The last five years have witnessed a remarkable renaissance in vitamin D research and a complete re-evaluation of its benefits to human health. Two key factors have catalyzed these changes. First, it now seems likely that localized, tissue-specific, conversion of 25-hydroxyvitamin D (25OHD) to 1,25-dihydroxyvitamin D (1,25(OH)2D) drives many of the newly recognized effects of vitamin D on human health. The second key factor concerns the ongoing discussion as to what constitutes adequate or optimal serum vitamin D (25OHD) status, with the possibility that vitamin D-deficiency is common to communities across the globe. These two concepts appear to be directly linked when low serum concentrations of 25OHD compromise intracrine generation of 1,25(OH)2D within target tissues. But, is this an over-simplification? Pro-hormone 25OHD is a lipophilic molecule that is transported in the circulation bound primarily to vitamin D binding protein (DBP). While the association between 25OHD and DBP is pivotal for renal handling of 25OHD and endocrine synthesis of 1,25(OH)2D, what is the role of DBP for extra-renal synthesis of 1,25(OH)2D? We hypothesize that binding to DBP impairs delivery of 25OHD to the vitamin D-activating enzyme 1α-hydroxylase in some target cells. Specifically, it is unbound, 'free' 25OHD that drives many of the non-classical actions of vitamin D. Levels of 'free' 25OHD are dependent on the concentration of DBP and alternative serum binding proteins such as albumin, but will also be influenced by variations in DBP binding affinity for specific vitamin D metabolites. The aim of this review will be to discuss the merits of 'free 25OHD' as an alternative marker of vitamin D status, particularly in the context of non-classical responses to vitamin D. This article is part of a Special Issue entitled '16th Vitamin D Workshop'.

OBJECTIVE

To determine whether hypoalbuminemia is an independent risk factor for poor outcome in the acutely ill, and to assess the potential of exogenous albumin administration for improving outcomes in hypoalbuminemic patients.

BACKGROUND

Hypoalbuminemia is associated with poor outcomes in acutely ill patients, but whether this association is causal has remained unclear. Trials investigating albumin therapy to correct hypoalbuminemia have proven inconclusive.

METHODS

A meta-analysis was conducted of 90 cohort studies with 291,433 total patients evaluating hypoalbuminemia as an outcome predictor by multivariate analysis and, separately, of nine prospective controlled trials with 535 total patients on correcting hypoalbuminemia.

RESULTS

Hypoalbuminemia was a potent, dose-dependent independent predictor of poor outcome. Each 10-g/L decline in serum albumin concentration significantly raised the odds of mortality by 137%, morbidity by 89%, prolonged intensive care unit and hospital stay respectively by 28% and 71%, and increased resource utilization by 66%. The association between hypoalbuminemia and poor outcome appeared to be independent of both nutritional status and inflammation. Analysis of dose-dependency in controlled trials of albumin therapy suggested that complication rates may be reduced when the serum albumin level attained during albumin administration exceeds 30 g/L.

CONCLUSIONS

Hypoalbuminemia is strongly associated with poor clinical outcomes. Further well-designed trials are needed to characterize the effects of albumin therapy in hypoalbuminemic patients. In the interim, there is no compelling basis to withhold albumin therapy if it is judged clinically appropriate.

Many neurological diseases are accompanied by increased protein concentrations in the cerebrospinal fluid (CSF), described as a blood-CSF barrier dysfunction. The earlier interpretation as a "leakage" of the blood-CSF barrier for serum proteins could be revised by introduction of a "population variation coefficient" of the CSF/serum quotients for IgG, IgA and IgM (delta Q/Q) which is evaluated as a function of increasing albumin quotients (QAlb). The data presented here are based on specimens from 4380 neurological patients. These population variation coefficients were found to be constant over two orders of magnitude of normal and pathological CSF protein concentrations (QAlb = 1.6.10(-3)-150.10(-3)). This constancy indicates that there was no change in blood-CSF barrier related structures with respect to diffusion controlled protein transfer from blood into CSF and hence no change in molecular size dependent selectivity. The pathological increase of plasma protein concentrations in CSF in neurological diseases could also be explained quantitatively by a decrease of CSF flow rate due to its bifunctional influence on CSF protein concentration: reduced volume exchange, and as newly stated, increased molecular net flux into CSF without change of permeability coefficients. Again, on the basis of a changing CSF flow rate, the hyperbolic functions, which describe empirically the changing quotient ratios between proteins of different size (e.g. QIgG:QAlb) with increasing CSF protein content (QAlb) can likewise be derived from the laws of diffusion as the physiologically relevant description. The hyperbolic discrimination line between brain-derived and blood-derived protein fractions in CSF in the quotient diagrams for CSF diagnosis can be further improved on the basis of the large number of cases investigated. Other physiological and pathological aspects, such as high CSF protein values in the normal newborn, in spinal blockade, in meningeal inflammatory processes, CNS leukemia or polyradiculitis as well as animal species dependent variations can each be interpreted as due to a difference or change in the CSF flow rate.

