OBJECTIVE

The aim of our study was to examine serum markers of the TNF and Fas pathways for association with cystatin-C based estimated glomerular filtration rate (cC-GFR) in subjects with type 1 diabetes (T1DM) and no proteinuria.

METHODS

The study group (the 2nd Joslin Kidney Study) comprised patients with T1DM and normoalbuminuria (NA) (n = 363) or microalbuminuria (MA) (n = 304). Impaired renal function (cC-GFR <90 ml/min) was present in only 10% of patients with NA and 36% of those with MA. We measured markers of the tumor necrosis factor alpha (TNFalpha) pathway [TNFalpha, soluble TNF receptor 1 (sTNFR1), and 2 (sTNFR2)], its downstream effectors [soluble intercellular and soluble vascular adhesion molecules (sICAM-1 and sVCAM-1), interleukin 8 (IL8/CXCL8), monocytes chemoattractant protein-1 (MCP1), and IFNgamma inducible protein-10 (IP10/CXCL10)], the Fas pathway [soluble Fas (sFas) and Fas ligand (sFasL)], CRP, and IL6.

RESULTS

Of these, TNFalpha, sTNFRs, sFas, sICAM-1, and sIP10 were associated with cC-GFR. However, only the TNF receptors and sFas were associated with cC-GFR in multivariate analysis. Variation in the concentration of the TNF receptors had a much stronger impact on GFR than clinical covariates such as age and albumin excretion.

CONCLUSIONS

Elevated concentrations of serum markers of the TNFalpha and Fas-pathways are strongly associated with decreased renal function in nonproteinuric type 1 diabetic patients. These effects are independent of those of urinary albumin excretion. Follow-up studies are needed to characterize the role of these markers in early progressive renal function decline.

Occurrence of amyloid beta (Abeta) dense-core plaques in the brain is one of the chief hallmarks of Alzheimer's disease (AD). It is not yet clear what factors are responsible for the aggregation of Abeta in the formation of these plaques. Using Tg2576 and PSAPP mouse models that exhibit age-related development of amyloid plaques similar to that observed in AD, we showed that approximately 95% of dense plaques in Tg2576 and approximately 85% in PSAPP mice are centered on vessel walls or in the immediate perivascular regions. Stereoscopy and simulation studies focusing on smaller plaques suggested that vascular associations for both Tg2576 and PSAPP mice were dramatically higher than those encountered by chance alone. We further identified ultrastructural microvascular abnormalities occurring in association with dense plaques. Although occurrence of gross cerebral hemorrhage was infrequent, we identified considerable infiltration of the serum proteins immunoglobulin and albumin in association with dense plaques. Together with earlier evidence of vascular clearance of Abeta, our data suggest that perturbed vascular transport and/or perivascular enrichment of Abeta leads to the formation of vasocentric dense plaques in Tg2576 and PSAPP mouse models of AD.

We have used ultrathin cryosectioning and immunogold cytochemistry to study the position of alpha-granules in the endocytic and biosynthetic pathways in megakaryocytes and platelets. Morphologically, we distinguished three types of granules; so-called multivesicular bodies type I (MVB I) with internal vesicles only, granules with internal vesicles and an electron dense matrix (MVB II), and the alpha-granules with mainly a dense content and often internal membrane vesicles at their periphery. The MVBs were prominent in cultured megakaryocytes and the megakaryoblastic cell line CHRF-288, but were less numerous in bone marrow megakaryocytes and platelets, whereas alpha-granules were most prominent in mature bone marrow megakaryocytes and in platelets. The internalization kinetics of bovine serum albumin-gold particles and of fibrinogen positioned the MVB subtypes and alpha-granules sequentially in the endocytic pathway. MVBs contained the secretory proteins von Willebrand factor (vWF) and beta-thromboglobulin (beta-TG), the platelet-specific membrane protein P-selectin, and the lysosomal membrane protein CD63. Within the MVBs, endocytosed fibrinogen and endogenous beta-TG were restricted to the matrix, while vWF was predominantly associated with internal vesicles. CD63 was also observed in association with internal membrane vesicles in the alpha-granules. These observations, and the gradual morphologic transition from granules containing vesicles to granules containing predominantly dense material, suggest that MVBs represent a developmental stage in alpha-granule maturation.

