Serum albumin

Pneumonia risk stratification in tropical Australia: does the SMART-COP score apply?

OBJECTIVE

To examine the performance in tropical northern Australia of SMART-COP, a simple scoring system developed in temperate Australia to predict the need for intensive respiratory or vasopressor support (IRVS) in pneumonia patients.

DESIGN, SETTING AND PATIENTS

A prospective observational study of patients admitted to Royal Darwin Hospital in the Northern Territory with sepsis between August 2007 and May 2008. Chest x-rays were reviewed to confirm pneumonia, and each patient's SMART-COP score was assessed against the need for IRVS.

RESULTS

Of 206 patients presenting with radiologically confirmed pneumonia, 184 were eligible for inclusion. The mean age of patients was 50.1 years, 65% were Indigenous and 56% were men. Overall, 38 patients (21%) required IRVS, and 18 patients (10%) died by Day 30. A SMART-COP score of >or= 3 had a sensitivity of only 71% for predicting the need for IRVS and 67% for 30-day mortality. As the variables most strongly associated with IRVS were serum albumin level < 35 g/L (odds ratio, 6.8) and Indigenous status (odds ratio, 2.3), we tested a modified scoring system (SMART-COP) that used a higher weighting for albumin and included Indigenous status. A SMART-COP score of >or= 3 had a sensitivity of 97% for IRVS and 100% for 30-day mortality.

CONCLUSIONS

The SMART-COP score underestimates the severity of pneumonia in tropical northern Australia, but can be improved by using locally relevant additions.

Reassessment of albumin as a nutritional marker in kidney disease

The decision by nephrologists, renal dietitians, federal agencies, health care payers, large dialysis organizations, and the research community to embrace serum albumin as an important index of nutrition and clinical performance is based on numerous misconceptions. Patients with analbuminemia are not malnourished and individuals with simple malnutrition are rarely hypoalbuminemic. With the possible exception of kwashiorkor, a rare nutritional state, serum albumin is an unreliable marker of nutritional status. Furthermore, nutritional supplementation has not been clearly shown to raise levels of serum albumin. The use of serum albumin as a quality care index is also problematic. It has encouraged a reflexive reliance on expensive and unproven interventions such as dietary supplements and may lead to adverse selection of healthier patients by health care providers. The authors offer a rationale for considering albumin as a marker of illness rather than nutrition. Viewed in this manner, hypoalbuminemia may offer an opportunity to improve patient well-being by identifying and treating the underlying disorder.

Inflammation in Aging Part 2: Implications for the Health of Older People and Recommendations for Nursing Practice

Aging is accompanied by declining function and remodeling of body systems. In particular, changes to the immune and endocrine systems have far-reaching effects that cause an increase in cytokine release and decrease in anti-inflammatory feedback systems. The chronic inflammation that ensues has been named ‘‘inflammaging.’’ Inflammaging is associated with many detrimental effects that combine to increase morbidity and mortality. The sickness behavior that arises from inflammatory processes and the side effects of chronic diseases lead to a constellation of symptoms that decrease quality of life and affect the well-being of the individual. Part 2 of this two-part article provides an overview of the health effects of inflammaging, addressing the extent to which it contributes to the syndromes of frailty and disability with aging.

Protein and carbohydrate supplementation after exercise increases plasma volume and albumin content in older and young men

This study examined whether increased plasma volume (PV) and albumin content (Alb(cont)) in plasma for 23 h after exercise were attenuated in older subjects compared with in young adult subjects, and if this attenuation abated by supplementation with protein and carbohydrate (CHO) immediately after exercise. Eight moderately active older (approximately 68 yr) and 8 young (approximately 21 yr) men performed two trials: control (CNT) and Pro-CHO in which subjects consumed placebo (0.5 kcal, 0 g protein, 0.5 mg Na(+) in 3.2 ml total fluid volume/kg body wt) or protein and CHO mixture (3.2 kcal, 0.18 g protein, 0.5 mg Na(+) in 3.2 ml total fluid volume/kg body wt) supplementations, respectively, immediately after high-intensity interval exercise for 72 min [8 sets of 4 min at 70-80% peak oxygen consumption rate (Vo(2peak)) intermitted by 5 min at 20% Vo(2peak)]. PV, Alb(cont), and plasma globulin content (Glb(cont)) were measured before exercise, at the end of exercise, every hour from the 1st to the 5th hour after exercise, and at the 23rd hour after exercise. From 12 h before the start to the end of experiment, food intake was controlled to the age-matched recommended dietary allowances. We found that during the first 4 h after exercise in CNT, Alb(cont) recovered less in the older than the young group by approximately 0.04 g/kg (P < 0.05), while it generally recovered more with Pro-CHO than CNT by approximately 0.09 and approximately 0.04 g/kg in the young and older group, respectively, accompanied by a greater increase in PV by approximately 1 and approximately 2 ml/kg, respectively, during the 23 h after exercise (P < 0.05). Glb(cont) remained constant throughout the experiment in both trials for both age groups. Thus the attenuated responses of Alb(cont) and PV after exercise in older subjects were restored by protein and CHO supplementation immediately after exercise, similarly to young subjects.

Hyperalbuminemia associated with hepatocellular carcinoma in a dog

A 12-year-old, neutered male, mixed-breed dog was presented to The Ohio State University Veterinary Teaching Hospital with a history of weight loss and weakness. Laboratory abnormalities reported by the referring veterinarian during the past year included increased alkaline phosphatase (ALP) activity, hyperalbuminemia, and nonregenerative anemia. On referral, the dog appeared hydrated and had moderate muscle wasting and hepatomegaly. A large lobular hepatic mass was observed ultrasonographically. Laboratory results included mild to moderate nonregenerative anemia, urine-specific gravity of 1.035, 3+ proteinuria, increased serum activities of alanine aminotransferase (229 U/L, reference interval 10-55 U/L), ALP (813 U/L, reference interval 15-120 U/L), and the steroid-induced isoform of ALP (676 U/L, reference interval 0-6 U/L), marked hyperalbuminemia (5.3 g/dL, reference interval 2.9-4.2 g/dL), and an increased A/G ratio (1.7). Hyperalbuminemia was confirmed by reanalysis on 2 different analyzers and by agarose gel electrophoresis, and colloid osmotic pressure (COP) was markedly increased (42.5 mmHg, reference interval 20-25 mmHg). Cytologic examination of a fine-needle aspirate of the hepatic mass indicated hepatocellular proliferation; histologic examination of an excisional biopsy confirmed hepatocellular carcinoma. Three weeks after surgery, the albumin concentration, A/G ratio, COP, and ALT activity had normalized, but ALP activities remained high. We hypothesized that hyperalbuminemia developed secondary to hepatocellular carcinoma due to increased synthesis of albumin by malignant hepatocytes or due to decreased negative feedback from impaired hepatocellular osmoreceptivity. Hepatocellular carcinoma has been associated with paraneoplastic secretion of other proteins, but hyperalbuminemia has been reported only once in a human patient and has not previously in dogs.