Minimal-change disease (MCD) counts for 10 to 15% of cases of primary nephrotic syndrome in adults. Few series have examined this disease in adults. A retrospective review was performed of 95 adults who had MCD and were seen at a single referral center. Examined were presenting features, response to daily versus alternate-day steroids, response to second-line agents, relapse patterns, complications of the disease and therapy, presence of acute renal failure (ARF), and outcome data. Sixty-five patients received daily and 23 received alternate-day steroids initially. There were no differences in remissions, time to remission, relapse rate, or time to relapse between daily- and alternate-day-treated patients. More than one quarter of patients were steroid resistant. At least one relapse occurred in 73% of patients; 28% were frequently relapsing. A significant proportion of frequently relapsing patients became steroid dependent. Second-line agents were used for steroid dependence, steroid resistance, or frequent relapses. No single agent proved superior. There were more remissions with second-line agents in steroid-dependent patients compared with steroid-resistant patients, and remissions were more likely to be complete in steroid-dependent patients. ARF occurred in 24 patients; they tended to be older and hypertensive with lower serum albumin and more proteinuria than those without ARF. At follow up, patients with an episode of ARF had higher serum creatinine than those without ARF. Four patients progressed to ESRD. These patients were less likely to have responded to steroids and more likely to have FSGS on repeat renal biopsy. In this referral MCD population, response to daily and alternate-day steroids is similar. Second-line agents give greater response in patients who are steroid dependent. ARF occurs in a significant number of adult MCD patients and may leave residual renal dysfunction. Few patients progress to ESRD.

OBJECTIVE

To compare the serum-ascites albumin gradient to the exudate-transudate concept in the classification of ascites.

METHODS

Prospective collection of ascitic fluid data from patients with well-characterized causes of ascites.

METHODS

Hepatology inpatient and outpatient ward and consult service of a large, urban hospital.

METHODS

A total of 901 paired serum and ascitic fluid samples were collected from consecutive patients with all forms of ascites.

METHODS

None.

METHODS

The utility of the serum-ascites albumin gradient and the old exudate-transudate concept (as defined by ascitic fluid total protein concentration [AFTP]) were compared for their ability in discriminating the cause for ascites formation.

RESULTS

The albumin gradient correctly differentiated causes of ascites due to portal hypertension from those that were not due to portal hypertension 96.7% of the time. The AFTP, when used as defined in the old exudate-transudate concept, classified the causes of ascites correctly only 55.6% of the time. This resulted in part because the AFTP of most spontaneously infected samples (traditionally expected to be exudates) was low, and the AFTP of most cardiac ascites samples (traditionally expected to be transudates) was high.

CONCLUSIONS

The exudate-transudate concept should be discarded in the classification of ascites. The serum-ascites albumin gradient is far more useful than the AFTP as a marker for portal hypertension, but the latter remains a useful adjunct in the differential diagnosis of ascites.

This review aims to provide an extensive overview of the literature on the clinical pharmacokinetics of mycophenolate in solid organ transplantation and a briefer summary of current pharmacodynamic information. Strategies are suggested for further optimisation of mycophenolate therapy and areas where additional research is warranted are highlighted. Mycophenolate has gained widespread acceptance as the antimetabolite immunosuppressant of choice in organ transplant regimens. Mycophenolic acid (MPA) is the active drug moiety. Currently, two mycophenolate compounds are available, mycophenolate mofetil and enteric-coated (EC) mycophenolate sodium. MPA is a potent, selective and reversible inhibitor of inosine monophosphate dehydrogenase (IMPDH), leading to eventual arrest of T- and B-lymphocyte proliferation. Mycophenolate mofetil and EC-mycophenolate sodium are essentially completely hydrolysed to MPA by esterases in the gut wall, blood, liver and tissue. Oral bioavailability of MPA, subsequent to mycophenolate mofetil administration, ranges from 80.7% to 94%. EC-mycophenolate sodium has an absolute bioavailability of MPA of approximately 72%. MPA binds 97-99% to serum albumin in patients with normal renal and liver function. It is metabolised in the liver, gastrointestinal tract and kidney by uridine diphosphate gluconosyltransferases (UGTs). 7-O-MPA-glucuronide (MPAG) is the major metabolite of MPA. MPAG is usually present in the plasma at 20- to 100-fold higher concentrations than MPA, but it is not pharmacologically active. At least three minor metabolites are also formed, of which an acyl-glucuronide has pharmacological potency comparable to MPA. MPAG is excreted into the urine via active tubular secretion and into the bile by multi-drug resistance protein 2 (MRP-2). MPAG is de-conjugated back to MPA by gut bacteria and then reabsorbed in the colon. Mycophenolate mofetil and EC-mycophenolate sodium display linear pharmacokinetics. Following mycophenolate mofetil administration, MPA maximum concentration usually occurs in 1-2 hours. EC-mycophenolate sodium exhibits a median lag time in absorption of MPA from 0.25 to 1.25 hours. A secondary peak in the concentration-time profile of MPA, due to enterohepatic recirculation, often appears 6-12 hours after dosing. This contributes approximately 40% to the area under the plasma concentration-time curve (AUC). The mean elimination half-life of MPA ranges from 9 to 17 hours. MPA displays large between- and within-subject pharmacokinetic variability. Dose-normalised MPA AUC can vary more than 10-fold. Total MPA concentrations should be interpreted with caution in patients with severe renal impairment, liver disease and hypoalbuminaemia. In such individuals, MPA and MPAG plasma protein binding may be altered, changing the fraction of free MPA available. Apparent oral clearance (CL/F) of total MPA appears to increase in proportion to the increased free fraction, with a reduction in total MPA AUC. However, there may be little change in the MPA free concentration. Ciclosporin inhibits biliary excretion of MPAG by MRP-2, reducing enterohepatic recirculation of MPA. Exposure to MPA when mycophenolate mofetil is given in combination with ciclosporin is approximately 30-40% lower than when given alone or with tacrolimus or sirolimus. High dosages of corticosteroids may induce expression of UGT, reducing exposure to MPA. Other co-medications can interfere with the absorption, enterohepatic recycling and metabolism of mycophenolate. Most pharmacokinetic investigations of MPA have involved mycophenolate mofetil rather than EC-mycophenolate sodium therapy. In population pharmacokinetic studies, MPA CL/F in adults ranges from 14.1 to 34.9 L/h (ciclosporin co-therapy) and from 11.9 to 25.4 L/h (tacrolimus co-therapy). Patient bodyweight, serum albumin concentration and immunosuppressant co-therapy have a significant influence on CL/F. The majority of pharmacodynamic data on MPA have been obtained in patients receiving mycophenolate mofetil therapy in the first year after kidney transplantation. Low MPA AUC is associated with increased incidence of biopsy-proven acute rejection. Gastrointestinal adverse events may be dose related. Leukopenia and anaemia have been associated with high MPA AUC, trough concentration and metabolite concentrations in some, but not all, studies. High free MPA exposure has been identified as a risk factor for leukopenia in some investigations. Targeting a total MPA AUC from 0 to 12 hours (AUC12) of 30-60 mg.hr/L is likely to minimise the risk of acute rejection and may reduce toxicity. IMPDH monitoring is in the early experimental stage. Individualisation of mycophenolate therapy should lead to improved patient outcomes. MPA AUC12 appears to be the most useful exposure measure for such individualisation. Limited sampling strategies and Bayesian forecasting are practical means of estimating MPA AUC12 without full concentration-time profiling. Target concentration intervention may be particularly useful in the first few months post-transplant and prior to major changes in anti-rejection therapy. In patients with impaired renal or hepatic function or hypoalbuminaemia, free drug measurement could be valuable in further interpretation of MPA exposure.

