The association between fluid administration and outcome following major burn: a multicenter study

OBJECTIVE

To determine patient and injury variables that influence fluid requirements following burn injury and examine the association between fluid volume received and outcome.

BACKGROUND

Fluid resuscitation remains the cornerstone of acute burn management. Recent studies suggest that patients today are receiving more fluid per percent total body surface area (TBSA) than in the past. Therefore, there is a need to better define the factors that impact fluid requirements and to determine the effects of fluid volumes on outcome.

METHODS

This study was part of a federally funded multicenter study. Multilinear regression analyses were performed to determine the patient and injury characteristics that most influenced fluid resuscitation volumes received. To assess the association of fluid volumes on outcome, propensity scores were developed to provide a predicted volume of fluid for each patient. Logistic models were then used to assess the impact of excess fluid beyond predicted volumes on outcome.

RESULTS

Seventy-two patients were included in this analysis. Average patient age was 40.6 years and average TBSA was 44.5%. Average fluid volume received during the first 24 hours after injury was 5.2/mL/kg/TBSA. Significant predictors of fluid received included % TBSA, age, intubation status, and weight. Increased fluid volume received increased risk of development of pneumonia (odds ratio [OR] = 1.92), bloodstream infections (OR =2.33), adult respiratory distress syndrome (OR = 1.55), multiorgan failure (OR= 1.49), and death (OR = 1.74).

CONCLUSION

TBSA, age, weight, and intubation status on admission were significant predictors of fluid received. Patients who received larger volumes of resuscitation fluid were at higher risk for injury complications and death.

N-sulfonato-N,O-carboxymethylchitosan: A novel polymeric absorption enhancer for the oral delivery of macromolecules

Chitosan has been shown to act on the mucosal epithelial barriers mainly when protonated at acidic pH values in which it is soluble. Soluble chitosan is able to improve the permeation and absorption of neutral to cationic macromolecules only, as it forms polyelectrolyte complexes with anionic macromolecules. LMWH (Low Molecular Weight Heparin) is an anionic polysaccharide finding clinical application as an improved antithrombotic agent compared to Unfractionated Heparin (UFH). In this study we have employed N-sulfonato-N,O-carboxymethylchitosan (SNOCC) as a potential intestinal absorption enhancer of LMWH, Reviparin. SNOCC was prepared at 3 different viscosity grades 20, 40 and 60 cps and identified as SNOCC-20, SNOCC-40 and SNOCC-60, respectively. SNOCC materials were tested in vitro for their ability to decrease the Trans Epithelial Electrical Resistance (TEER) of Caco-2 cell monolayers. They were further tested as transport enhancers of hydrophilic compounds such as (14)C-mannitol, FITC-Dextran (MW 4400 Da) and Reviparin (LMWH). Solutions of Reviparin, with or without SNOCC, were administered intraduodenally in vivo in rats and the absorption of the drug was assessed by measuring the Anti-Xa levels in rat plasma. In vitro studies showed that SNOCC materials were able to induce a concentration dependent decrease in the TEER of the Caco-2 monolayers. SNOCC-40 and -60 were shown to decrease resistance more readily compared to the low viscosity SNOCC-20. (14)C-mannitol permeation data across intestinal epithelia were in agreement with the observed decrease in TEER; the higher viscosity SNOCC-60 was the most effective demonstrating a 51-fold enhancement of the permeation of the radiolabeled marker. Studies with both FITC-Dextran and Reviparin demonstrated significantly increased permeation across Caco-2 cell monolayers when they were co-incubated at the apical side of the monolayer. Intestinal absorption of Reviparin in rats was increased when it was co-administered with SNOCC-40 and -60, in agreement with in vitro data. Anti-Xa levels were elevated to and above the antithrombotic levels and were sustained for at least 6 h, giving an 18.5-fold increase in the AUC of LMWH in rats. In conclusion, SNOCC-40 and -60 have been shown to enhance both permeation and absorption of Reviparin across intestinal epithelia proving their potential as polymeric absorption enhancers.

