 26 human and 2 animal Campylobacter isolates were reserved for randomly amplified polymorphic DNA analysis. This comparative analysis verified that fecally contaminated milk was the source of the outbreak. The DNA-banding patterns of 20 C. jejuni isolates (19 human and 1 animal) were identical. The antibiotic susceptibilities of the Campylobacter isolates were determined, and only six C. jejuni (human) isolates, one C. coli (human) isolate, and one C. jejuni (animal) isolate were resistant to tetracycline, both by disk diffusion and by E test (antimicrobial gradient strip for the quantitative determination of susceptibility or resistance of microorganisms). No plasmid was detected in these tetracycline-resistant isolates. The endotoxin production of Campylobacter isolates was examined via the cytopathogenic effect on the Vero cell line. This effect exhibited various degrees of positivity in 19 cases. Only two human C. jejuni isolates displayed ++++ positivity. Both isolates were from patients who had required antibiotic therapy and hospital care.

Foam control in biopesticide production from sewage sludge

Several antifoam agents were evaluated for the ability to control foam in the production of Bacillus thuringiensis-based biopesticides using sewage sludge as a raw material. Experiments were conducted in shake flasks as well as in 15 l fermentors with controlled parameters. Polypropylene glycol (PPG), the most commonly used antifoam agent in B. thuringiensis fermentation, inhibited cell growth, sporulation and decreased the entomotoxicity yield even at a concentration of 0.1% (v/v) in sewage sludge medium. About 40% reduction in entomotoxicity was observed when PPG was used at 0.3% (v/v). The impact of PPG on sporulation and toxin synthesis in tryptic soy yeast broth (TSYB) medium was also studied. The inhibitory effects were less severe in TSYB than in sludge medium. Another silicone-based antifoam agent, “Antifoam A”, showed less severe effect on growth and stendotoxin production. The problem of the inhibitory effect of chemical antifoam agents on growth and endotoxin production was minimised substantially with the use of vegetable oils such as canola, olive, and peanut oils. Canola and peanut oil stimulated both sporulation and δ-endotoxin synthesis. The stimulus effect varies with the monounsaturated fat contents of oils. Journal of Industrial Microbiology & Biotechnology (2000) 25, 86–92.

Modulating effects of the feeding route on stress response and endotoxin translocation in severely stressed patients receiving thoracic esophagectomy

Experimental studies have demonstrated that the route of nutritional supply impacts the systemic metabolic responses after surgical injury. Intestinal mucosal atrophy, as induced by total parenteral nutrition (TPN) or prolonged bowel rest, has been reported to enhance bowel endotoxin translocation. The operative procedure for thoracic esophageal cancer, including thoracotomy, laparotomy, and three-field lymph-node dissection, is a particularly stressful surgery that requires long-term aggressive nutritional support and often results in the postoperative hypermetabolic state, leading to perturbation of postoperative immune function. Interleukin-6 (IL-6) plays an important role in host inflammatory responses, whereas IL-10 is linked to suppression of cellular immunity. The aim of this study was to investigate how the antecedent nutritional routes influence systemic IL-6 and IL-10 responses and endotoxin translocation after an operation for thoracic esophageal cancer. Twenty-nine patients who underwent esophagectomy with three-field lymphadenectomy were investigated. They were assigned to groups receiving either TPN ( n = 18) or enteral nutrition (EN; n = 11) providing 35 kcal · kg −1 · d −1 of energy and approximately 1.2–1.5 g · kg −1 · d −1 of amino acids. These nutritional supports were conducted from 1 wk before the operation to 14 d after the operation. Serum IL-6, IL-10, and endotoxin concentration were measured before and during the operation and at 2 h and 1, 3, and 7 d after the operation. IL-6 in sera was significantly higher after the operation in both groups. In the EN group, however, significantly less IL-6 production was observed on the third and seventh postoperative days when compared with those patients in the TPN group. Similarly, serum IL-10 concentration in the TPN group showed a significantly higher level than that in the EN group. Serum IL-6 showed a significant positive correlation with IL-10 at 2 h and at 7 d after the operation, suggesting that the reduced inflammatory responses were related to the inhibition of the development of postoperative immunosuppression. Endotoxin concentration in sera was significantly lower in the EN group after the operation than in the TPN group. Perioperative EN provides better regulation of inflammatory cytokine responses and may contribute less to immunosuppression after major surgery than parenteral nutrition. The attenuated production of endotoxin induced by EN may play an important role in these phenomena.