We previously reported that granulocytes are able to produce superoxide (O(2) (-)), a highly reactive compound formed by the one-electron reduction of oxygen. The demonstration of O(2) (-) production was based on the observation that the reduction of extra-cellular cytochrome c by granulocytes was greatly diminished by superoxide dismutase, an enzyme catalyzing the conversion of O(2) (-) to hydrogen peroxide and oxygen. In the present report, studies concerning the effect of bacteria and serum on O(2) (-)-dependent cytochrome c reduction by granulocytes are described.In the absence of bacteria, the O(2) (-)-dependent reduction of extracellular cytochrome c by granulocytes under optimal assay conditions amounted to 9.2+/-2.8 SD nmol/3 x 10(6) cells/20 min. When bacteria (100 organisms/cell) were present, the O(2) (-)-dependent cytochrome c reduction under otherwise similar conditions increased by a factor of nearly four (34.5+/-9.4). There was no effect of albumin or catalase on cytochrome c reduction, and boiled dismutase had only a small effect. Omission of granulocytes or substitution of live cells by cells by cells killed by heat abolished O(2) (-)-dependent cytochrome c reduction. Bacteria killed by autoclaving were almost as effective as live bacteria in stimulating granulocyte O(2) (-) production. Measurements of particle uptake and O(2) uptake by granulocytes indicated that superoxide dismutase did not affect granulocyte metabolism nonspecifically, supporting the conclusion that the diminution of cytochrome c reduction in the presence of dismutase was due to the destruction of O(2) (-) by this enzyme. Stimulation of O(2) (-) production by bacteria was strongly dependent on the presence of serum in the incubation mixture. Serum heated to 56 degrees C for 45 min was as effective as unheated serum in stimulating O(2) (-) production in the presence of bacteria, but boiled serum had no effect. Other experiments suggested that incubation of bacteria with serum resulted in the release of a nonparticulate heat-labile substance capable of stimulating O(2) (-) production in the absence of bacteria. Certain characteristics of the O(2) (-)-dependent cytochrome c reduction by granulocytes were studied, including the dependence of this process on granulocyte, cytochrome c, and bacterial concentrations. In addition, O(2) (-)-dependent cytochrome c reduction was followed as a function of time. A constant rate was found with resting granulocytes. With bacteria the time course was more complex. A well-defined lag was followed by a fairly brief period of extremely vigorous cytochrome c reduction. During this period, the maximum rate of cytochrome c reduction exceeded the rate observed in the absence of bacteria by a factor of 12. The rate then decreased until by 40 min, it had slowed to the rate observed in the absence of bacteria. From the above results, it was concluded that the exposure of the granulocyte to bacteria plus serum initiates a process in which a defined quantity of O(2) (-) is formed in a rapid burst lasting 20-30 min. It is conceivable that the O(2) (-) generated by this process may be involved in the killing of bacteria by the granulocytes.