Alterations in rat serum proteome and metabolome as putative disease markers in sepsis

OBJECTIVES

Despite a decreased mortality from sepsis, the absolute number of sepsis-related deaths has actually increased during the last years. At present, there are no biological markers available that can reliably assist early clinical diagnosis and the prompt initiation of therapy. This study investigated the changes in serum protein expression in a coecal ligature and puncture model of rat sepsis at 12, 24, and 48 hours after the induction of sepsis using differential proteomics.

METHODS

Sixty-two male Wistar rats were randomly assigned to a sepsis group (coecal ligature and puncture; n = 46) or a sham group (n = 16). Surviving rats were killed 12 hour (n = 6), 24 hour (n = 9), or 48 hour (n = 4) after operation, and their serum lysates were subjected to two-dimensional gel electrophoresis and peptide mass fingerprinting. A systematic functional network mapping and molecular pathway analysis were performed using Ingenuity Pathways Analysis.

RESULTS

Septic mortality was 58.7%, but no rat of the sham group was lost. Per gel, an average of 1,082 +/- 10 spots could be discriminated, of which 40 different protein spots were differentially expressed (p < 0.01). From the total of 40, the number of regulated protein spots was 13 (12 hour group) versus 10 (24 hour group) versus 18 (48 hour group). Ingenuity pathways analysis identified 10 of the differential proteins and allocated them to a pathway of tissue inflammation.

CONCLUSIONS

The present study quantitatively detected several proteins differentially expressed in acute sepsis. Since a longer time-period was investigated and compared with previous studies, the results may offer new insights into septic organ dysfunction and altered protein pathways. The horizontal analysis of protein expression arrays and systematic biochemical pathways may represent an important new tool for the clinical assessment of septic conditions and support the development of early sepsis markers.

Physical activity, white blood cell count, and lung cancer risk in a prospective cohort study

Previous studies have suggested that physical activity may lower lung cancer risk. The association of physical activity with reduced chronic inflammation provides a potential mechanism, yet few studies have directly related inflammatory markers to cancer incidence. The relation among physical activity, inflammation, and lung cancer risk was evaluated in a prospective cohort of 4,831 subjects, 43 to 86 years of age, in Beaver Dam, Wisconsin. A total physical activity index was created by summing up kilocalories per week from sweat-inducing physical activities, city blocks walked, and flights of stairs climbed. Two inflammatory markers, WBC count and serum albumin, were measured at the baseline examination. During an average of 12.8 years of follow-up, 134 incident cases of lung cancer were diagnosed. After multivariable adjustment, participants in the highest tertile of total physical activity index had a 45% reduction in lung cancer risk compared with those in the lowest tertile (hazard ratio, 0.55; 95% confidence interval, 0.35-0.86). Participants with WBC counts in the upper tertile (>or=8 x 10(3)/microL) were 2.81 (95% confidence interval, 1.58-5.01) times as likely to develop lung cancer as those with counts in the lowest tertile (<6.4 x 10(3)/microL). Serum albumin was not related to lung cancer risk. There was no evidence that inflammation mediated the association between physical activity and lung cancer risk, as the physical activity risk estimates were essentially unchanged after adjustment for WBC count. Although the potential for residual confounding by smoking could not be eliminated, these data suggest that physical activity and WBC count are independent risk factors for lung cancer.

Biomarkers of liver status in heavy drinkers, moderate drinkers and abstainers

AIMS

Although a wide variety of biomarkers reflecting liver status are known to be influenced by excessive ethanol consumption, the dose-response relationships between ethanol intake and marker changes have remained less understood.

METHODS

Serum gamma-glutamyltransferase (GGT), aspartate aminotransferase (AST), alanine aminotransferase (ALT) activities, and ferritin and albumin protein concentrations were compared in a large population of heavy drinkers (105 men, 28 women), moderate drinkers (781 men, 723 women) and abstainers (252 men, 433 women), who were devoid of apparent liver disease.

RESULTS

In heavy drinkers, serum GGT, AST, ALT, ferritin and albumin were all significantly higher than in moderate drinkers or abstainers (P < 0.001 for all comparisons). The highest incidences of elevated values were found for GGT (62%) followed by AST (53%), ALT (39%), ferritin (34%) and albumin (20%). Serum GGT (P < 0.001), ALT (P < 0.01) and ferritin (P < 0.05) in moderate drinkers were also higher than the levels observed in abstainers. When the study population was further divided into subgroups according to gender, significant differences between moderate drinkers and abstainers in GGT and ALT were noted in men whereas not in women.

CONCLUSIONS

The data demonstrate that biomarkers of alcohol abuse and liver function may respond to even rather low levels of ethanol intake in a gender-dependent manner, which should be implicated in studies on the early-phase interactions of ethanol and the liver and in the definition of normal ranges for such biomarkers.

Serum albumin concentration and waiting list mortality in idiopathic interstitial pneumonia

BACKGROUND

Hypoalbuminemia is a reliable predictor of mortality in patients with various illnesses as well as a predictor of disability and mortality in healthy older adults. The association between hypoalbuminemia and mortality in patients with idiopathic interstitial pneumonia remains unknown. The objective of this study was to examine the relationship between serum albumin concentration and mortality in a large cohort of patients with idiopathic interstitial pneumonia listed for lung transplantation.

METHODS

In patients classified as having idiopathic pulmonary fibrosis who were listed for lung transplantation with the United Network for Organ Sharing between January 1, 2004, and December 31, 2006 (n = 1,269), we studied the relationship between serum albumin concentration at the time of listing and mortality while awaiting transplantation.

RESULTS

Lower serum albumin was associated with increased mortality rate. Patients with lower categories of serum albumin had increased mortality rates before and after multivariable adjustment (p value for linear trend < 0.0001). Analysis with serum albumin as a continuous predictor indicated that the mortality rate increased by 54% with each 0.5 g/dL decrease in serum albumin concentration (95% confidence interval, 32 to 79%).

CONCLUSIONS

Lower serum albumin is strongly and independently associated with higher mortality in patients with idiopathic interstitial pneumonia on transplant waiting lists.

Predicting the outcome of artificial nutrition by clinical and functional indices

OBJECTIVE

Artificial nutrition (AN) is now considered medical therapy and has progressively become one of the mainstays of the different therapeutic options available for home or hospitalized patients, including surgical, medical, and critically ill patients. The clinical relevance of any therapy is based on its efficacy and effectiveness and thus on the improvement of its cost efficiency, i.e., the ability to provide benefits to the patients with minimal wasting of human and financial resources. The aim of the present study was to identify those indices, clinical, functional, or nutritional, that may reliably predict, before the start of AN, those patients who are likely not to benefit from nutritional support.

METHODS

Three hundred twelve clinical charts of patients receiving AN between January 1999 and September 2006 were retrospectively examined. Data registered before starting AN were collected and analyzed: general data (age, sex), clinical conditions (comorbidity, quality of life, frailty), anthropometric and biochemical indices, type of AN treatment (total enteral nutrition, total parenteral nutrition, mixed AN), and outcome of treatment.

RESULTS

The percentage of negative outcomes (death or interruption of AN due to worsening clinical conditions within 10 d after starting AN) was meaningfully higher in subjects >80 y of age and with reduced social functions, higher comorbidity and/or frailty, reduced level of albumin, prealbumin, lymphocyte count, and cholinesterase and a higher level of C-reactive protein. The multivariate analysis showed that prealbumin and comorbidity were the best predictors of AN outcome. The logistic regression model with these variables showed a predictive value equal to 84.2%.