Suckling CD1 mice as an animal model for studies of Legionella pneumophila virulence.

On the assumption that specific host defences are lower in newborn and infant animals, the susceptibility of CD1 suckling mice to Legionella pneumophila was studied with the hypothesis that this model could detect consistent differences in virulence among Legionella isolates from various clinical and environmental sources. Mice 3-14 days old were indeed markedly susceptible to intraperitoneal challenge with fresh clinical isolates, but not to serially subcultured or type collection strains of L. pneumophila. For example, intraperitoneal inoculation of 10(7) cells of a fresh clinical isolate of L. pneumophila (strain Monza 3) caused 60% mortality of suckling mice in 1 day whereas the same number of cells of a culture-attenuated derivative (strain Monza 3p50) caused <10% mortality in >15 days. Lethal infection by the 'virulent' Monza 3 strain was strictly dependent on mouse age (no death was observed in mice >26 days old), required the inoculation of viable cells and was not related to endotoxin production. The 'virulent' L. pneumophila strain was cleared from mouse lungs less rapidly, while adhering to, and being internalised into the peritoneal exudate cells (PEC) of suckling mice to a greater extent, than the avirulent derivative, as shown by immunofluorescence and confocal microscopy. The Monza 3 strain also induced the production by PEC in vivo of 5-to-10 times more tumour necrosis factor-alpha (TNF-alpha) mRNA than the Monza 3p50 strain. Overall, suckling CD1 mice appear to provide a promising, easily handled, highly reproducible and relatively inexpensive animal model for studies of the virulence of L. pneumophila, and possibly, of the role of pro-inflammatory cytokine production in this phenomenon.

Effect of Kupffer cell phagocytosis blockade induced by gadolinium chloride and carrageenan on endotoxin sensitivity, tissue localization of endotoxin and TNF production

Several recent data suggest that in severe injuries, such as a shock state, the gradual activation of Kupffer cells and the excessive release of destructive and immunosuppressive products from macrophages may contribute to the development of “multiple organ failure”. The effect of Kupffer cell phagocytosis blockade on the correlation between the tissue distribution of bacterial lipopolysaccharide (LPS), endotoxin sensitivity and LPS-induced tumor necrosis factor (TNF) production was investigated in in vivo experiments in mice. To depress the activity of the Kupffer cells, gadolinium chloride (GdCl 3) or carrageenan was used. The studies indicated the dissociation of the tissue localization of 51Cr-labeled endotoxin and endotoxin lethalithy. Both GdCl 3 and carrageenan depressed the Kupffer cell activity, but the endotoxin sensitivity was enhanced only by carrageenan treatment. However, there was a close correlation between the sensitivity to LPS and LPS-induced TNF production as measured in the serum, since LPS-induced TNF production was enhanced only by carrageenan treatment.

赤血球Ｍ・Ａ・Ｐ中におけるＹｅｒｓｉｎｉａ ｅｎｔｅｒｏｃｏｌｉｔｉｃａの増殖とエンドキシン及び上清ヘモグロビンの産生について

Contamination of Yersinia enterocolitica (Y. e.) in preserved red cell concentrates with an additive solution (RC-MAP) has been gathering recent concern. It is useful to detect contamination of RC-MAP with Y. e. at an early stage of storage. Since Y. e. proliferates to produce endotoxin and free hemoglobin (Hb) in plasma, we examined the relation of proliferated amount of Y. e. to production of endotoxin and free Hb in RC-MAP stored at 4°C for 42 days, in comparison to that in RC-MAP without Y. e. as a control.Y. e. was inoculated to give a concentration of 115-130CFU/ml into whole blood (n=5) at two hours after collection. The proliferation of Y. e. in RC-MAP was recognized at 10 days after the inoculation and endotoxin was also found at the same time. However, the endotoxin could not be detected earlier than the proliferation of Y. e. The increase of free Hb in plasma was not recognized before Y. e. had proliferation above 107-108CFU/ml, while there was one sample with no increase of free Hb in plasma in spite of the presence of Y. e. at 108CFU/ml.The color changes of RC-MAP from outward appearance occurred 2-3 weeks after Y. e. had proliferated to 108CFU/ml.These findings indicate that the amount of endotoxin and free Hb in plasma do not predict the contamination of Y. e. in RC-MAP in advance, although testing for them just before transfusion may be helpful to prevent transfusion-related sepsis due to Y. e. Further studies are required to find other measures to detect Y. e. in contaminated RC-MAP.