The preferential interactions of bovine serum albumin, lysozyme, chymotrypsinogen, ribonuclease A, and beta-lactoglobulin with polyethylene glycols (PEGs) of molecular weight 200-6,000 have been measured by dialysis equilibrium coupled with high precision densimetry. All the proteins were found to be preferentially hydrated in all the PEGs, and the magnitude of the preferential hydration increased with increasing PEG size for each protein. The change in the chemical potentials of the proteins with the addition of the PEGs had highly positive values, indicating a strong thermodynamic destabilization of the system by the PEGs. A viscosity study of the PEGs showed them to be randomly coiled polymers, as their radii of gyration were related to the molecular weight by Rg = aM0.55. The thickness of the effective shell impenetrable to PEG around protein molecules, calculated from the preferential hydration, was found to vary with PEG molecular weight in similar fashion as the PEG radius of gyration, supporting the proposal (Arakawa, T. & Timasheff, S.N., 1985a, Biochemistry 24, 6756-6762) that the preferential exclusion of PEGs from proteins is due principally to the steric exclusion of PEG from the protein domain, although favorable interactions with protein surface residues, in particular nonpolar ones, may compete with the exclusion. These thermodynamically unfavorable preferential exclusion interactions lead to the action of PEGs as precipitants, although they may destabilize protein structure at higher temperatures.

Idiopathic pulmonary arterial hypertension (PAH) is a rare disease with a poor prognosis. New therapies have improved the outcome of this condition; accordingly, the factors that determine outcome may have changed. We aimed to identify determinants of survival in a cohort of consecutive patients with PAH: which was idiopathic, familial, or associated with anorexigen use. We performed a retrospective cohort study of 84 consecutive patients with PAH who underwent initial evaluation at our center from January 1994 to June 2002. The primary outcome was death or lung transplantation. Survival at 1, 3, and 5 [corrected] years was 87%, 75%, and 61%, respectively. Multivariate analysis showed that being of African-American or Asian descent was associated with an increased risk of death. Warfarin use was associated with a reduced risk of death. Higher serum albumin and cardiac index and acute vasoreactivity were independently associated with improved survival. These data suggest that the determinants of outcome have changed. Race is identified as a new risk factor, which may be attributable to biologic or socioeconomic differences. Cardiac function and acute reactivity of the pulmonary vascular bed remain strong independent predictors of outcome.

This study evaluated the efficacy and safety of rosiglitazone monotherapy in patients with type 2 diabetes. After a 4-week placebo run-in period, 493 patients with type 2 diabetes were randomized to receive rosiglitazone [2 or 4 mg twice daily (bd)] or placebo for 26 weeks. The primary end point was change in hemoglobin A(1c); other variables assessed included fasting plasma glucose, fructosamine, endogenous insulin secretion, urinary albumin excretion, serum lipids, and adverse events. Rosiglitazone (2 and 4 mg bd) decreased mean hemoglobin A(1c) relative to placebo by 1.2 and 1.5 percentage points, respectively, and reduced fasting plasma glucose concentrations relative to placebo by 3.22 and 4.22 mmol/L, respectively. Fasting plasma insulin and insulin precursor molecules decreased significantly. Homeostasis model assessment estimates indicate that rosiglitazone (2 and 4 mg bd) reduced insulin resistance by 16.0% and 24.6%, respectively, and improved ss-cell function over baseline by 49.5% and 60.0%, respectively. Urinary albumin excretion decreased significantly in the rosiglitazone (4 mg bd) group. There was no increase in adverse events with rosiglitazone. In the short-term, rosiglitazone is an insulin sensitizer that is effective and safe as monotherapy in patients with type 2 diabetes who are inadequately controlled by lifestyle interventions.

OBJECTIVE

Anemia is prevalent in old age and is potentially modifiable, but its effects on physical function have not been determined. We examined whether anemia in older persons increases the risk of subsequent decline in physical function, as measured by objective performance-based tests.

METHODS

Participants in this 4-year prospective cohort study included 1146 participants, aged 71 years or older, living in Iowa and Washington counties, Iowa. Anemia was defined according to World Health Organization (WHO) criteria as a hemoglobin concentration below 12 g/dL in women and below 13 g/dL in men. An assessment of standing balance, a timed 2.4-m walk, and a timed test of five chair rises were used to assess physical performance; these were combined into a 0 (poor) to 12 (excellent) summary scale.