Ion-exchange calcium electrodes represent the first practical method for the direct measurement of ionized calcium [Ca(++)] in biologic fluids. Using both "static" and "flow-through" electrodes, serum [Ca(++)] was within a rather narrow range: 0.94-1.33 mmoles/liter (mean, 1.14 mmoles/liter). Within a given individual, [Ca(++)] varied only about 6% over a several month period. Consistent pH effects on [Ca(++)] were observed in serum and whole blood, [Ca(++)] varying inversely with pH. Less consistent pH effects were also noted in ultrafiltrates, believed to largely represent precipitation of certain calcium complexes from a supersaturated solution. Heparinized whole blood [Ca(++)] was significantly less than in corresponding serum at normal blood pH, related to the formation of a calcium-heparin complex. [Ca(++)] in ultrafiltrates represented a variable fraction (66.7-90.2%) of total diffusible calcium. There was no apparent correlation between serum ionized and total calcium concentrations. Thus, neither serum total calcium nor total ultrafiltrable calcium provided a reliable index of serum [Ca(++)]. Change in serum total calcium was almost totally accounted for by corresponding change in protein-bound calcium [CaProt]. About 81% of [CaProt] was estimated to be bound to albumin and about 19% to globulins. From observed pH, serum protein, and [CaProt] data, a nomogram was developed for estimating [CaProt] without ultrafiltration. Data presented elsewhere indicate that calcium binding by serum proteins obeys the mass-law equation for a monoligand association. This was indicated in the present studies by a close correspondence of observed serum [Ca(++)] values with those predicted by the McLean-Hastings nomogram. While these electrodes allow study of numerous problems not possible previously, they have not been perfected to the same degree of reliability obtainable with current pH electrodes. The commercial (Orion flow-through) electrode is: (a) expensive. (b) requires periodic replacement of membranes, and (c) has not yet been thermostated. As with blood pH measurements. (d) electrode response is logarithmic, i.e. small potential errors generate rather large [Ca(++)] errors. (e) loss of CO(2) should be prevented, and (f) errors due to other cations must be considered under certain conditions. Despite these limitations, we believe the electrode represents a major advance in calcium metabolism.

OBJECTIVE

Several peripheral blood markers of inflammation have demonstrated prognostic ability, but the value of combining multiple markers as a measure of inflammatory burden remains unknown. The objective of this study was to determine the prognostic value of combining four peripheral blood measures of inflammation in healthy older persons.

METHODS

Inception cohort study with 7 years of follow-up.

METHODS

Three communities.

METHODS

Eight hundred seventy high-functioning subjects aged 70 to 79 who had serum albumin, cholesterol, interleukin (IL)-6, and C-reactive protein (CRP) levels measured at baseline.

METHODS

Three- and 7-year mortality and Rosow- Breslau functional decline.

RESULTS

A summary score was created that assigned one point each for the following blood levels: albumin <3.8 g/dL, cholesterol <170 mg/dL (bottom decile), IL-6>3.8 pg/mL (top tertile), and CRP>2.65 mg/L (top tertile). By 3 years, 6% of subjects had died, and, by 7 years, 23% had died. In subjects with three or four markers of inflammation, the adjusted odds ratios (AORs) for 3- and 7-year mortality were 6.6 and 3.2, respectively, compared with those who had no abnormal markers. Subjects with one or two markers were at more moderate and statistically insignificant increased risk of 3- and 7-year mortality with AORs of 1.5 and 1.3, respectively. The risks for functional decline at 3- and 7-years were generally small (AOR = 1.1-1.9) and not statistically significant.

CONCLUSIONS

In high-functioning older persons, a measure of inflammation can identify those at a much higher risk of mortality and a possibly higher risk of functional decline. Whether therapies directed at reducing inflammation can attenuate such risk remains to be determined.

Serum contains a factor that co-purifies with albumin and causes neurite retraction in PC12 cells, inhibits the proliferation of tumor cells in vitro, and activates the phosphatidylinositol/Ca2+ second messenger system in Xenopus oocytes and other cells. The activity of serum albumin depends on several lysophospholipids bound to albumin. Thin layer chromatographic analysis of the lipids extracted by methanol from serum albumin revealed over a dozen components, several of which evoked oscillatory currents in oocytes. In contrast to serum albumin, most of these lipids were absent in plasma, which lacks the biological activity. The most abundant naturally occurring active component was identified as stearoyl-lysophosphatidic acid. Synthetically prepared lysophosphatidates reproduced the biological activities of the natural serum factor. Adding synthetic lysophosphatidates to inactive fatty acid-free albumin restored activity to the albumin, making the active factor nondialyzable against aqueous solvents and protecting against digestion by various lipases. Since the biologically active lysophosphatidates were produced during blood clotting, in the presence of platelets, and lysophosphatidates have been shown previously to activate platelets, we propose that lysophosphatidates may play an important role in linking platelet activation to receptor-mediated tissue regeneration.