Antibiotics prevent liver injury in rats following long-term exposure to ethanol

Background/Aims: Kupffer's cells participate in alcohol-induced liver injury, and endotoxemia is observed in human alcoholics and in a rat model. This study evaluated the effect of reducing bacterial endotoxin production by intestinal sterilization on alcohol-induced liver injury. Methods: Male Wistar rats were exposed to ethanol continuously for up to 3 weeks via intragastric feeding. The gut was sterilized with polymyxin B and neomycin. Results: Fecal culture of stool samples from ethanol-fed rats treated with antibiotics showed virtually no growth of gram-negative bacteria. Endotoxin levels of 80–90 pg/mL in plasma of ethanol-fed rats were reduced to <25 pg/mL by antibiotics. Antibiotic treatment also completely prevented elevated aspartate aminotransferase levels and significantly reduced the average hepatic pathological score in rats exposed to ethanol. Oxygen tension on the surface of the liver measured in vivo was decreased significantly from control values of 48 ± 1 to 39 ± 1 μmol/L in ethanol-treated rats. This hypoxia was prevented by treatment with antibiotics. Moreover, the increase in rates of ethanol elimination due to long-term ethanol treatment was prevented by antibiotic treatment. Conclusions: Intestinal sterilization prevented alcohol-induced liver injury in the rat, supporting the idea that hypermetabolism and consequent hypoxia caused by activation of Kupffer's cells by endotoxin is involved in the mechanism.

Effects of Accidental Trauma on Cytokine and Endotoxin Production

Objective.To determine the effects of accidental injury of varying severity on interleukin (IL)-lα, IL-6, IL-8, tumor necrosis factor-α (TNF-α), and endotoxin release.Design.Prospective, multi-unit, longitudinal study.Setting.Emergency Departments and intensive care units of two university hospitals

Effects of accidental trauma on cytokine and endotoxin production

To determine the effects of accidental injury of varying severity on interleukin (IL)-1 alpha, IL-6, IL-8, tumor necrosis factor-alpha (TNF-alpha), and endotoxin release. Prospective, multi-unit, longitudinal study. Emergency Departments and intensive care units of two university hospitals. Trauma patients after mild, moderate, and severe injury (Injury Severity Score of < or = 10, 11 to 24, and > or = 25, respectively). None. Plasma cytokine and endotoxin concentrations were measured over a 5-day period, starting within 2 hrs of accidental injury. An enzyme-linked immunosorbent assay was used to determine plasma concentrations of IL-1 alpha, IL-6, IL-8, and TNF-alpha. Plasma endotoxin concentrations were measured using a chromogenic limulus amebocyte assay. Preresuscitation samples obtained immediately on arrival in the Emergency Department, and within 2 hrs of injury, demonstrated significant increases of IL-6 and IL-8 concentrations in the severe injury group, in contrast to minimal increases seen after mild or moderate injury. Analysis of serial postresuscitation samples demonstrated rapid increases in IL-6 and IL-8 concentrations within 12 hrs of injury. IL-6 and IL-8 remained increased for 24 hrs after injury, then decreased markedly from their peak values during the next 24 hrs. Increased circulating concentrations of these cytokines continued to be present for > 5 days in the severely injured patients. IL-6 and IL-8 concentrations were only minimally increased in patients 8 and 24 hrs after moderate injury. Endotoxin and IL-1 alpha were not found in any samples, including those samples obtained serially from severely injured patients. No patient at any time point had TNF-alpha concentrations of > 35 pg/mL. These results demonstrate that severe injury produces rapid, large increases in circulating concentrations of IL-6 and IL-8 that may contribute to the frequent development of the adult respiratory distress syndrome and multiple organ system failure in this clinical setting.

Bacillus thuringiensis growth, sporulation and ?-endotoxin production in oxygen limited and non-limited cultures

The production of crystals and spores ofBacillus thuringiensis var.israelensis was studied under different aeration conditions. The results with 4 l batch cultures showed that for O2 non-limited, cultures cell yield, toxin production and spore count were constant for all oxygen transfer rates (OTR). Under O2 limitation, °-endotoxin concentrations and spore counts were lower than those obtained in non-limited cultures. In addition, δ-endotoxin yields diminished under O2 limitation, suggesting that the toxin synthesis mechanism could have been affected.