CONCLUSION

Proper prognostic instruments are necessary to perform optimal evaluations. The present study showed that a patient's general status (i.e., comorbidity, social quality of life, frailty) and nutritional and inflammatory statuses (i.e., lymphocyte count, albumin, prealbumin, C-reactive protein) have good predictive value on the effectiveness of AN.

Bloodstream infection after living donor liver transplantation

There are no detailed studies on the prevalence or clinical magnitude of bloodstream infection (BSI) following living donor liver transplantation (LDLT). The study aimed to assess the incidence and analyze the risk factors for BSI after LDLT. Univariate and multivariate analyses were performed to identify the independent risk factors for postoperative BSI. Postoperatively, 26 episodes of BSI occurred in 21 of 242 studied adult patients by median postoperative d 35. Five patients had primary BSI. The source was unknown in 3 patients and an intravascular catheter in 2. The other 16 patients had secondary BSI. Secondary BSI was caused by surgical site infection in 8 patients, followed by intra-abdominal infection in 5, pneumonia in 2, and both surgical site infection and intra-abdominal infection in 1. The most frequent pathogen isolated was MRSA, which was detected in 4 patients. Surveillance culture detected the same isolates prior to BSI in 14 of 26 (50%) episodes. Diabetes mellitus and serum albumin level less than 2.4 g/dl independently predicted postoperative BSI. Perioperatively, screening for and taking actions against pathogen including MRSA should be performed in LDLT patients.

Hypertrophy of mature Xenopus muscle fibres in culture induced by synergy of albumin and insulin

The aim of this study was to investigate effects of albumin and insulin separately as well as in combination on mature muscle fibres during long-term culture. Single muscle fibres were dissected from m. iliofibularis of Xenopus laevis and attached to a force transducer in a culture chamber. Fibres were cultured in a serum-free medium at slack length (mean sarcomere length 2.3 mum) for 8 to 22 days. The medium was supplemented with (final concentrations): (1) bovine insulin (6 nmol/L or 200-600 nmol/L), (2) 0.2% bovine albumin or (3) 0.2% bovine albumin in combination with insulin (120 nmol/L). In culture medium with insulin, 50% of the muscle fibres became in-excitable within 7-12 days, whereas the other 50% were stable. Caffeine contractures of in-excitable muscle fibres produced 80.4 +/- 2.4% of initial peak tetanic force, indicating impaired excitation-contraction (E-C) coupling in in-excitable fibres. In the presence of albumin, all cultured muscle fibres were stable for at least 10 days. Muscle fibres cultured in medium with insulin or albumin exclusively did not hypertrophy or change the number of sarcomeres in series. In contrast, muscle fibres cultured with both albumin and insulin showed an increase in tetanic force and fibre cross-sectional area of 19.6 +/- 2.8% and 32.5 +/- 4.9%, respectively, (means +/- SEM.; P = 0.007) after 16.3 +/- 1.7 days, whereas the number of sarcomeres in series remained unchanged. We conclude that albumin prevents muscle fibre damage and preserves E-C coupling in culture. Furthermore, albumin is important in regulating muscle fibre adaptation by a synergistic action with growth factors like insulin.

Oxidative damage of albumin in advanced liver disease

Albumin has a number of biological functions and the serum albumin level is related to prognosis in advanced liver disease. Oxidative stress is believed to play an important role in the pathogenesis of liver failure. The aim of the present study was to characterize oxidative modification of albumin in patients with various degrees of liver failure and to investigate implications for its binding function. Patients with liver cirrhosis (n=10), acute-on-chronic liver failure (n=8) and healthy controls (n=15) were included in the study. Three fractions of albumin were separated by HPLC according to the redox state of cysteine-34 and detected by fluorescence as well as UV absorption. Carbonyl groups were measured as a marker of oxidative modification in plasma proteins and, by western blotting, on albumin. Progressive oxidative modification of albumin was found with increasing severity of liver failure indicated by an increased content of carbonyl groups and oxidation of cysteine-34. Fluorescence properties of albumin were altered by oxidation and, in patients with acute-on-chronic liver failure, by high plasma levels of bilirubin. This alteration of albumin fluorescence by bilirubin provides evidence for a preferred binding of bilirubin to the fully reduced form of albumin.

Association between Inflammation-Associated Cytokines, Serum Albumins, and Mortality in the Elderly

OBJECTIVE

To investigate the association between serum albumin, prealbumin, various serum inflammation associated-cytokines, and mortality in older geriatric recuperative care patients.

DESIGN

A prospective cohort study.

SETTING

A geriatric rehabilitation unit of a university-affiliated Department of Veterans Affairs hospital.

PARTICIPANTS

Participants were 53 geriatric patients (mean age 78 +/- 7.3, 96% male) admitted to a Geriatric Evaluation and Management (GEM) unit. Patients with documented near-terminal medical disorder, overt infections, and any systemic or localized inflammatory disorders were excluded.

MEASUREMENTS

Inflammation-associated cytokines (IL-8, IL-1beta, IL-6, IL-10, TNF-alpha), albumin, prealbumin, and C-reactive protein were measured at hospital discharge and each subject was then tracked for 1 year.

MAIN RESULTS

By Cox Proportional-Hazards Regression analysis, the strongest predictor of mortality within 6 months of study entry was the serum IL-6. For each log increase in IL-6, there was nearly a 9-fold greater 6-month mortality risk (RR 8.99, 95% CI 1.65 to 49.03). The association between albumin and mortality was no longer significant after controlling for IL-6. There was a strong inverse correlation between IL-6 and both albumin (R2 0.39, P < .001) and prealbumin (R2 0.41, P < .001).

CONCLUSION

Subclinical inflammation appears to be an important factor contributing to low serum albumins in older recuperative care patients and may confound the association between albumin and mortality in this population. More in-depth studies of these associations are warranted.

Localization of polypyrimidine-tract-binding protein is involved in the regulation of albumin synthesis by branched-chain amino acids in HepG2 cells

Long-term supplementation of branched-chain amino acids (BCAA) improves hypoalbuminemia in patients with cirrhosis. Our previous findings have suggested that the binding of polypyrimidine-tract-binding protein (PTB) to rat albumin mRNA attenuates its translation. The aim of the present study was to investigate the role of PTB in the regulation of albumin synthesis by BCAA in human hepatoma cells. HepG2 cells were cultured in a medium containing no amino acids (AA-free medium), a medium containing only 1 amino acid (a BCAA: valine, leucine or isoleucine) or a medium containing all 20 amino acids (AA-complete medium). HepG2 cells cultured in AA-complete medium secreted much more albumin than cells cultured in AA-free medium, with no difference in albumin mRNA levels. In cells cultured in AA-free medium, nuclear export of PTB was observed, and the level of the albumin mRNA-PTB complex was greater than in cells cultured in AA-complete medium. Addition of amino acids stimulated nuclear import of PTB. However, addition of amino acids with rapamycin inhibited the nuclear import of PTB. The addition of leucine, but not of valine or isoleucine, to AA-free medium increased albumin secretion and stimulated the nuclear import of PTB. These data indicate that the mammalian target of rapamycin is involved in the regulation of PTB localization and that leucine promotes albumin synthesis by inhibiting the formation of the albumin mRNA-PTB complex.