RESULTS

After adjustment for baseline performance score, health status, and demographic characteristics, anemia was associated with greater mean decline in physical performance over 4 years; the adjusted mean decline was 2.3 (95% confidence interval [CI]: 1.7 to 2.8) in subjects with anemia and 1.4 (95% CI: 1.2 to 1.5) in those without anemia (P = 0.003). The association between anemia and greater physical decline was also present in participants who were free of diseases associated with anemia (cancer, infectious disease, and renal failure), and after adjustment for serum cholesterol, iron, and albumin levels. Persons with borderline anemia, a hemoglobin concentration within 1 g/dL above the WHO criteria, also showed greater mean physical decline (1.8; 95% CI: 1.5 to 2.2) than did those with higher hemoglobin concentrations (P = 0.02).

CONCLUSIONS

This study suggests that anemia in old age is an independent risk factor for decline in physical performance.

The dynamics of protein molecules in the subnanosecond and nanosecond time range were investigated by time-resolved fluorescence polarization spectroscopy. Synchrotron radiation from a storage ring was used as a pulsed light source to excite the single tryptophan residue in a series of proteins. The full width at half maximum of the detected light pulse was 0.65 nsec, making it feasible to measure emission anisotropy kinetics in the subnanosecond time range and thereby to resolve internal rotational motions. The proteins investigated exhibit different degrees of rotational freedom of their tryptophan residue, ranging from almost no mobility to nearly complete freedom in the subnanosecond time range. The tryptophan residue of Staphylococcus aureus nuclease B (20,000 daltons) has a single rotational correlation time (varphi) of 9.9 nsec at 20 degrees C, corresponding to a rotation of the whole protein molecule. By contrast, bovine basic A1 myelin protein (18,000 daltons) exhibits varphi of 0.09 and 1.26 nsec, showing that the tryptophan residue in this protein is highly flexible. The single tryptophan of human serum albumin (69,000 daltons) has almost no rotational freedom at 8 degrees C (varphi = 31.4 nsec), whereas at 43 degrees C it rotates rapidly (varphi(1) = 0.14 nsec) within a cone of semiangle 26 degrees in addition to rotating together with the whole protein (varphi(2) = 14 nsec). Of particular interest in the large angular range (semiangle, 34 degrees ) and fast rate (varphi(1) = 0.51 nsec) of the rotational motion of the tryptophan residue in Pseudomonas aeruginosa azurin (14,000 daltons). This residue is known to be located in the hydrophobic interior of the protein. The observed amplitudes and rates of these internal motions of tryptophan residues suggest that elementary steps in functionally significant conformational changes may take place in the subnanosecond time range.

Vascular endothelial growth factor (VEGF) has been identified as a possible mediator of retinal neovascularisation (NV), but it is not certain if VEGF alone is sufficient to cause retinal NV. We sought to investigate this issue by implanting ethylene-vinyl acetate copolymer pellets that slowly release VEGF into the vitreous cavity of rabbits and primates. Eyes were examined by indirect ophthalmoscopy, fundus photography, and fluorescein angiography and then animals were killed at various time points and immunocytochemical and ultrastructural evaluations were carried out. Seven days after implantation of a pellet containing 30 micrograms of human recombinant VEGF into the vitreous cavity of rabbits, retinal blood vessels became dilated and tortuous, and between days 14 and 21, retinal NV was noted in all eyes. Fluorescein angiography showed profuse leakage of dye from the anomalous vessels. Immunohistochemical staining for proliferating cell nuclear antigen (PCNA) showed positively staining nuclei in many of the endothelial cells of new blood vessels on the surface of the retina. Six eyes implanted with control pellets containing vehicle and two eyes implanted with pellets containing 30 micrograms of human serum albumin alone showed no retinal vascular abnormalities. Implantation of pellets containing 100 micrograms of VEGF into the vitreous cavity of primates resulted in iris NV and retinal vascular dilation and tortuosity very much like that seen in humans with ischemic retinopathies. Immunohistochemical staining for serum albumin showed widespread severe breakdown of the blood-retinal barrier (BRB). Histology showed dilated thin-walled retinal vessels, but unequivocal retinal NV could not be identified and staining for PCNA was negative. These findings indicate that sustained intravitreal release of VEGF causes widespread retinal vascular dilation and breakdown of the BRB. Retinal NV seems to require persistent high levels of VEGF at the retinal surface and can be achieved in rabbits providing a potentially useful model of retinal NV, but is difficult to achieve in primates. The extensive VEGF-induced disruption of the blood-retinal barrier suggests that VEGF antagonists may provide a new therapy for patients with ischemic retinopathies and macular edema.