BACKGROUND

Osteoprotegerin (OPG) is a decoy receptor for OPG ligand (OPGL), or receptor activator of NF-kappaB ligand (RANKL). RANKL/RANK interaction is important in terminal differentiation and activation of osteoclasts. In binding to RANKL, OPG blocks differentiation and activation of osteoclasts. AMGN-0007 is a recombinant OPG construct developed as a potential therapeutic agent in the treatment of bone disease.

METHODS

A randomized, double-blind, double-dummy, active-controlled, single-dose, dose escalation study was conducted to determine the safety and effect on bone resorption of AMGN-0007 in patients with multiple myeloma (n = 28) or breast carcinoma (n = 26) with radiologically confirmed lytic bone lesions. Patients were randomized (3:1 ratio) to receive a single dose of either AMGN-0007 (subcutaneously [SC]) or pamidronate (90 mg intravenously) and were followed for 56 days. Medications or other diseases affecting bone metabolism and chemotherapy within 28 days of dosing were exclusion criteria. Biologic activity of AMGN-0007 was assessed by measurement of the surrogate marker of bone resorption, urinary N-telopeptide of collagen (NTX).

RESULTS

AMGN-0007 caused a rapid, sustained, dose-dependent decrease in NTX/creatinine levels, which was at least comparable to the profile observed with pamidronate. Four serious adverse events were reported, three in breast carcinoma patients: a fracture in the left femur (pamidronate, considered unrelated), extreme fatigue (0.3 mg/kg AMGN-0007, considered unrelated), and congestive heart failure (1.0 mg/kg AMGN-0007, considered by the investigator to be probably related to doxorubicin and radiation therapy); one event occurred in a multiple myeloma patient: Herpes zoster (pamidronate, considered unrelated). Two multiple myeloma patients (1.0 mg/kg AMGN-0007) had albumin-adjusted serum calcium levels of 1.9 mmol/L on Day 8 but without clinical symptoms.

CONCLUSIONS

A single SC dose of AMGN-0007 suppressed bone resorption as indicated by a rapid, sustained, and profound decrease of urinary NTX/creatinine in multiple myeloma and breast carcinoma patients. Changes were comparable to those with pamidronate. AMGN-0007 was well tolerated.

BACKGROUND

Pruritus affects many haemodialysis (HD) patients. In this study, pruritus and its relationship to morbidity, mortality, quality of life (QoL), sleep quality and patient laboratory measures were analysed in >300 dialysis units in 12 countries.

METHODS

Pruritus data were collected from 18 801 HD patients in the Dialysis Outcomes and Practice Patterns Study (DOPPS) (1996-2004). Analyses were adjusted for age, gender, black race, Kt/V, haemoglobin, serum albumin, albumin-corrected serum calcium, serum phosphorus, 13 comorbidities, depression, years on dialysis, country and facility clustering effects.

RESULTS

Moderate to extreme pruritus was experienced by 42% of prevalent HD patients in DOPPS during 2002/2003. Many patient characteristics were significantly associated with pruritus, but this did not explain the large differences in pruritus between countries (ranging from 36% in France to 50% in the UK) and between facilities (5-75%). Pruritus was slightly less common in patients starting HD than in patients on dialysis >3 months. Pruritus in new end-stage renal disease (ESRD) patients likely results from pre-existing conditions and not haemodialysis per se, indicating the need to understand development of pruritus before ESRD. Patients with moderate to extreme pruritus were more likely to feel drained [adjusted odds ratio (AOR) = 2.3-5.2, P < 0.0001] and to have poor sleep quality (AOR = 1.9-4.1, P < or = 0.0002), physician-diagnosed depression (AOR = 1.3-1.7, P < or = 0.004), and QoL mental and physical composite scores 3.1-8.6 points lower (P < 0.0001) than patients with no/mild pruritus. Pruritus in HD patients was associated with a 17% higher mortality risk (P < 0.0001), which was no longer significant after adjusting for sleep quality measures.

CONCLUSIONS

The pruritus/mortality relationship may be substantially attributed to poor sleep quality. The many poor outcomes associated with pruritus underscore the need for better therapeutic agents to provide relief for the 40-50% of HD patients affected by pruritus.

We have used a modified CaMV 35S promoter to direct the expression of chimaeric genes encoding human serum albumin (HSA) in transgenic potato and tobacco plants. To secrete the protein, either the human prepro-sequence or the signal sequence from the extracellular tobacco protein PR-S was used. We demonstrate secretion of HSA with both types of signal sequences in transgenic leaf tissue and in suspension cultures. HSA produced in transgenic potato plants was purified to chromatographic homogeneity. N-terminal amino acid sequence analysis revealed that the processing of the precursor protein was dependent on the type of signal sequence. Expression of the human preproHSA gene lead to partial processing of the precursor and secretion of proHSA. Fusion of HSA to the plant PR-S presequence resulted in cleavage of the presequence at its natural site and secretion of correctly processed HSA that is indistinguishable from the authentic human protein.