Fibronectin is elevated in the cerebrospinal fluid of patients suffering from bacterial meningitis and enhances inflammation caused by bacterial products in primary mouse microglial cell cultures

Toll-like receptors (TLR) play a key role in the recognition of pathogenic organisms. Fibronectin, an extracellular matrix protein, is considered a potent stimulator of the innate immune system through TLR4. In bacterial meningitis, several extracellular matrix proteins and bacterial compounds are elevated in the CSF. For this reason, we hypothesized that these molecules may jointly stimulate the innate immune system and increase neuronal damage in bacterial meningitis. Concentrations of fibronectin were elevated in the CSF of patients suffering from bacterial meningitis, but not in patients with multiple sclerosis, when compared with control patients without CSF abnormalities. In primary cultures of mouse microglial cells, co-administration of fibronectin at concentrations occurring in the CSF in bacterial meningitis (10 microg/mL) with defined TLR agonists [lipopolysaccharide (TLR4), the synthetic lipopeptide tripalmytoyl-cysteinyl-seryl-(lysyl)3-lysine (TLR2) and single-stranded unmethylated cytosine-guanosine oligodesoxynucleotide (TLR9)] led to an additive release of nitric oxide and tumor necrosis factor-alpha when compared with the release elicited by either compound alone. In conclusion, the inflammatory reaction to bacterial compounds can be aggravated by endogenous fibronectin at elevated levels during bacterial CNS infections. This additive or synergistic effect may contribute to neuronal damage during bacterial meningitis.

Effect of rapamycin on hepatocyte function and proliferation induced by growth factors

BACKGROUND

Rapamycin is a specific inhibitor of the mammalian target of rapamycin (mTOR). The effect of rapamycin on proliferation and cellular function was studied in hepatocytes stimulated by hepatocyte growth factor (HGF) or transforming growth factor-alpha (TGFalpha).

METHODS AND RESULTS

When isolated rat hepatocytes were cultured at low density, the addition of HGF or TGFalpha increased DNA synthesis but did not affect albumin or fibrinogen concentrations in the medium. In contrast, in hepatocytes cultured at high density, the albumin and fibrinogen concentrations, but not DNA synthesis, were increased by HGF or TGFalpha. The HGF- or TGFalpha-induced increase in DNA synthesis and in albumin or fibrinogen concentrations was suppressed by the addition of rapamycin, as well as wortmannin, a phosphatidylinositol-3 kinase inhibitor.

CONCLUSION

HGF and TGFalpha stimulate proliferation and function of hepatocytes depending upon the conditions, and rapamycin inhibited these stimulatory effects, possibly by inhibiting the mTOR-dependent signaling pathway.

Inflammation as the key interface of the medical and nutrition universes: a provocative examination of the future of clinical nutrition and medicine

There has been tremendous interest in inflammation by researchers, the medical community, and the lay public. Modulation of injury response is felt to represent a tenuous balance of pro- and anti-inflammatory cytokines. Adverse outcomes may result from severe, sustained, or repeated bouts of inflammation. A critical observation is that nutrition support alone is inadequate to prevent muscle loss during active inflammation. It is necessary to take inflammation into consideration in conducting appropriate nutrition assessment, intervention, and monitoring. A host of medical conditions are actually inflammatory states that have important implications for nutrition care. Multifaceted interventions that may include anti-inflammatory diets, glycemic control, physical activity, appetite stimulants, anabolic agents, anti-inflammatory agents, anticytokines, and probiotics, will be necessary to blunt undesirable aspects of inflammatory response to preserve body cell mass and vital organ functions. Nutrition practitioners can seize this opportunity to be a part of the future medical team that brings highly individualized patient care to the bedside.

Serum albumin as a significant prognostic factor for patients with gastric carcinoma

BACKGROUND

The definition of prognostic factors in gastric carcinoma (GC) remains controversial. The potential of serum albumin as a prognostic factor for GC is emphasized because the technique to measure it is simple as well as being cheap and widely available. Our aim was to define the prognostic role of serum albumin in GC.

METHODS

A cohort treated from January 1987 to December 2002 was studied. Relevant clinical, pathological and therapeutic variables were recorded. Kaplan-Meier and Cox's methods were used to define prognostic factors associated with cancer-related survival.

RESULTS

One thousand and twenty-three patients were included. Serum albumin did impact survival, showing a dose-response effect. This effect was present after adjustment for other prognostic factors, including Tumor-Node-Metastasis (TNM) stage, surgical resection and type of lymphadenectomy. In multivariate analysis, TNM stage [Stage Ia and Ib Hazard Ratio [HR] 1, Stage II HR 1.6 (95% confidence interval [CI], 0.56-4.7), Stage IIIa HR 4.4 (95% CI 1.7-11.3), Stage IIIb HR 5.6 (95% CI 2.6-17.2), Stage IV HR 6.8 (95% CI 2.7-17.5), high albumin HR 1, medium albumin HR 1.2 (95% CI 0.8-1.7), low albumin HR 1.2 (95% CI 0.8-1.8), very low albumin HR 1.8 (95% CI 1.3-2.6), D2 dissection HR 1, D1 dissection HR 1.9 (95% CI 1.3-2.97), and no resection HR 3.7 (95% CI 2.4-5.7)] were the most significant prognostic factors associated to survival (model P = 0.00001).

CONCLUSION

Pretherapeutic serum albumin level is a significant prognostic factor, which should be evaluated along with other well-defined prognostic factors in decisions concerning therapy for GC.

Intracellular nucleotide pools and ratios as tools for monitoring dedifferentiation of primary porcine hepatocytes in culture

The effect of two culture configurations (single collagen gel and double collagen gel) and of two hormones (insulin and glucagon) on the differentiated status and the intracellular nucleotide pools of primary porcine hepatocytes was investigated. The objective was to analyze and monitor the current state of differentiation supported by the two culture modes using intracellular nucleotide analysis. Specific intracellular nucleotide ratios, namely the nucleoside triphosphate (NTP) and the uridine (U) ratio were shown to consistently reflect the state of dedifferentiation status of the primary cells in culture affected by the presence of the two hormones insulin and glucagon. Continuous dedifferentiation of the cells was monitored in parallel by the reduction of the secretion of albumin, and changes in UDP-activated hexoses and UDP-glucuronate. The presence of insulin maintained the differentiated status of hepatocytes for more than 12 days when cultivated under double gel conditions whereas glucagon was less effective. In contrast, cells cultivated in a single gel matrix immediately started to dedifferentiate upon seeding. NTP and U ratios were shown to be more sensitive for monitoring dedifferentiation in culture than the albumin secretion. Their use allowed the generation of an easily applicable NTP-U plot in order to give a direct graphical representation of the current differentiation status of the cultured cells. Moreover, the transition from functional and differentiated hepatocytes to dedifferentiated fibroblasts could be determined earlier by the nucleotide ratios compared to the conventional method of monitoring the albumin secretion rate.