Cells of the neural crest participate in a major class of cell migratory events during embryonic development. From indirect evidence, it has been suggested that fibronectin (FN) might be involved in these events. We have directly tested the role of FN in neural crest cell adhesion and migration using several in vitro model systems. Avian trunk neural crest cells adhered readily to purified plasma FN substrates and to extracellular matrices containing cellular FN. Their adhesion was inhibited by antibodies to a cell-binding fragment of FN. In contrast, these cells did not adhere to glass, type I collagen, or to bovine serum albumin in the absence of FN. Neural crest cell adhesion to laminin (LN) was significantly less than to FN; however, culturing of crest cells under conditions producing an epithelioid phenotype resulted in cells that could bind equally as well to LN as to FN. The migration of neural crest cells appeared to depend on both the substrate and the extent of cell interactions. Cells migrated substantially more rapidly on FN than on LN or type I collagen substrates; if provided a choice between stripes of FN and glass or LN, cells migrated preferentially on the FN. Migration was inhibited by antibodies against the cell-binding region of FN, and the inhibition could be reversed by a subsequent addition of exogenous FN. However, the migration on FN was random and displayed little persistence of direction unless cells were at high densities that permitted frequent contacts. The in vitro rate of migration of cells on FN-containing matrices was 50 microns/h, similar to their migration rates along the narrow regions of FN-containing extracellular matrix in migratory pathways in vivo. These results indicate that FN is important for neural crest cell adhesion and migration and that the high cell densities of neural crest cells in the transient, narrow migratory pathways found in the embryo are necessary for effective directional migration.

OBJECTIVE

To determine the prevalence of vitamin D deficiency in pregnant women and their neonates and to examine factors associated with vitamin D deficiency.

METHODS

Population-based study of pregnant women and their neonates from South-eastern Sydney, Australia.

METHODS

Serum 25 hydroxy-vitamin D (25-OHD), PTH, calcium, albumin, phosphate and alkaline phosphatase were measured in women at 23-32 weeks gestation and on cord blood at delivery. Maternal skin phototype was recorded using the Fitzpatrick scale.

RESULTS

Vitamin D deficiency (defined as 25-OHD <or= 25 nmol/l) was found in 144 of 971 (15%) women and 98 of 901 (11%) neonates. Median 25-OHD was 52 nmol/l (range 17-174) in mothers and 60 nmol/l (17-245) in neonates. Maternal 25-OHD levels varied by season, with lowest levels in late winter/early spring (P < 0.001). Factors associated with maternal vitamin D deficiency in multiple logistic regression were (OR, 95% CI): maternal birthplace outside Australia: 2.2 (1.4-3.5, P = 0.001), dark skin phototype: 2.7 (1.6-4.5, P < 0.001), wearing a veil: 21.7 (11.7-40.3, P < 0.001) and younger maternal age: 0.93 (0.89-0.97, P = 0.001). Maternal vitamin D deficiency increased the risk of neonatal vitamin D deficiency (OR 17.2, 95% CI 8.8-34.3) and birth weight was lower among infants of deficient vs. sufficient mothers: mean (SD) 3245 g (545) vs. 3453 g (555), P < 0.001.

CONCLUSIONS

Vitamin D deficiency is common among pregnant women; immigrant, veiled and dark skinned women are at greatest risk. Maternal vitamin D deficiency increases the risk of neonatal vitamin D deficiency and lower birth weight.