Celiotomy in cirrhotic patients is reported to bear a high risk of operative morbidity and mortality. We reviewed 100 consecutive, cirrhotic patients who underwent nonshunt celiotomy. Thirty patients died and major complications occurred in another 30 patients. Hospital mortality rate was 21% in 39 biliary operations, 35% in 26 procedures for peptic ulcer disease, and 55% in nine colectomies . Fifty-two variables were compared between survivors without complication, survivors with complications, and nonsurvivors. A computer-generated, multivariant discriminant analysis yielded an equation predictive of survival. Utilizing coagulation parameters, presence of active infection, and serum albumin, the equation predicted survival with 89% accuracy. In a similar fashion, amount of operative transfusions, absence of postoperative ascites, pulmonary failure, gastrointestinal bleeding, and culture-positive urine predicted survival with 100% accuracy. We conclude that celiotomy in the cirrhotic patient is truly associated with very high morbidity and mortality, and preoperative assessment can predict survival with 89% accuracy.

The objective of this study was to determine the effect of left ventricular (LV) mass, volume, and mass-to-volume ratio on mortality in chronic dialysis patients. The Design was a multicenter, prospective inception cohort study with a median follow-up of 41 months. The Setting was three university-affiliated nephrology units. A total of 433 patients who (1) survived>> 6 months from the start of ESRD therapy and (2) had a technically satisfactory baseline echocardiogram were studied. Measurements included a baseline clinical, laboratory and echocardiographic assessment. LV hypertrophy was present in 74% and LV dilation was present in 36% of patients. In patients with normal cavity volume (< or = 90 mL/m2) and normal systolic function, high LV mass index >> 120 g/m2) and mass-to-volume ratios >> 2.2 g/mL) were independently associated with late mortality >> 2 yr after starting dialysis therapy). After adjusting for baseline age, diabetes, and ischemic heart disease, the relative risk for the former was 3.29 and for the latter was 2.24. Cavity volume was of no prognostic significance in this group. In patients with LV dilation and normal systolic function, high cavity volume >> 120 mL/m2) and low mass-to-volume ratio (< 1.8 mL/m2) were independently associated with late mortality, the relative risk in the former being 17.14 and the latter being 4.27. LV mass index was of no prognostic significance in this group. The baseline echocardiographic classification, based on LV mass and cavity volume, was the strongest predictor of late mortality, after adjusting for age, gender, diabetes mellitus, coronary artery disease, angina pectoris, chronic hypertension, and hemoglobin and serum albumin levels.(ABSTRACT TRUNCATED AT 250 WORDS)

The assembly of the copper sites in cytochrome c oxidase involves a series of accessory proteins, including Cox11, Cox17, and Sco1. The two mitochondrial inner membrane proteins Cox11 and Sco1 are thought to be copper donors to the Cu(B) and Cu(A) sites of cytochrome oxidase, respectively, whereas Cox17 is believed to be the copper donor to Sco1 within the intermembrane space. In this report we show Cox17 is a specific copper donor to both Sco1 and Cox11. Using in vitro studies with purified proteins, we demonstrate direct copper transfer from CuCox17 to Sco1 or Cox11. The transfer is specific because no transfer occurs to heterologous proteins, including bovine serum albumin and carbonic anhydrase. In addition, a C57Y mutant of Cox17 fails to transfer copper to Sco1 but is competent for copper transfer to Cox11. The in vitro transfer studies were corroborated by a yeast cytoplasm expression system. Soluble domains of Sco1 and Cox11, lacking the mitochondrial targeting sequence and transmembrane domains, were expressed in the yeast cytoplasm. Metallation of these domains was strictly dependent on the co-expression of Cox17. Thus, Cox17 represents a novel copper chaperone that delivers copper to two proteins.

BACKGROUND

Haemodialysis (HD) patients with lower body mass index (BMI) have a higher relative mortality risk (RR), irrespective of race. However, only Asian Americans treated with HD have been found to have an elevated RR with higher BMI. Asian Americans on HD are 'healthier' than other race groups (i.e. have better overall survival). We hypothesized that an increased mortality risk might be associated with high BMI in a variety of other 'healthier' subgroups of HD patients.

METHODS

The prospective Dialysis Outcomes and Practice Patterns Study (DOPPS) provided baseline demographic, comorbidity and BMI data on 9714 HD patients in the US and Europe (France, Germany, Italy, Spain, and the UK) from 1996-2000. Using multivariate survival analyses, we evaluated BMI-mortality relationships in HD subpopulations defined by continent, race (black and white), gender, tertiles of severity of illness (based on a score derived from comorbid conditions and serum albumin concentration), age (<45, 45-64,>>or=65), smoking, and diabetic status.

RESULTS

Relative mortality risk decreased with increasing BMI. This was statistically significant (P<0.007) except for the smallest subgroup of patients who were <45 years old and were also in the healthiest tertile of comorbidity. All else equal, BMI <20 was consistently associated with the highest relative mortality risk. Overall a lower relative mortality risk (RR) as compared with BMI 23-24.9, was found for overweight (BMI 25-29.9; RR 0.84, P=0.008), for mild obesity (BMI 30-34.9; RR 0.73, P=0.0003), and for moderate obesity (BMI 35-39.9; RR 0.76, P=0.02).

CONCLUSIONS

In a wide variety of HD patient subgroups, differing with respect to their baseline health status, increasing body size correlates with a decreased mortality risk. This contrasts with the association between BMI and mortality in the general population, and deserves further study.