Serum cartilage oligomeric matrix protein and other biomarker profiles in tibiofemoral and patellofemoral osteoarthritis of the knee

OBJECTIVES

There is some evidence that tibiofemoral osteoarthritis (TFJ OA) and patellofemoral osteoarthritis (PFJ OA) may have different risk factors. To investigate the possibility that these conditions are separate disease entities, we compared biomarker profiles of patients with each disease.

METHODS

Serum samples were taken from 222 patients who had knee pain and X-ray signs of knee OA. Eighty-two had only medial TFJ OA and 38 only PFJ OA in one or both knees. The remaining patients had either mixed disease or equivocal radiographic evidence of OA. The following biomarkers were measured in serum samples from baseline and follow-up visits: cartilage oligomeric matrix protein (COMP), glycosaminoglycan, keratan sulphate epitope 5D4, YKL-40, osteocalcin, C-telopeptide of type I collagen, hyaluronan and C-reactive protein.

RESULTS

The two subsets of OA (TFJ and PFJ) had similar radiographic disease severity and there were no significant differences in the presence and patterns of pain scores (visual analogue scale and Western Ontario and McMaster Universities Osteoarthritis Index). No difference was found for the biomarkers between the two groups, with one exception. Both baseline and area under the curve per month COMP concentrations were significantly higher in the TFJ than the PFJ group (P<0.01).

CONCLUSIONS

The reduced serum COMP in PFJ disease compared with TFJ OA could be due to small articular cartilage volume in the latter or to a qualitative difference in cartilage metabolism.

Identification of novel single nucleotide polymorphisms in intron 1B and exon 1C of the human interleukin-1 receptor type I (IL-1RI) gene

We have identified two novel single nucleotide polymorphisms in the 5' region of the human IL-1RI gene: (1) A-->G at position 52 in intron 1B (GenBank accession number AF146426), which creates an Mspl restriction endonuclease site. Allele frequencies in a Caucasian population were 0.1 (A allele) and 0.9 (G allele). (2) A-->T at position 140 in exon 1C (GenBank accession number AF146427). Allele frequencies in a Caucasian population were 0.27 (A allele) and 0.73 (T allele).

Acyl CoA and lipid synthesis from ketone bodies by the extramitochondrial fraction of hepatoma tissue

The compartmentation of the pathway for the synthesis of lipids from ketone bodies was examined in a cell free, post-mitochondrial supernatant fraction of malignant Morris hepatoma 7777 tissue. A fortified supernatant system effectively incorporated radioactive D(-)-3-hydroxybutyrate and acetoacetate into cholesterol and fatty acids, and both ketone bodies were directly converted to their CoA thioesters. Furthermore, a microsome-free (100,000 x g) cytosolic fraction was also able to acylate 3-hydroxybutyrate to 3-hydroxybutyryl CoA. No previous identification of this enzyme activity has been described. These results which characterize a distinct extramitochondrial pathway for conversion of 3-hydroxybutyrate as well as acetoacetate into lipids also suggest the possibility of a previously undetected enzymatic activity for utilization of this ketone body.

Utilization and preferred metabolic pathway of ketone bodies for lipid synthesis by isolated rat hepatoma cells

Morris hepatoma 7777 cells freshly isolated from highly malignant tumors grown in the hindlimb of buffalo rats actively convert ketone bodies to cholesterol and fatty acids. On the basis of results obtained with (-)-hydroxycitrate, an inhibitor of the ATP citrate lyase enzyme, the metabolic pathway for acetoacetate conversion to lipids is exclusively cytoplasmic, whereas that for 3-hydroxybutyrate involves both extra- and intramitochondrial compartments. Subcellular distribution studies indicated accumulation and compartmentation of 3-hydroxybutyryl CoA primarily in the cytoplasm of hepatoma cells incubated with either ketone body. In contrast, the compartmentation of acetoacetyl CoA is dependent on whether the substrate is acetoacetate or 3-hydroxybutyrate. With acetoacetate, the acetoacetyl CoA is entirely cytoplasmic, whereas with 3-hydroxybutyrate, it is equally divided between the intra- and extramitochondrial compartments. The results are discussed in terms of the known and proposed metabolic pathways for lipid synthesis from ketone bodies, particularly that from 3-hydroxybutyrate.