To study the substrate specificity and mechanism of thioltransferase (TTase) catalysis, we have used 14C- and 35S-radiolabeled mixed disulfides of cysteine and glutathione (GSH) with various cysteine-containing proteins. These protein mixed disulfide substrates were incubated with glutathione, glutathione disulfide (GSSG) reductase, and NADPH in the presence or absence of thioltransferase. Glutathione-dependent reduction of protein mixed disulfides was monitored both by release of trichloroacetic acid soluble radiolabel and by formation of GSSG in an NADPH-linked spectrophotometric assay. GSH-dependent dethiolation of [35S]glutathione-papain mixed disulfide (papain-SSG) and the corresponding bovine serum albumin mixed disulfide (BSA-SSG) were catalyzed by thioltransferase (from human red blood cells) as shown by the radiolabel assay, and equivalent rates were measured by the spectrophotometric assay. Dethiolation of [35S]hemoglobin-glutathione mixed disulfide (Hb-SSG) was also catalyzed by TTase. In contrast, TTase did not catalyze GSH-dependent dethiolation of [14C]papain-SScysteine or [14C]BSA-SScysteine as measured by the radiolabel assay. [14C]Hb-SScysteine and Hb-SScysteamine also did not serve as substrates. In separate experiments, TTase from rat liver displayed analogous selectivity. Thus, thioltransferase (glutaredoxin) appears to be specific for glutathione-containing mixed disulfides. Apparent TTase catalysis of GSSG formation from the papain- and BSA-SScysteine mixed disulfides was observed by the spectrophotometric assay, but a lag phase occurred consistent with preenzymatic formation of GSScysteine which could serve as the actual TTase substrate. Two-substrate kinetic studies of TTase with GSH and GSScysteine gave patterns of parallel lines on double-reciprocal plots (1/V vs 1/[S]), consistent with a simple ping-pong mechanism involving a TTase-SSG intermediate.

The monoclonal antibody Ki67 recognizes an antigen expressed in all phases of the cell cycle except Go. It has been used in 141 biopsies from 138 patients with non-Hodgkin's lymphoma to identify proliferating cells in histological sections. A Ki67 index (the number of Ki67 positive tumour cells divided by the sum of Ki67 positive and negative tumour cells) has been derived by counting 1000 cells in each case. A correction for the presence of non-tumour cells has been incorporated by counting non-tumour cells in serial sections stained with a panel of other antibodies. A very strong correlation between a low Ki67 index (less than 20 per cent) and low grade histology and a high Ki67 index (greater than 20 per cent) and high grade histology was found (Chi2 = 98.0). Ninety-one patients could be analysed for survival and those with low grade lymphoma (n = 38) who had a relatively high Ki67 index (greater than 5 per cent) had a worse survival than those with an index of less than 5 per cent (p less than 0.05). In contrast, there was a trend for those patients with high grade disease with a very high Ki67 index (greater than 80 per cent) to have a better survival than those with a lower index (less than 80 per cent). The patients with high grade disease who achieved complete remission or good partial remission and had a Ki67 index of less than 80 per cent were more likely to relapse than those with an index of greater than 80 per cent (p less than 0.04). These findings could not be explained by the effect of other prognostic factors such as age, stage, or serum albumin. While the use of Ki67 immunostaining has potential drawbacks, it appears to be a simple and reproducible method of determining a tumour proliferative index which provides relevant clinical data.

The binding of labeled free amino acids to liver and to purified protein by commonly used fixatives was investigated. Glutaraldehyde caused 25% of free leucine to be bound to serum albumin in solution, whereas formaldehyde bound only 0.5%. Liver slices were incubated for 2 min in the presence of labeled leucine and of puromycin, which permits absorption of leucine into the cell but inhibits incorporation into protein. Both counting and radioautographic techniques showed that glutaraldehyde bound 30 times, and osmic acid six times, as much free amino acid as did formaldehyde. By comparing liver slices incubated with and without puromycin for 2 min, it was calculated that in radioautographs prepared after fixation with glutaraldehyde, osmic acid, or formaldehyde 63, 25, and 4% respectively of the grains were due to binding of free amino acid. Formaldehyde, freshly prepared from paraformaldehyde, gives good preservation and is the recommended fixative for radioautography. When levels of free substrate in a tissue are high at the time fixative is added, the amount of binding of free substrate induced by the fixative should be included as a control in radioautographic experiments.