OBJECTIVE

Ligands and antagonists of the WNT pathway are linked to osteoporosis and osteoarthritis. In particular, polymorphisms in the FRZB gene, a secreted WNT antagonist, have been associated with osteoarthritis. The aim of this study was to examine cartilage and bone in Frzb(-/-) mice.

METHODS

The Frzb gene in mice was inactivated using a Cre/loxP strategy. Three models of osteoarthritis were used: collagenase, papain, and methylated bovine serum albumin induced. Bone biology was studied using density measurements and microfocal computed tomography. Bone stiffness and mechanical loading-induced bone adaptation were studied by compression of the ulnae.

RESULTS

Targeted deletion of the Frzb gene in mice increased articular cartilage loss during arthritis triggered by instability, enzymatic injury, or inflammation. Cartilage damage in Frzb(-/-) mice was associated with increased WNT signaling and matrix metalloproteinase 3 (MMP-3) expression and activity. Frzb(-/-) mice had increased cortical bone thickness and density, resulting in stiffer bones, as demonstrated by stress-strain relationship analyses. Moreover, Frzb(-/-) mice had an increased periosteal anabolic response to mechanical loading as compared with wild-type mice.

CONCLUSIONS

The genetic association between osteoarthritis and FRZB polymorphisms is corroborated by increased cartilage proteoglycan loss in 3 different models of arthritis in Frzb(-/-) mice. Loss of Frzb may contribute to cartilage damage by increasing the expression and activity of MMPs, in a WNT-dependent and WNT-independent manner. FRZB deficiency also resulted in thicker cortical bone, with increased stiffness and higher cortical appositional bone formation after loading. This may contribute to the development of osteoarthritis by producing increased strain on the articular cartilage during normal locomotion but may protect against osteoporotic fractures.

OBJECTIVE

To overview the world literature on ovarian hyperstimulation syndrome (OHSS) and modes of prevention and treatment of OHSS.

METHODS

All the pertinent literature on OHSS, its prevention, and strategies for treatment were reviewed.

CONCLUSIONS

Key to prevention is proper identification of the population at risk, which includes women with either the hormonal or the morphological signs of polycystic ovarian disease, high serum estradiol (E2) before human chorionic gonadotropin (hCG) administration (E2 greater than 4,000 pg/mL), multiple follicular response (greater than 35), younger age, and lean habitus. When a high risk situation is recognized, ovulatory dose of hCG may be reduced, avoided (with cycle cancellation), or substituted by gonadotropin-releasing hormone or its agonist. Luteal support with hCG is to be bypassed. To minimize risk of OHSS, endogenous pregnancy-drived hCG may be eluded by judicious cryopreservation of all embryos. Last, follicular aspiration will allow higher levels of E2 and larger number of follicles to be matured with lesser risk of OHSS than conventional ovulation induction without follicular aspiration.

METHODS

In-house for the severe and intensive care for the critical form. Meticulous fluid and electrolyte balance using both crystalloids and colloids (albumin) until hemoconcentration abates. Paracentesis is indicated for tight ascites, deteriorating kidney functions, and symptomatic relief. Diuretics may be prudently used once hemodilution is achieved. Dopamine drip may be used as a renal rescue, whereas heparin is indicated for thromboembolic phenomena and surgery reserved for abdominal catastrophies. Therapeutic interruption of an early gestation may be lifesaving when all other measures have failed.

CONCLUSIONS

Although severe and critical OHSS may not be completely avoided, early recognition of high-risk factors, judicious prevention schemes, and treatment strategies should reduce the complication and long-term sequelae of this iatrogenic syndrome.

Binding of antigen to IgE-receptor complexes on the surface of RBL-2H3 rat basophilic leukemia cells is the first event leading to the release of cellular serotonin, histamine, and other mediators of allergic, asthmatic, and inflammatory responses. We have used dinitrophenol-conjugated bovine serum albumin (DNP-BSA) as well as the fluorescent antigen, DNP-B-phycoerythrin, and the electron-dense antigen, DNP-BSA-gold, to investigate dynamic membrane and cytoskeletal events associated with the release of [3H]serotonin from anti-DNP-IgE-primed RBL-2H3 cells. These multivalent antigens bind rapidly to cell surface IgE-receptor complexes. Their distribution is initially uniform, but within 2 min DNP-BSA-gold is found in coated pits and is subsequently internalized. Antigen internalization occurs in the presence and absence of extracellular Ca2+. The F-actin content of the detergent-extracted cell matrices analyzed by SDS PAGE decreases during the first 10-30 s of antigen binding and then increases by 1 min to almost double the control levels. A rapid and sustained increase is also observed when total F-actin is quantified by flow cytometry after binding of rhodamine-phalloidin. The antigen-stimulated increase in F-actin coincides with (and may cause) the transformation of the cell surface from a finely microvillous to a highly folded or plicated topography. Other early membrane responses include increased cell spreading and a 2-3-fold increase in the uptake of fluorescein-dextran by fluid pinocytosis. The surface and F-actin changes show the same dependence on DNP-protein concentration as stimulated [3H]serotonin release; and both the membrane responses and the release of mediators are terminated by the addition of the non-cross-linking monovalent ligand, DNP-lysine. These data indicate that the same antigen-stimulated transduction pathway controls both the membrane/cytoskeletal and secretory events. However, the membrane and actin responses to IgE-receptor cross-linking are independent of extracellular Ca2+ and are mimicked by phorbol myristate acetate, whereas ligand-dependent mediator release depends on extracellular Ca2+ and is mimicked by the Ca2+ ionophore A23187.