Interleukin 1 alpha and beta production by cells isolated from membranes around aseptically loose total joint replacements

Aseptic loosening of joint prostheses is accompanied by local osteolysis. To determine whether local production of interleukin 1 might contribute to such lysis, the number of interleukin 1 secreting cells in the pseudosynovial membrane surrounding prostheses was measured. Interleukin 1 alpha and beta secreting cells were identified by ELISPOT, a sensitive cytokine secreting assay. The proportion of interleukin 1 beta secreting cells in pseudosynovial membrane was comparable with the proportion occurring in the synovium of patients with rheumatoid arthritis and higher than that in normal subjects and patients with osteoarthritis. The proportion of interleukin 1 alpha producing cells was higher in pseudosynovial membrane than in diseased synovium. Overall, higher numbers of interleukin 1 beta than interleukin 1 alpha secreting cells were detected. A correlation was observed between the number of cells in pseudosynovial membrane producing interleukin 1 beta and those producing interleukin 1 alpha. When divided into area of origin, tissue samples from the femoral area contained a higher proportion of interleukin 1 beta producing cells than tissue in the acetabular or capsular regions, though due to variance within each group this difference did not reach significance.

The role of oil and agalactosyl IgG in the induction of arthritis in rodent models

The proportion of agalactosyl IgG [Gal(O)] is raised in human rheumatoid arthritis and tuberculosis. We report here that injection of pristane into the peritoneal cavities of mice on days 0 and 50, which is known to induce plasmacytomas and arthritis, also induced a rise in the proportion of Gal(O), correlating with a simultaneous rise in the level of IgG antibody binding to the 65-kDa heat-shock protein of Mycobacterium bovis (hsp65). Arthritis developed in a proportion of those CBA/Igb mice with the highest percentage of Gal(O). Pretreatment with 50 micrograms of recombinant mycobacterial hsp65 intraperitoneal (i.p.) on day -10, or with 500 rad irradiation on day -2 before the first of the two injections of pristane reduced the incidence of arthritis from 24% in control animals, to 5.3% and 0.4%, respectively. The reduced incidence of disease correlated with smaller rises in the % Gal(O) at 50-75 days, although levels at 150-200 days were not affected. The arthritogenic effect of oil was not confined to the pristane model, since a single i.p. injection of oil 21 days before immunizing DBA/1 mice with type II collagen reduced the mean day of onset of this arthritis, [which we have previously shown to correlate with raised % Gal(O)], from 38 to 15 days (p less than 0.001). One interpretation is that an autoimmunogenic stimulus, given when % Gal(O) is raised, is more likely to evoke disease. Since oil granulomata are known to secrete interleukin 6, which has B cell-regulatory properties and is secreted by rheumatoid synovial cells, we tested sera from interleukin 6-transgenic mice, and found a strikingly raised percentage of Gal(O). We suggest, therefore, that the role of oil in the induction of arthritis is the dysregulation of cytokine release of which a raised percentage of Gal(O) may be a direct or indirect consequence, associated with an increased susceptibility to autoimmunogenic stimuli.

Severe combined immunodeficient (SCID) mice: a model for investigating human thyroid autoantibody synthesis