The substantial prevalence of malnutrition in the hospitalized patient population has only been recently recognized. Preoperative nutritional and immunological assessment was performed prospectively on admission in 64 consecutive surgical patients. Factors measured included weight loss, triceps skinfold, midarm muscle circumference, creatinine-height index, serum albumin level, serum transferrin level, total lymphocyte count, serum complement level, serum immunoelectrophoresis, lymphocyte T rosettes formation, neutrophil migration, and delayed hypersensitivity. Using these criteria for malnutrition, 97% of the patients had at least one abnormal measurement and 35% had at least three abnormal measurements. Patients were monitored for complications during their hospital course. Serum albumin level, serum transferrin level, and delayed hypersensitivity reactions were the only accurate prognostic indicators of postoperative morbidity and mortality. Substantial unrecognized malnutrition exists in the surgical patient population. An isolated indicator of malnutrition should be interpreted with caution. The visceral protein compartment (serum albumin and serum transferrin levels and delayed hypersensitivity) is the most accurate prognostic indicator of postoperative morbidity and mortality. Perioperative nutritional support may reduce operative morbidity and mortality in the malnourished operative candidate.

OBJECTIVE

The value of neutrophil-gelatinase-associated lipocalin (NGAL), a novel biomarker in the detection of acute renal failure in children after cardiac surgery, has been highlighted in previous studies. The incidence of percutaneous coronary intervention (PCI) increases, which may possibly result in increased incidences of contrast nephropathy, its potentially serious complication. Therefore, the aim of our study was to assess prospectively NGAL in patients undergoing elective PCI in relation to serum creatinine.

METHODS

NGAL was assessed in the serum and urine using commercially available kits.

RESULTS

We measured urinary and serum NGAL before, and 2, 4, 12, 24 and 48 h after PCI. We found a significant rise in serum NGAL 2 and 4 h after PCI, and a rise in urinary NGAL 4 and 12 h after PCI. Before PCI, serum NGAL was significantly associated with serum creatinine, urea, urinary NGAL, hemoglobin, hematocrit, albumin, age and presence of diabetes. In multivariate analysis, serum creatinine was the only predictor of serum NGAL. Serum NGAL 2 h after PCI correlated with serum creatinine, duration of PCI, HbA1c, hematocrit, hemoglobin and urinary NGAL. In multivariate analysis, the only predictors of serum NGAL 2 h after PCI were serum creatinine, time of PCI and HbA1c. Serum NGAL before PCI was significantly higher in diabetics than in non-diabetics.

CONCLUSIONS

NGAL may represent a sensitive early biomarker of renal impairment after PCI. Serum creatinine, duration of PCI, but not type and amount of contrast agent, and appropriate treatment of diabetes, reflected by HbA1c, predict a rise in serum NGAL and kidney function following PCI.

The rate of hepatic metabolism of dimethylaminoantipyrine (aminopyrine), which occurs primarily through N-demethylation, was assessed by measurement of the specific activity of 14CO2 excreted in breath samples obtained 2 hours after oral administration of a trace dose of [14C]aminopyrine. The percentage of administered 14C excreted in 14CO2 in 2 hours was 7.0 +/- 1.3 (SD)% in control patients, and significantly less (P less than 0.01) in patients with portal cirrhosis (2.6 +/- 1.2%), fatty liver (4.7 +/- 1.1%), hepatitis (2.6 +/- 1.4%), and hepatic malignancy (3.5 +/- 1.8%). In 16 of 24 subjects with cholestasis not caused by malignant disease the mean 14CO2 excretion was normal. The 14CO2 excretion in patients with portal cirrhosis correlated highly with aminopyrine metabolic clearance rate (r equals 0.92), serum albumin (r equals 0.75), and retention of bromsulphalein (r equals 0.73). Abnormal 14CO2 excretion returned to normal in patients with hepatitis, when the hepatitis resolved. The data suggest that the aminopyrine breath test is a safe, simple, qualitative and quantitative liver function test.

A method for the determination of cross sections for gas-phase protein ions, based on the energy loss of ions as they pass through a collision gas, is described. A simple model relates the energy loss to the number of collisions and hence the cross section. Results from a Monte Carlo model that support the validity of this approach are described. Experimental cross sections are reported for motilin, ubiquitin, cytochrome c, myoglobm, and bovine serum albumin. Cross sections range from approximately 800 Å(2) for motilin to approximately 14,000 Å(2) for bovine serum albumin and generally increase with the number of charges on the ion. Cytochrome c ions from aqueous solution show somewhat smaller cross sections than ions formed from solutions of higher organic content, suggesting that the gas-phase ions may retain some memory of their solution conformation.