Change of serum albumin and risk of cardiovascular disease and all-cause mortality: Longitudinal Aging Study Amsterdam

The aim of this longitudinal study was to investigate 3-year change in serum albumin concentration as a determinant of incident cardiovascular disease (CVD) and all-cause mortality. Data were from 713 respondents of the Longitudinal Aging Study Amsterdam initially aged 55-85 years. Serum albumin was measured at baseline (1992/1993) and after 3 years. At the 6-year follow-up, incident CVD (among 456 respondents with no prevalent CVD at the 3-year follow-up) and all-cause mortality were ascertained. Overall, 18.9% developed CVD and 10.9% died. After adjustment for potential confounders, a higher level of serum albumin at the 3-year follow-up was associated with a lower risk for incident CVD (relative risk = 0.88, 95% confidence interval (CI): 0.79, 0.98). The risk of incident CVD was 0.88 (95% CI: 0.78, 0.99) per unit (g/liter) increase in change in albumin between 3-year follow-up and baseline. Chronic low serum albumin (<or=43 g/liter at baseline and 3-year follow-up) was not associated with incident CVD (p = 0.22). A clinically relevant decrease in serum albumin (>or=1 standard deviation (2.5 g/liter) between baseline and 3-year follow-up) tended to be associated with a twofold risk (relative risk = 2.00, 95% CI: 0.91, 4.39). For all-cause mortality, no associations were observed. These findings suggest that older persons with a decrease in serum albumin concentration, even within the normal range, might be at increased risk of incident CVD. Change in serum albumin may be used as an early marker for CVD risk.

Prognostic value of serum albumin combined with serum C-reactive protein levels in older hospitalized patients: continuing importance of serum albumin

BACKGROUND AND AIMS

Although both serum albumin and C-reactive protein (CRP) levels are separately recognized as predictors of adverse outcomes in many illnesses, the predictive value of their combination for adverse outcomes has not been evaluated. We therefore sought to examine the prognostic value of serum albumin for in-hospital mortality in the presence or absence of severe inflammation, as indicated by high CRP levels.

METHODS

In this cohort study, we measured serum albumin and CRP levels in 1638 older patients (aged 65 years or older) hospitalized for medical problems, and examined their utility, both separately and in combination, for predicting in-hospital mortality.

RESULTS

In separate analyses of CRP and albumin, both high CRP levels (> or =5 mg/dl) and hypoalbuminemia (<3.5 g/dl) were associated with risk of in-hospital death. After dividing participants into four groups based on CRP and albumin levels (<5 mg/dl CRP and <3.5 mg/dl albumin), subjects with severe inflammation (CRP > or =5 mg/dl) and hypoalbuminemia were associated with an adjusted relative risk (ARR) of 3.8 for in-hospital mortality when compared with the reference (high albumin and low CRP). Even in the absence of severe inflammation, the presence of severe hypoalbuminemia was associated with an ARR of 2.6 for in-hospital mortality, when compared with patients without hypoalbuminemia.

CONCLUSIONS

Both serum CRP and albumin levels are predictors of in-hospital mortality. However, high serum albumin levels may have a protective effect in older patients, regardless of degree of inflammation. Serum albumin levels remain a useful predictor for in-hospital mortality in older hospitalized patients.

All-trans retinoic acid down-regulates human albumin gene expression through the induction of C/EBPbeta-LIP

ATRA (all-trans retinoic acid), which is a major bioactive metabolite of vitamin A and a potent regulator of development and differentiation, mediates down-regulation of the human albumin gene. However, the mechanism of ATRA-mediated down-regulation is not well understood. In the present study, deletion analysis and luciferase assays demonstrate that ATRA causes a marked decrease in the activity of the albumin promoter, the region between nt -367 and -167 from the transcription start site, where C/EBP (CCAAT/enhancer-binding protein)-binding sites are tightly packed, is indispensable for ATRA-mediated down-regulation. ChIP (chromatin immunoprecipitation) assays revealed that in vivo binding of C/EBPalpha to the region markedly decreases upon incubation with ATRA, whereas ATRA treatment marginally increases the recruitment of C/EBPbeta. We found that ATRA has the ability to differentially and directly induce expression of a truncated isoform of C/EBPbeta, which is an LIP (liver-enriched transcriptional inhibitory protein) that lacks a transactivation domain, and to increase the binding activity of C/EBPbeta-LIP to its response element. Overexpression of C/EBPbeta-LIP negatively regulates the endogenous expression of albumin, as well as the activity of the albumin promoter induced by C/EBP transactivators such as C/EBPalpha and full-length C/EBPbeta. In conclusion, we propose a novel model for down-regulation of the albumin gene, in which ATRA triggers an increase in the translation of C/EBPbeta-LIP that antagonizes C/EBP transactivators by interacting with their binding sites in the albumin promoter.

Role of visceral proteins in detecting malnutrition in the elderly

OBJECTIVE

In the clinical practice, visceral proteins are used as indirect markers of protein energy malnutrition (PEM), but their reliability could be reduced with advancing age. The aim of this work is to investigate the reliability of albumin, prealbumin, retinol-binding protein (RBP) and transferrin in evaluating nutritional status in old patients and their relationship with fat-free mass (FFM).

DESIGN

Cross-sectional study.

SETTING

Padua, Italy.

SUBJECTS

In 44 underweight (body mass index < 20 kg/m(2)) (66-97 years) and 69 normal weight or overweight elderly subjects (62-98 years), albumin, prealbumin, transferrin and RBP were determined in the plasma. Body composition and particularly FFM was obtained by dual X-ray absorptiometry. FFM was also expressed as FFM index (FFMI) calculated as FFM divided by height squared. Subjects affected by acute illnesses and inflammatory states were excluded.

RESULTS

Albumin, prealbumin and RBP mean values were significantly lower in underweight subjects. No differences between two groups were found for transferrin. Albumin prealbumin and RBP resulted under the normal range in 55, 25 and 54% of underweight subjects, respectively. Transferrin's values were low in about 40% of underweight and normal weight subjects, respectively. In all subjects, FFMI shows a significant correlation with albumin (r: 0.52), prealbumin (r: 0.64) and RBP (r: 0.57). No correlation between FFMI and transferrin was found.

CONCLUSIONS

Visceral proteins, except for transferrin, seem to be useful indexes in detecting malnutrition in the elderly; low values still in the normal range should also be carefully evaluated because they could suggest a poor nutritional status.