Sequential development of antigens and toxins of Pasteurella haemolytica serotype 1 grown in cell culture medium

Summary Pasteurella haemolytica was grown in nonsupplemented cell culture medium, or in medium supplemented with bovine serum albumin (bsa) for 24 hours. The production of leukotoxin (lkt) and endotoxin was sequentially evaluated, as were bacterial antigens associated with bacterial cell lysates and culture supernates. Supplementation of medium with bsa had no effect on bacterial growth curves; however, lkt activity was detected earlier and was greater in culture supernates from bsa-Supplemented media than from nonsupplemented medium. Leukotoxin antigen (105 kDa) was detected in culture supernates, using a monoclonal antibody, immunoblot analysis, and densitometry. The relative concentrations of lkt antigen were proportional to lkt activity. Endotoxin activity was initially lowest in the culture supernates from nonsupplemented medium, but increased during the incubation period, whereas endotoxin activity in bsa-supplemented culture supernates decreased with time in culture. In culture supernates from nonsupplemented medium, the number of antigenic bands identified by immunoblot analysis with hyperimmune anti-P haemolytica and densitometry was greater than in culture supernates from supplemented media. In bacterial lysates, a 95-kDa antigen was the major antigen detected, using the anti-lkt monoclonal antibody. The concentration of that antigen varied among lysates from nonsupplemented medium and bsa-supplemented media. Using hyperimmune anti-P haemolytica serum, minor differences were seen in the relative quantities of lysate-associated antigens dependent on time in culture and medium used. Among the major antigens seen, differences were most apparent for 150-, 100-, and 87-kDa antigens, whereas differences were not obvious for 42-40-, and 30-kDa antigens. In conclusion, at various times in culture, moderate differences were evident in P haemolytica antigens or toxins in bacterial lysates or culture supernates, and the presence of bsa in the medium altered antigenic profiles and toxin concentrations.

Pyrogenic reactions in patients receiving conventional, high-efficiency, or high-flux hemodialysis treatments with bicarbonate dialysate containing high concentrations of bacteria and endotoxin.

High-efficiency (HE) and high-flux (HF) hemodialysis are becoming increasingly popular methods for treating patients with chronic renal failure because they reduce the time required for dialysis treatment. HF and HE dialyzers require bicarbonate dialysate, often prepared from concentrates that can support bacterial growth with endotoxin production. There is a concern that endotoxins or bacteria may cross or interact at the membranes of these dialyzers, triggering the release of endogenous pyrogens (cytokines) by peripheral blood mononuclear cells to cause pyrogenic reactions (PR). To determine the incidence of PR and to examine the association between PR and levels of bacteria and endotoxin in dialysate, a cohort of patients receiving conventional, HE, or HF hemodialysis with bicarbonate dialysate and reprocessed dialyzers at three dialysis centers during a 12-month period was studied prospectively. All dialyzers underwent a test of membrane integrity before use. A total of 19 PR were identified among 18 patients in 26,877 hemodialysis treatments (0.7 PR/1,000 treatments). There was no significant difference in PR rates by treatment modality: conventional, 0.5 per 1,000 (7 PR/13,123 treatments) versus HE, 0.9 per 1,000 (9 PR/11,345) versus HF, 1.2 per 1,000 (3 PR/2,409) (P = 0.21; chi 2 test). Throughout the study period, bacterial counts for dialysate at each center significantly exceeded the Association for the Advancement of Medical Instrumentation's (AAMI) microbiologic standards for dialysate of less than 2,000 CFU/mL (mean, 19,000 CFU/mL), but water used in the reuse of dialyzers tested less than 200 CFU/mL.(ABSTRACT TRUNCATED AT 250 WORDS)

CHANGES IN THE FECAL MICROFLORA IN PATIENTS WITH CARCINOMA OF THE LARGE BOWEL

The changes in the intestinal microflora were examined in patients with advanced carcinoma of the large intestine, and healthy subjects were surved as control. Comparing to control, patients group revealed high fecal moisture and fecal pH, but showed low levels in various organic acids except succinic acid. Only succinic acid was detected in high level and frequency. No significant difference in the number and occupation rate of Gram-positive bacteria participating in the endogenous endotoxin production was noted between both groups. The pattern of fecal microflora in patients group was similar to that in control. However, the aerobic microorganisms including Staphylococcus were highly found in patients group. These results suggested that the colonic enviornment of the patients with large bowel carcinoma was in aerobic state in comparison with healthy subjects.