The protective effect of intravenously administered rabbit antitoxin serum was studied in lethal Pseudomonas aeruginosa burn infections in mice. Survival after infection with 2 median lethal doses of a toxigenic, low-protease-producing strain (PA103) was enhanced in antitoxin-treated mice, as compared with controls that had received anti-bovine serum albumin serum (P = 0.0004). Survival time was prolonged in other antitoxin-treated mice infected with toxigenic, high-protease-producing strains (PA86 and PA220, P = 0.0003 and P = 0.01, respectively). In contrast, antitoxin had no protective effect in mice challenged with a nontoxigenic strain (WR 5, P = 0.57). There were fewer viable bacteria in blood and liver of antitoxin-treated mice than in those of anti-bovine serum albumin-treated controls after infection with toxigenic organisms, whereas there were no significant differences between the two groups after challenge with the nontoxigenic strain. These data suggest that P. aeruginosa exotoxin A contributes to lethality in this burn infection model, and this effect is diminished by passive immunization with antitoxin.

This paper compares the physicochemical properties of six low molecular weight clinical complexes of gadolinium studied under identical experimental conditions. Magnevist, Dotarem, Omniscan, ProHance, MultiHance and Gadovist were investigated by oxygen-17 relaxometry at different temperatures and by proton relaxometry at various magnetic fields, temperatures and media [pure water, zinc(II)-containing aqueous solutions and HSA-containing solutions]. Osmolality, viscosity and stability versus transmetallation by zinc(II) ions were added for a more comprehensive description. The relaxivities of the clinical formulations as measured in water are similar in the imaging magnetic field region, with a slightly better performance for MultiHance. This can be explained by a shorter distance between the hydrogen nuclei of the water molecule bound to the Gd(3+) ion and this paramagnetic centre. In contrast to the open-chain complexes, all macrocyclic systems (Dotarem, ProHance and Gadovist) are insensitive to transmetallation by zinc ions. The stability of the open-chain complexes with respect to transmetallation depends on the chemical structure of the ligand, with a better stability for MultiHance. The presence of human serum albumin has no significant effect on the proton relaxivity of Magnevist, Dotarem, Omniscan, ProHance and Gadovist but markedly increases the relaxivity of MultiHance because of a non-covalent interaction with the protein. As a result, the relaxivity of MultiHance in HSA-containing media of fixed concentration decreases with increasing concentration of the contrast agent.

BACKGROUND

Cancer incidence is increasing in the United Kingdom, as well as on a global basis. Biochemical parameters, such as C-reactive protein and albumin (combined to form the modified Glasgow Prognostic Score, mGPS), alkaline phosphatase (Alk phos), gamma-glutamyl transferase (GGT) and serum calcium have been reported to be associated with cancer and non-cancer mortality. Therefore, to definitively examine the interrelationships between the above biochemical parameters, the mGPS and the presence of cancer, the Glasgow Inflammation Outcome Study was undertaken. The aim of this initial study was to examine the effect of cancer on markers of systemic inflammation induced by the liver (mGPS) and on levels of routine biochemical parameters.

METHODS

Patients (n=223 303) who had a single incidental sample taken for C-reactive protein, albumin, calcium and serum liver function tests where available, between 2000 and 2008 were studied. Those with a pathological diagnosis of cancer (n=22 715) were identified. The mGPS was constructed and liver function tests classified in accordance with the local reference ranges.