The relationship between albumin, other plasma proteins and variables, and age in the acute phase response after liver resection in man

A large series of plasma albumin (ALB, g/dl) and simultaneous blood and clinical measurements were prospectively performed on 92 liver resection patients, and processed to assess the correlations between ALB, other plasma proteins, additional variables and clinical events. The measurements were performed preoperatively and at postoperative day 1, 3 and 7 in all patients, and subsequently only in those who developed complications or died. In patients who recovered normally ALB was 4.3 +/- 0.4 g/dl (mean +/- SD) preoperatively, 3.7 +/- 0.7 at day 1 and 3, and 3.9 +/- 0.4 at day 7. In patients with complications its decrease was more prolonged. In non-survivors it was 3.4 +/- 0.4 preoperatively, 3.0 +/- 0.4 at day 1, and then decreased further. Regression analysis showed direct correlations between ALB and pseudo-cholinesterase (CHE, U/l, nv 5300-13000), cholesterol (CHOL, mg/dl), iron binding capacity (IBC, mg/dl), prothrombin activity (PA, % of standard reference) and fibrinogen, an inverse correlation with blood urea nitrogen (BUN, mg/dl) for any given creatinine level (CREAT, mg/dl), and weaker direct correlations with hematocrit, other variables and dose of exogenous albumin. An inverse relationship found between ALB and age (AGE, years) became postoperatively (POSTOP) also a function of outcome, showing larger age-related decreases in ALB associated with complications (COMPL: sepsis, liver insufficiency) or death (DEATH). Main overall correlations: CHE = 287.4(2.014)(ALB), r = 0.73; CHOL = 16.5(1.610)(ALB) (1.001)(ALKPH), r = 0.71; IBC = 68.6(1.391)(ALB), r = 0.64; PA = 13.8 + 16.0(ALB), r = 0.51; BUN = 21.3 + 20.2(CREAT) - 6.2(ALB), r = 0.91; ALB = 5.0-0.013(AGE) - {0.5 + 0.003(AGE)( COMPL ) + 0.012(AGE)( DEATH )}( POSTOP ), r = 0.74 [p < 0.001 for each regression and each coefficient; ALKPH = alkaline phosphatase, U/l, nv 98-279, independent determinant of CHOL; discontinuous variables in italics label the change in regression slope or intercept associated with the corresponding condition]. These results suggest that altered albumin synthesis (or altered synthesis unable to compensate for albumin loss, catabolism or redistribution) is an important determinant of hypoalbuminemia after hepatectomy. The correlations with age and postoperative outcome support the concept that hypoalbuminemia is a marker of pathophysiologic frailty associated with increasing age, and amplified by the challenges of postoperative illness.

Differential expression of the fast skeletal muscle proteome following chronic low-frequency stimulation

Physiological and biochemical responses of skeletal muscle fibres to enhanced neuromuscular activity under conditions of maximum activation can be studied experimentally by chronic low-frequency stimulation of fast muscles. Stimulation-induced changes in the expression pattern of the rabbit fast skeletal muscle proteome were evaluated by two-dimensional gel electrophoresis and compared to the altered isoform expression profile of established transformation markers such as the Ca2+-ATPase, calsequestrin and the myosin heavy chain. Sixteen muscle proteins exhibited a marked change in their expression level. This included albumin with a 4-fold increase in abundance. In contrast, glycolytic enzymes, such as enolase and aldolase, showed a decreased expression. Concomitant changes were observed with marker elements of the contractile apparatus. While the fast isoforms of troponin T and myosin light chain 2 were drastically down-regulated, their slow counterparts exhibited increased expression. Interestingly, mitochondrial creatine kinase expression increased while the cytosolic isoform of this key muscle enzyme decreased. The expression of the small heat shock protein HSP-B5/alphaB-crystallin and the oxygen carrier protein myoglobin were both increased 2-fold following stimulation. The observed changes indicate that the conversion into fatigue-resistant red fibres depends on: (i) the optimum utilization of free fatty acids via albumin transportation, (ii) a rearrangement of the creatine kinase isozyme pattern for enhanced mitochondrial activity, (iii) an increased availability of oxygen for aerobic metabolism via myoglobin transport, (iv) the conversion of the contractile apparatus to isoforms with slower twitch characteristics and (v) the up-regulation of chaperone-like proteins for stabilising myofibrillar components during the fast-to-slow transition process.

Synthesis rates of total liver protein and albumin are both increased in patients with an acute inflammatory response

The general perception that catabolism and inflammation are associated with a high synthesis rate of total liver protein and a low albumin synthesis rate has been challenged in recent years by several studies in man, indicating that the synthesis rate of albumin in response to a catabolic insult is increased rather than decreased. Thus changes in liver protein synthesis rates in conjunction with catabolism and acute inflammation in man need to be characterized better. The aim of the present study was to measure protein synthesis rates of total liver protein and albumin during a state of acute inflammation. Patients (n = 10) undergoing acute laparoscopic cholecystectomy due to acute cholecystitis were investigated. FSRs (fractional synthesis rates) of total liver protein (liver biopsy specimens) and albumin (plasma samples) were investigated as early as possible during the surgical procedure, using a flooding dose of L-[2H5]phenylalanine. The results were compared with a reference group of patients without cholecystitis undergoing elective laparoscopic cholecystectomy (n = 17). FSR of total liver protein was 60% higher (P < 0.001) and the FSR of albumin was 45% higher (P < 0.01) in the cholecystitis patients compared with the control group. In conclusion, the synthesis rates of total liver protein and albumin are both increased in patients with an acute general inflammatory reaction undergoing laparoscopic cholecystectomy.

Assessing Nutritional Status in Chronically Critically Ill Adult Patients

• Background Numerous methods are used to measure and assess nutritional status of chronically critically ill patients.

• Objectives To discuss the multiple methods used to assess nutritional status in chronically critically ill patients, describe the nutritional status of chronically critically ill patients, and assess the relationship between nutritional indicators and outcomes of mechanical ventilation.

• Methods A descriptive, longitudinal design was used to collect weekly data on 360 adult patients who required more than 72 hours of mechanical ventilation and had a hospital stay of 7 days or more. Data on body mass index and biochemical markers of nutritional status were collected. Patients’ nutritional intake compared with physicians’ orders, dieticians’ recommendations, and indirect calorimetry and physicians’ orders compared with dieticians’ recommendations were used to assess nutritional status. Relationships between nutritional indicators and variables of mechanical ventilation were determined.

• ResultsInconsistencies among nurses’ implementation, physicians’ orders, and dieticians’ recommendations resulted in wide variations in patients’ calculated nutritional adequacy. Patients received a mean of 83% of the energy intake ordered by their physicians (SD 33%, range 0%–200%). Patients who required partial or total ventilator support upon discharge had a lower body mass index at admission than did patients with spontaneous respirations (Mann-Whitney U = 8441, P = .001).

• Conclusions In this sample, the variability in weaning progression and outcomes most likely reflects illness severity and complexity rather than nutritional status or nutritional therapies. Further studies are needed to determine the best methods to define nutritional adequacy and to evaluate nutritional status.

Oxidative stress and ageing: is ageing a cysteine deficiency syndrome?

Reactive oxygen species (ROS) are constantly produced in biological tissues and play a role in various signalling pathways. Abnormally high ROS concentrations cause oxidative stress associated with tissue damage and dysregulation of physiological signals. There is growing evidence that oxidative stress increases with age. It has also been shown that the life span of worms, flies and mice can be significantly increased by mutations which impede the insulin receptor signalling cascade. Molecular studies revealed that the insulin-independent basal activity of the insulin receptor is increased by ROS and downregulated by certain antioxidants. Complementary clinical studies confirmed that supplementation of the glutathione precursor cysteine decreases insulin responsiveness in the fasted state. In several clinical trials, cysteine supplementation improved skeletal muscle functions, decreased the body fat/lean body mass ratio, decreased plasma levels of the inflammatory cytokine tumour necrosis factor alpha (TNF-alpha), improved immune functions, and increased plasma albumin levels. As all these parameters degenerate with age, these findings suggest: (i) that loss of youth, health and quality of life may be partly explained by a deficit in cysteine and (ii) that the dietary consumption of cysteine is generally suboptimal and everybody is likely to have a cysteine deficiency sooner or later.