We have studied the ability of lymphocytes from the blood, thyroid and lymph nodes of patients with autoimmune thyroid disease (AITD) to produce autoantibodies to thyroglobulin (Tg) and/or thyroid peroxidase (TPO) in SCID mice. Human IgG class Tg and/or TPO antibodies were detectable in plasma from SCID mice 7 days after transfer of 15-25 x 10(6) cells/mouse and the highest levels were recorded 2-3 weeks later. In contrast, Tg and/or TPO antibodies were undetectable in recipients of lymphocytes from thyroid antibody negative controls. AITD thyroid lymphocytes produced the most antibody in recipient mice and lower levels were observed in recipients of AITD blood and lymph node lymphocytes. The amounts of Tg and/or TPO antibody detected were in accordance with the ability of thyroid and lymph node lymphocytes to secrete these autoantibodies spontaneously in culture (indicating the presence of cells activated in the patient) and with the capacity of blood lymphocytes (probably B memory cells) to secrete Tg and/or TPO antibodies in culture in response to pokeweed mitogen. Tg antibodies in plasma from SCID recipients of thyroid lymphocytes were of subclasses IgG1, IgG2 and IgG4 and the proportions closely resembled those of the donor's serum Tg antibodies. Blood lymphocytes transferred to SCID recipients were also able to produce Tg antibodies of subclasses 1, 2 and 4 but the subclass distribution varied between mice and the reason for this is not clear at present. Since SCID mice provide an environment in which B lymphocytes from patients with AITD can be activated without mitogen to secrete thyroid antibodies, this model will provide a powerful system for elucidating the mechanisms regulating the secretion of human antibodies to Tg and TPO.

Antibody producing capacity to the bacteriophage phi X174 in rheumatoid arthritis

A study of antibody production in response to a primary immunogen, the bacteriophage phi X174, was performed in 27 patients with rheumatoid arthritis and 15 controls. All patients produced a primary (IgM) response to initial immunisation. The frequency distribution of peak antibody titres after secondary immunisation showed a marked difference between the patients and controls, with 10 patients having peak titres below 5000. The IgG component of the antibody response expressed as a percentage of total phage antibody on the 10th day after secondary immunisation was less in the patients than in the control group. There was no correlation between antibody titres and indices of disease activity, rheumatoid factor titres, or the presence of DRw4, DRw3, and DRw2. After secondary immunisation the patients with rheumatoid arthritis were treated with D-penicillamine, azathioprine, levamisole, or maintained on a non-steroidal anti-inflammatory drug. Assessment of response to tertiary immunisation again showed an impairment of antibody production in the rheumatoid group receiving non-steroidal anti-inflammatory drugs compared with the controls. None of the drugs, D-penicillamine, azathioprine, or levamisole, produced further suppression or augmentation of antibody production in response to the immunogen.

Suppression of cholesterogenesis by plant constituents: review of Wisconsin contributions to NC-167

In animals, non-sterol metabolites of the mevalonate pathway act independently from receptor-mediated cholesterol uptake in the multivalent feedback regulation of mevalonate biosynthesis. Studies leading to the isolation and characterization of plant-borne suppressors of mevalonate biosynthesis are reviewed. We propose that one cardio-protective component of the vegetarian diet consists of a variety of non-sterol, post-mevalonate metabolites. These products of plant branches of the mevalonate pathway, discarded as animals evolved, continue to influence animal sterol metabolism. It is through this action, we propose, that the cholesterol-suppressive action of plant materials is expressed.

Glyceroneogenesis in rat and guinea pig adipose tissue during the fed and fasted states

While both pyruvate and lactate are good substrates for glyceride-glycerol synthesis in isolated adipocytes from fed rats and guinea pigs, neither alanine nor serine appear to support glyceroneogenesis. Fasting increases the proportion of radioactive pyruvate or lactate incorporated into glyceride-glycerol and reciprocally decreases the proportion incorporated into fatty acids. However, the total incorporation of radioactivity into triacylglycerol is considerably lower in isolated adipocytes from fasted than from fed animals. Addition of glucose to the incubation medium promotes the incorporation of radioactive lactate into both fatty acids and glyceride-glycerol by adipocytes from fasted as well as fed animals. The concentration of alpha-glycerolphosphate is considerably higher in adipose tissue of fed than fasted animals. In general, these results support the presence of a glyceroneogenic pathway in rat and guinea pig adipose tissue. However, it would appear that the physiologic significance of this pathway is less important in the fasted than the fed state, where it may play some role in the esterification of intracellular fatty acids.