RESULTS

Patients with cancer had higher C-reactive protein and lower albumin levels (and thus a higher mGPS), higher adjusted calcium, Alk phos and GGT levels, but lower aspartate transaminase (AST) and alanine transaminase (ALT) levels (all P<0.001). The strongest associations (Spearman's correlation>> or =0.3) in both the non-cancer and cancer groups were found between albumin, C-reactive protein and Alk phos, AST and ALT, AST and GGT and ALT and GGT (all P<0.001). On multivariate analysis, the associations with the presence of cancer remained with age, deprivation, C-reactive protein, albumin, adjusted calcium, Alk phos and GGT (all P<0.01). Patients following a diagnosis of cancer had lower albumin levels and thus higher mGPS (all P<0.001). Also, post-diagnosis patients were more likely to have lower adjusted calcium, bilirubin, Alk Phos, AST, ALT and GGT levels (all P<0.05). When the cancer diagnoses were ranked from those with the lowest proportion of mGPS 1 or 2 to those with the highest, the percentage of cases with a mGPS of 1 or 2 ranged from 21% in breast cancer to 46% in prostate cancer and to 68% in pulmonary cancer. Compared with breast cancer the mGPS was significantly higher in those diagnosed with dermatological, bladder, endocrinological, gynaecological, prostate, musculoskeletal, gastroesophageal, haematological, renal, colorectal, head and neck, pancreaticobiliary and pulmonary cancers (all P<0.001).

CONCLUSIONS

The results of the present study indicate that the systemic inflammatory response is common in a large patient cohort, increased by the presence of cancer and associated with the perturbation of a number of biochemical parameters previously reported to be associated with mortality. There is a striking parallel between the proportions of cases with a mGPS of 1 or 2 and reported survival rates in these tumours.

A mathematic model that described the acid-base behavior of blood plasma has been revised to incorporate pK values of individual histidine residues on human serum albumin determined by nuclear magnetic resonance spectroscopy. With the insights derived from the model a method for evaluation of the strong ion difference has been developed. Thus if pH, PCO2, and the concentrations of serum albumin and phosphate are measured, all independent variables, which physically determine "acid-base balance" in plasma, can be quantified. New ways to evaluate "unidentified anions" in metabolic acidosis can be explored with this approach.

In this double-blind crossover study, the effects of bolus infusions of 0.9% saline (NaCl) and Hartmann's solution on serum albumin, haematocrit and serum and urinary biochemistry were compared in healthy subjects. Nine young adult male volunteers received 2-litre intravenous infusions of 0.9% saline and Hartmann's solution on separate occasions, in random order, each over 1 h. Body weight, haematocrit and serum biochemistry were measured pre-infusion and at 1 h intervals for 6 h. Biochemical analysis was performed on pooled post-infusion urine. Blood and plasma volume expansion, estimated by dilutional effects on haematocrit and serum albumin, were greater and more sustained after saline than after Hartmann's solution (P <0.01). At 6 h, body weight measurements suggested that 56% of the infused saline was retained, in contrast with only 30% of the Hartmann's solution. Subjects voided more urine (median: 1,000 compared with 450 ml) of higher sodium content (median: 122 compared with 73 mmol) after Hartmann's than after saline (both P =0.049), despite the greater sodium content of the latter. The time to first micturition was less after Hartmann's than after saline (median: 70 compared with 185 min; P =0.008). There were no significant differences between the effects of the two solutions on serum sodium, potassium, urea or osmolality. After saline, all subjects developed hyperchloraemia (>105 mmol/l), which was sustained for >6 h, while serum chloride concentrations remained normal after Hartmann's (P <0.001 for difference between infusions). Serum bicarbonate concentration was significantly lower after saline than after Hartmann's (P =0.008). Thus excretion of both water and sodium is slower after a 2-litre intravenous bolus of 0.9% saline than after Hartmann's solution, due possibly to the more physiological [Na(+)]/[Cl(-)] ratio in Hartmann's solution (1.18:1) than in saline (1:1) and to the hyperchloraemia caused by saline.

The purpose of this study was to evaluate the efficacy of a vaccine consisting of the O-polysaccharide of the lipopolysaccharide (LPS) of Francisella tularensis chemically conjugated to bovine serum albumin. The results show that conjugation preserved both the antigenicity and immunogenicity of the polysaccharide moiety. Mice vaccinated with the glyco-conjugate, but not with BSA alone, were completely protected against an intradermal challenge with a highly virulent type B strain of F. tularensis, and partially protected against an aerosol challenge with the same strain. However, such vaccination failed to protect against an aerosol challenge with a virulent type A strain of the pathogen. The results suggest that the O-antigen of F. tularensis could be considered as a potential component of a subunit vaccine against type B, but not type A strains of F. tularensis.