Hypoalbuminemia 3 months after hospital discharge: significance for long-term survival

OBJECTIVES

To determine change in albumin from hospital discharge to 3-month follow-up and the prognostic significance of persistent hypoalbuminemia in older veteran patients.

DESIGN

A prospective cohort study.

SETTING

A geriatric rehabilitation unit of a university-affiliated Department of Veterans Affairs hospital.

PARTICIPANTS

The study population consisted of 282 subjects (of 322 randomly selected discharges who were free of cancer and terminal conditions) that completed the 90-day postdischarge assessment; most were older (75.4+/-8.6), white (76%), and male (99%).

MEASUREMENTS

Each subject completed a comprehensive discharge assessment, had a repeat albumin an average of 94 days later, and was then tracked for 5 years. The strongest predictors of survival were identified using Cox proportional hazards regression analysis.

RESULTS

Between hospital discharge and the 3-month reassessment, albumins improved by more than 2 g/L in 122 subjects (43%), stayed the same in 112 subjects (40%), and deteriorated by more than 2 g/L in the rest. During follow-up, 190 subjects (67%) died. Of the 38 nutritional, functional, demographic, and illness severity variables evaluated, the 3-month postdischarge albumin was the strongest predictor of long-term mortality. Those with albumins less than 35 g/L had a 2.6 times greater mortality than those with albumins of 40 g/L or greater (relative risk=2.6, 95% confidence interval=1.8-3.8). After controlling for 3-month albumin, hospital-discharge albumin was not significantly associated with long-term mortality.

CONCLUSION

In older people, a low serum albumin 3 months after hospital discharge is associated with a poor long-term prognosis. It is not known whether this represents ongoing inflammation or inadequate nutrition.

Serum Albumin and Muscle Strength: A Longitudinal Study in Older Men and Women

OBJECTIVES

To examine whether low serum albumin is associated with low muscle strength and future decline in muscle strength in community-dwelling older men and women.

DESIGN

Population-based cohort study.

SETTING

The Longitudinal Aging Study Amsterdam.

PARTICIPANTS

Six hundred seventy-six women and 644 men aged 65 to 88.

MEASUREMENTS

Serum albumin was determined at baseline. Muscle strength was assessed using grip strength at baseline, after 3 (n=1,009), and 6 (n=741) years. The outcomes were continuous baseline muscle strength, 3- and 6-year change in muscle strength, and a dichotomous indicator for substantial decline (a decrease if > or =1 standard deviations for women=11 kg, for men=12 kg) in muscle strength.

RESULTS

Mean serum albumin concentration+/-standard deviation was 45.0+/-3.3 g/L for women and 45.2+/-3.2 g/L for men. At baseline, adjusting for age, lifestyle factors, and chronic conditions, lower serum albumin was cross-sectionally associated with weaker muscle strength (P<.001) in women and men. After 3 years of follow-up, mean decline in muscle strength was -5.6+/-10.9 kg in women and -9.6+/-11.9 kg in men. After adjustment for potential confounders, lower serum albumin was associated with muscle strength decline over 3 years (P<.01) in women and men (beta=0.57, standard error (SE)=0.18; beta=0.37, SE=0.16, respectively). Lower serum albumin was also associated with substantial decline in muscle strength in women (per unit albumin (g/L) adjusted odds ratio (OR)=1.14, one-sided 95% confidence limit (CL)=1.07) and men (per unit albumin (g/L) adjusted OR=1.14, 95% CL=1.08). Similar but slightly weaker associations were found between serum albumin and 6-year change in muscle strength (P<.05).

CONCLUSION

These results suggest that low serum albumin, even within the normal range, is independently associated with weaker muscle strength and future decline in muscle strength in older women and men.

Change in serum albumin and subsequent decline in functional status in older persons

BACKGROUND AND AIMS

This study examines whether a three-year change in serum albumin concentration is associated with subsequent decline in functional status in older persons.

METHODS

A total of 588 participants from the Longitudinal Aging Study Amsterdam aged 65-85 years were followed for six years. The three-year change in serum albumin was classified in four groups: chronic low (< or =43 g/L at both time points), decrease (decrease of 2.4% or more) from normal to low, decrease but still normal, and stable normal albumin (reference group). During the subsequent three years, absolute change and a decline of one standard deviation or more (termed substantial decline) in functional status was assessed. Functional status was measured in two ways: using performance tests and self-reported functional ability.

RESULTS

Substantial decline in functional performance and functional ability was observed in 243 persons (41.3%) and 133 persons (22.6%), respectively. After adjustment for baseline functional status and potential confounders, chronic low albumin and a decrease from normal to low albumin were associated with a greater absolute decline in functional performance and in self-reported functional ability. Using the outcome substantial decline in functional status, only decrease to low serum albumin was associated with decline in functional ability [odds ratio (OR)=1.97; one-sided 95% Confidence Limit (CL)=1.09].

CONCLUSIONS

This study indicates that chronic low serum albumin is a determinant of decline in functional status. However, a decrease in serum albumin from normal to low levels but within the normal range was a stronger determinant of future decline in functional status. Change in serum albumin level within the normal range measured between two points in time may be used as a general marker of future functional decline.

The albumin controversy

There are relatively few studies of albumin use in neonates and children, with most showing no consistent benefit compared with the use of crystalloid solutions. Certainly, albumin treatment is not indicated for treatment of hypoalbuminemia alone. Studies also show that albumin is not indicated in neonates for the initial treatment of hypotension, respiratory distress, or partial exchange transfusions. In adults, albumin is not considered to be the initial therapy for hypovolemia, burn injury, or nutritional supplementation. Based on the evidence, albumin should be used rarely in the neonatal ICU. Albumin may be indicated in the treatment of hypovolemia only after crystalloid infusion has failed. In patients with acute hemorrhagic shock, albumin may be used with crystalloids when blood products are not available immediately. Inpatients with acute or continuing losses of albumin and normal capillary permeability and lymphatic function, such as during persistent thoracostomy tube or surgical site drainage, albumin supplementation will prevent the development of hypoalbuminemia, and possibly edema formation. This has not been studied systematically, however. In patients with hypoalbuminemia and increased capillary permeability, albumin supplementation often leads to greater albumin leakage across the capillary membrane, contributing to edema formation without improvement in outcome. As the disease process improves and capillary permeability normalizes, albumin supplementation may accelerate recovery, but long-term benefits of albumin treatment usually cannot be demonstrated. These patients will recover whether or not albumin is administered.

Insulin treatment improves hepatic morphology and function through modulation of hepatic signals after severe trauma

OBJECTIVE

The purpose of the present study was to determine the effect of insulin therapy on hepatic function, structure, and hepatic mRNA and protein cytokine expression during the hypermetabolic cascade post burn.

SUMMARY BACKGROUND DATA

Liver function and morphology are crucial for survival of patients suffering from trauma, operations, or infections. Insulin decreased mortality and prevented the incidence of multiorgan failure in critically ill patients.