Purification and properties of a cytosol Ca2+-activated ATPase from Tetrahymena pyriformis

A Ca2+-activated ATPase has been isolated from the cytosol of Tetrahymena pyriformis. The enzyme, whose specific activity increases with culture age, was purified to homogeneity from extracts of stationary phase cells. The pure enzyme which has a molecular weight of 89,000 was found to contain three identical subunits of molecular weight approximately 29,000. ATP is the preferred substrate for the enzyme and maximal activity is dependent on either Ca2+ or Ba2+. Inhibitors of known ATPases do not affect the enzyme activity. Antibodies developed against the pure enzyme only react with ATPase in the cytosol fraction prepared by differential centrifugation of a crude homogenate of cells. The function of the cytosol ATPase which has, thus far, only been detected in various strains of Tetrahymena pyriformis is presently under investigation.

Growth-dependent factors in the regulation of aminoacyl-tRNA synthetase activities of Tetrahymena pyriformis

Changes in phenylalanyl-tRNA synthetase (L-phenylalanine : tRNAPhe ligase, EC 6.1.1.20) and leucyl-tRNA synthetase (L-leucine : tRNALeu ligase. EC 6.1.1.4) activities were studied during the growth cycle of Tetrahymena pyriformis. High levels of charged tRNA observed during exponential growth were associated with elevated aminoacyl-tRNA synthetase activities. Low levels of charges tRNA in the stationary phase culture were associated with decreased aminoacyl-tRNA synthethase activities together with a concomitant accumulation of factor(s) which inhibited the enzyme activities. The inhibitory factor(s) has been partially purified and evidence is presented to rule out RNA, RNAases, proteases and ATPases as the responsible inhibitory factor(s) of the aminoacyl-tRNA synthetases.

Reversal of growth arrest in adolescents with Crohn's disease after parenteral alimentation

Growth arrest and delayed onset of puberty often complicate childhood onset Crohn's disease of the small bowel (granulomatous enteritis). Nutritional deficits arising from inadequate dietary intake, malabsorption, and increased caloric needs may contribute to growth retardation. To assess whether a sustained high caloric and nitrogen intake could reestablish growth, 4 children with extensive Crohn's disease of the small bowel were studied before and after parenteral alimentation which was instituted for symtomatic disease control. Weight gain, positive nitrogen balance, and improved nutritional status were achieved during parenteral alimentation in each patient. In 2 patients weight gain was sustained using oral nutritional supplements, and a substantial increase in linear skeletal growth continued in the ensuing months. One patient entered puberty within 4 months of parenteral alimentation and another had the onset of menarche and the development of secondary sex characteristics 4 months after parenteral alimentation and resection of diseased bowel. Growth may be reestablished in some growth-arrested children if intake is sufficient to establish a sustained positive caloric and nitrogen balance. Nutritional requirements imposed by the demands of growth and active disease and often compounded by the catabolic effects of corticosteroids may be excessive; growth may occur only if these needs are met orally and/or parenterally.

Relationship of adenosine 3',5'-monophosphate to growth and metabolism of Tetrahymena pyriformis

The concentration of adenosine 3',5'-monophosphate (cyclic AMP) and the activity of adenylate cyclase were determined for the first time in conjuncation with cyclic 3',5'-nucleotide phosphodiesterase (phosphodiesterase) during the growth cycle of Tetrahymena pyriformis. High levels of cyclic AMP observed during early exponential and late stationary phases were associated with elevated adenylate cyclase and decreased phosphodiesterase activities. Adenylate cyclase and cyclic AMP were decreased and phosphodiesterase was increased in cells grown in glucose-supplemented medium. In contrast to findings in mammalian liver, cyclic AMP was decreased during active gluconeogenesis in Tetrahymena. This suggests a different modulation of carbohydrate metabolism in the two species. The results illustrate that both the content of cyclic AMP and its action as a regulatory agent in Tetrahymena are uniquely suited to the metabolism of this organism.

Antimycin A: stimulation of cell division and protein synthesis in Tetrahymena pyriformis

Addition of antimycin A to a culture of Tetrahymena pyriformis caused an increase in cell division and protein synthesis in this ciliated protozoan. The antimycin effect is a function of the time of exposure to the antibiotic as well as of the age of the culture. A large accumulation of endoplasmic reticulum, reflecting increased protein synthesis, was visualized by electron microscopy in cells stimulated by the antimycin A.