Specific antibody synthesis in brain could be detected with maximal sensitivity by combining an advanced enzyme immunoassay with a sophisticated evaluation method that involves calculating the ratio between the cerebrospinal fluid (CSF)/serum quotients for specific antibodies (Qspec) and total IgG (QIgG). This Antibody Index (AI = Qspec/QIgG) discriminates between a blood-derived and a pathological, brain-derived specific antibody fraction in CSF and takes into account individual changes in blood/CSF barrier function. For local synthesis of polyclonal IgG in the central nervous system (QIgG greater than QLim), we propose the correction AI = Qspec/QLim (QLim represents that IgG fraction in CSF originating only from blood, calculated from the individual albumin quotient of a single patient). The normal reference range for the AI was between 0.7 and 1.3 (n = 250 control patients for each antibody species). Values of AI greater than or equal to 1.5 indicated a local specific antibody synthesis in the central nervous system. Sensitivity and precision were greatest if we analyzed the virus-specific antibodies in CSF and serum simultaneously with an enzyme immunoassay in continuous concentrations (arbitrary units) instead of titer steps. We have applied the method successfully to antibodies to measles, rubella, herpes simplex, varicella-zoster, human immunodeficiency virus (HIV), and cytomegalovirus, and to anti-Toxoplasma or -Borrelia antibodies. Clinical relevance is demonstrated for an acute zoster virus infection (monospecific response), chronic diseases such as HIV encephalitis with acute opportunistic Toxoplasma infection, and multiple sclerosis (secondary polyspecific response).

Clinical trials with antiangiogenic agents have not been able to validate plasma or serum levels of angiogenesis regulators as reliable markers of cancer presence or therapeutic response. We recently reported that platelets contain numerous proteins that regulate angiogenesis. We now show that accumulation of angiogenesis regulators in platelets of animals bearing malignant tumors exceeds significantly their concentration in plasma or serum, as well as their levels in platelets from non-tumor-bearing animals. This process is selective, as platelets do not take up a proportional amount of other plasma proteins (eg, albumin), even though these may be present at higher concentrations. We also find that VEGF-enriched Matrigel pellets implanted subcutaneously into mice or the minute quantities of VEGF secreted by microscopic subcutaneous tumors (0.5-1 mm(3)) result in an elevation of VEGF levels in platelets, without any changes in its plasma levels. The profile of other angiogenesis regulatory proteins (eg, platelet-derived growth factor, basic fibroblast growth factor) sequestered by platelets also reflects the presence of tumors in vivo before they can be macroscopically evident. The ability of platelets to selectively take up angiogenesis regulators in cancer-bearing hosts may have implications for the diagnosis and management of many angiogenesis-related diseases and provide a guide for antiangiogenic therapies.

Plasma proteins are exposed to oxidants in a variety of circumstances in vivo, such as during tissue injury and inflammation. In this report, the relative susceptibility of each of the major plasma proteins to oxidative modification was assessed by exposing whole plasma to a metal-catalyzed radical generating system and detecting oxidation (protein carbonyl groups) using a novel Western blot immunoassay. Proteins were derivitized with dinitrophenylhydrazine, separated by SDS-gel electrophoresis, and screened with antibodies against dinitrophenyl groups. As little as 1 pmol of protein-associated carbonyls could be detected (100 ng of a 50 kD protein containing 0.5 mol carbonyl/mol protein). Individual plasma proteins were identified by their comigration with standards, crossreactivity with specific antibodies, and by comparison of plasma to serum. Using this approach, we found that plasma fibrinogen was much more susceptible to oxidative modification compared to the other major plasma proteins, albumin, immunoglobulins, and transferrin. The results emphasize the utility of this method for studying oxidation of proteins in cell extracts and tissues and indicate that experiments on the effects of oxidation on fibrinogen function are merited.

OBJECTIVE

To assess whether serum levels of the inflammatory proteins alpha(1)-antichymotrypsin (ACT), C-reactive protein (CRP), interleukin-6 (IL-6), and albumin are associated with cognitive decline in older persons.

METHODS

The study sample consisted of 1,284 participants in the Longitudinal Aging Study Amsterdam, aged 62 to 85 years. Cognition was assessed on general cognition (Mini-Mental State Examination [MMSE]), memory (Auditory Verbal Learning Test), fluid intelligence (Raven's Colored Progressive Matrices), and information-processing speed (Coding Task) at baseline and at 3-year follow-up.

RESULTS

The highest tertile of ACT was associated with an increased risk of decline on the MMSE (age-, sex-, education-adjusted odds ratio [OR] 1.60; 95% CI: 1.05 to 2.43) but not on any other cognitive test score. CRP, IL-6, and albumin were not associated with cognitive decline on any cognitive test in our study.

CONCLUSIONS

This population-based study showed that the serum inflammatory protein alpha1-antichymotrypsin is associated with cognitive decline in older persons, whereas C-reactive protein, interleukin-6, and albumin are not.