METHODS

Rats received a thermal injury and were randomly divided into the insulin or control group. Our outcome measures encompassed the effect of insulin on hepatic proteins, hepatic pro- and anti-inflammatory cytokines mRNA and proteins, hepatocyte proliferation, including Bcl-2 and hepatocyte apoptosis, with caspases-3 and caspases-9.

RESULTS

Insulin significantly improved hepatic protein synthesis by increasing albumin and decreasing c-reactive protein and fat (P < 0.05). Insulin decreased the hepatic inflammatory response signal cascade by decreasing hepatic pro-inflammatory cytokines mRNA and proteins IL-1beta and tumor necrosis factor at pretranslational levels. Insulin increased hepatic cytokine mRNA and protein expression of IL-2 and IL-10 at a pretranslational level when compared with controls (P < 0.05). Insulin increased hepatocyte proliferation along with Bcl-2 concentration, while decreasing hepatocyte apoptosis along with decreased caspases-3 and -9 concentration, thus improving liver morphology (P < 0.05).

CONCLUSIONS

Our data provide insight that insulin attenuates the inflammatory response by decreasing the pro-inflammatory and increasing the anti-inflammatory cascade, thus restoring hepatic homeostasis, which has been shown to be critical for organ function and survival of critically ill patients.

Liposome-mediated transfer of vascular endothelial growth factor cDNA augments survival of random-pattern skin flaps in the rat

Tissue engineering is an application for gene therapy that is in its infancy. We show that simple liposomal-mediated gene transfer could result in a potentially useful biological effect in the field of wound healing. cDNA encoding the 165 amino acid form of vascular endothelial growth factor complexed to commercially available liposomes was injected into rat skin 1 week before raising a random pattern 3 x 10 cm flap. The flap survival was enhanced by 14 percent, and was accomplished without accessing the arterial inflow of the territory. These results were statistically significant (p<0.002) and reproducible. No adverse effects were seen. Histological analysis of the angiogenesis localized much of the new vessel formation to the area around the hair follicles. Polymerase chain reaction amplification of extracted flap tissue confirmed the presence of the transgene.

Plasma citrulline: A marker of enterocyte mass in villous atrophy-associated small bowel disease

BACKGROUND & AIMS

Plasma citrulline, a nonprotein amino acid produced by enterocytes, was suggested as a marker of remnant enterocyte mass in patients with short bowel. Our objective was to evaluate citrulline as a marker of severity and extent of villous atrophy in patients without intestinal resection.

METHODS

Forty-two patients with celiac disease and 10 patients with non-celiac villous atrophy disease were studied by plasma postabsorptive citrulline and biological dosages, biopsies of proximal (duodenojejunal) small bowel and distal ileum (n = 25), or measurement of vitamin B(12) absorption (n = 4). Nine patients were reevaluated after following a gluten-free diet for 1 year. Controls were 51 healthy subjects and 10 severely malnourished patients with anorexia nervosa with no intestinal mucosal abnormalities.

RESULTS

Plasma citrulline concentration was lower (P < 0.001) in patients with villous atrophy (24 +/- 13 micromol/L) than in healthy subjects (40 +/- 10 micromol/L) and patients with anorexia nervosa (39 +/- 9 micromol/L). Three thresholds were individualized: <10 micromol/L for patients with diffuse total villous atrophy (n = 10), 10-20 micromol/L for patients with proximal-only total villous atrophy (n = 12), and 20-30 micromol/L for patients with partial villous atrophy (n = 10). Plasma citrulline concentration was correlated to the severity and extent of villous atrophy (r = 0.81; P < 0.001) and to albuminemia (r = 0.47; P < 0.01). Receiver operating characteristic curves indicated that plasma citrulline concentration was the best biological variable to predict villous atrophy. Following a 1-year gluten-free diet, plasma citrulline concentration increased in histologically responsive (n = 6) but not in unresponsive (n = 3) patients.

CONCLUSIONS

In patient villous atrophy diseases, plasma citrulline concentration may prove to be a simple and reliable marker of reduced enterocyte mass.

Increased albumin plasma efflux contributes to hypoalbuminemia only during early phase of sepsis in rats

The mechanisms leading to hypoalbuminemia in sepsis were explored by measuring plasma volume, albumin distribution, plasma albumin transcapillary escape rate (TER), and efflux (TER x albumin intravascular pool). These parameters were quantified in infected rats, injected intravenously with live Escherichia coli, and pair-fed and well-fed rats using an injection of (35)S-albumin and measuring plasma and whole body albumin concentrations. Animals were studied on days 1, 6, and 10 after infection. In pair-fed rats, neither albumin distribution nor exchange rate between the intra- and extravascular compartments was modified. The increase of plasma volume after infection partly explained hypoalbuminemia. Infection resulted in a reduction of the total albumin pool of the body all along the experimental period, indicating a net loss of the protein. Albumin TER (%/day) was significantly increased 1 and 6 days after infection, but the absolute efflux was increased only on day 1. Normal values were observed on day 10. Therefore, an accelerated plasma efflux contributes to hypoalbuminemia only during the early period of sepsis. During this phase, the protein was retained in the extravascular space where it was probably catabolized. Later on, other factors are probably involved.

Human albumin synthesis is increased by an ultra-endurance trial

PURPOSE

The purpose of this study was to determine whether an ultra-endurance event is a strong stimulus to increase albumin synthesis involved in the process of intravascular albumin mass increase associated with transient hypervolemia.

METHODS

The albumin synthetic rate was measured in six young men, 3 d before (C) and on the 1st (R1) and 8th (R8) days of the recovery from an ultra-endurance trial (5 h daily for 4 d). Albumin fractional (FSR) and absolute (ASR) synthetic rate were determined using a primed-constant infusion of [1(-13) C] leucine. Plasma volume (PV) using Evans Blue dye dilution and total body water (TBW) using bioelectrical impedance analysis were measured on C, R1, and R8.

RESULTS

On R1 as compared with C: 1). PV (+23.3 +/- 3.2%; P<or= 0.001) and TBW (+4.2 +/- 0.8%; P<or= 0.01) expanded; 2). FSR and ASR both increased from 5.36 +/- 0.46 to 6.86 +/- 0.62%.24 h (+ 29.0 +/- 7.1%; P<or= 0.01) and from 103 +/- 10 to 153 +/- 19 mg.kg body weight (-1).24 h (-1) (+47.5 +/- 6.8%; P<or= 0.01); and 3). plasma albumin and protein masses increased (P<or= 0.05) from 1.92 +/- 0.08 to 2.22 +/- 0.14 g.kg body weight (-1) (i.e., +15.3 +/- 4.9%) and from 3.15 +/- 0.18 to 3.56 +/- 0.21 g.kg body weight (-1) (+13.3 +/- 3.9%), respectively. By R8, all these parameters had returned to their control levels except for albumin mass (1.73 +/- 0.08 g.kg body weight(-1), which was lower than C ( P<or= 0.05).

CONCLUSION

The increase in the albumin synthetic rate the day after an ultra-endurance trial is a major event associated with a greater circulating protein mass. The impact of exercise on albumin synthesis has disappeared 8 d later, as did PV and total protein mass expansion.