Human serum albumin homeostasis: a new look at the roles of synthesis, catabolism, renal and gastrointestinal excretion, and the clinical value of serum albumin measurements

Clinical value of serum cholinesterase levels in Nephrotic syndrome: an observational study

Background

Nephrotic syndrome (NS) results in massive proteinuria and hypoalbuminemia, which are responsible for a compensatory increase in protein synthesis in the liver. Serum cholinesterase (ChE) also increases in NS. However, its clinical value is not fully elucidated.

Methods

In this study, 184 patients with NS who underwent kidney biopsy were included. The patients were divided into two groups according to serum ChE levels, as follows: hypercholinesterasemia (HC) and non-hypercholinesterasemia (NHC) groups. The clinical factors were compared between the two groups.

Results

The HC group had significantly more severe proteinuria and higher prevalence of high selective proteinuria than the NHC group. Furthermore, the prevalence of minimal change nephrotic syndrome (MCNS) was significantly higher in the HC group than that in the NHC group. Multivariate analysis revealed that the severity of proteinuria and MCNS were significantly associated with HC.

Conclusion

In this study, HC in NS was associated with the severity of proteinuria and MCNS, and could help clinicians predict the histological diagnosis of NS.

Absorption, distribution, metabolism, and excretion of methylene diphenyl diisocyanate and toluene diisocyanate: Many similarities and few differences

Methylene diphenyl diisocyanate (MDI) and toluene diisocyanate (TDI) are high production volume chemicals used for the manufacture of polyurethanes. For both substances, the most relevant adverse health effects after overexposure in the workplace are isocyanate-induced asthma, lung function decrement and, to a much lesser extent, skin effects. Over the last two decades many articles have addressed the reactivity of MDI and TDI in biological media and the associated biochemistry, which increased the understanding of their biochemical and physiological behavior. In this review, these new insights with respect to similarities and differences concerning the adsorption, distribution, metabolism, and excretion (ADME) of these two diisocyanates and the implications on their toxicities are summarized. Both TDI and MDI show very similar behavior in reactivity to biological macromolecules, distribution, metabolism, and excretion. Evidence suggests that the isocyanate (NCO) group is scavenged at the portal-of-entry and is not systemically available in unbound reactive form. This explains the lack of other than portal-of-entry toxicity observed in repeated-dose inhalation tests.

Retinoids as anti-cancer agents and their mechanisms of action

Retinoids (vitamin A) have been reported extensively for anti-cancer properties due to their high receptor-binding affinities and gene regulation abilities. However, the anti-cancer potential of retinoids has not been reviewed in recent years. Thus, this review focused on the anti-cancer effects of retinoids and their synergistic effects with other drugs, together with their mechanisms of action in different types of cancers reported in the past five years. The retinoids were well studied in breast cancer, melanoma, and colorectal cancer. Synthetic retinoids have shown higher selectivity, stronger effectiveness, and lower toxicity than endogenous retinoids. Interestingly, the combination treatment of endogenous retinoids with chemotherapy drugs showed enhanced anti-cancer effects. The mechanisms of action reported for retinoids mainly involved the RAR/RXR signaling pathway. However, limited clinical studies were conducted in recent years. Thus, retinoids which are highly potential anti-cancer agents are worth further study in clinical, especially as a combination therapy with chemotherapy drugs.

Universal Accessible Biomarkers of Drug-Induced Tissue Injury and Systemic Inflammation in Rat: Performance Assessment of TIMP-1, A2M, AGP, NGAL and Albumin

The ability to monitor for general drug-induced tissue injury (DITI) or systemic inflammation in any tissue using blood-based accessible biomarkers would provide a valuable tool in early exploratory animal studies to understand potential drug liabilities. Here we describe the evaluation of four biomarkers of tissue remodeling and inflammation [α2-macroglobin (A2M), α1-acid glycoprotein (AGP), neutrophil gelatinase-associated lipocalin (NGAL) and tissue inhibitor of metalloproteinases (TIMP-1)] as well as the traditional serum parameter albumin as potential blood-based biomarkers of DITI and systemic inflammatory response (SIR). Biomarker performance was assessed in 51 short-term rat in vivo studies with various end-organ toxicities or SIR and receiver operator characteristic (ROC) curves were generated to compare relative performances. All four biomarkers performed well in their ability to detect DITI and SIR with an area under the curve (AUC) of 0.82 - 0.78, however TIMP-1 achieved the best sensitivity (at 95% specificity) of 61%; AGP, NGAL, and A2M sensitivity was 51-52%. AUC for albumin was 0.72 with sensitivity of 39%. A2M was the best performer in studies with only SIR (AUC 0.91). In the subset of studies with drug-induced vascular injury, TIMP-1 performed best with an AUC of 0.96. Poor performance of all tested biomarkers was observed in samples with CNS toxicity. In summary, TIMP-1, A2M, AGP and NGAL demonstrated performance as sensitive accessible biomarkers of DITI and SIR, supporting their potential application as universal accessible tissue toxicity biomarkers to quickly identify dose levels associated with drug-induced injury in early exploratory rat safety and other studies.

Engineering interferons and interleukins for cancer immunotherapy

Cytokines are a class of potent immunoregulatory proteins that are secreted in response to various stimuli and act locally to regulate many aspects of human physiology and disease. Cytokines play important roles in cancer initiation, progression, and elimination, and thus, there is a long clinical history associated with the use of recombinant cytokines to treat cancer. However, the use of cytokines as therapeutics has been limited by cytokine pleiotropy, complex biology, poor drug-like properties, and severe dose-limiting toxicities. Nevertheless, cytokines are crucial mediators of innate and adaptive antitumor immunity and have the potential to enhance immunotherapeutic approaches to treat cancer. Development of immune checkpoint inhibitors and combination immunotherapies has reinvigorated interest in cytokines as therapeutics, and a variety of engineering approaches are emerging to improve the safety and effectiveness of cytokine immunotherapy. In this review we highlight recent advances in cytokine biology and engineering for cancer immunotherapy.

Assessing the Validity of Normalizing Aflatoxin B1-Lysine Albumin Adduct Biomarker Measurements to Total Serum Albumin Concentration across Multiple Human Population Studies

The assessment of aflatoxin B₁ (AFB₁) exposure using isotope-dilution liquid chromatography-mass spectrometry (LCMS) of AFB₁-lysine adducts in human serum albumin (HSA) has proven to be a highly productive strategy for the biomonitoring of AFB₁ exposure. To compare samples across different individuals and settings, the conventional practice has involved the normalization of raw AFB₁-lysine adduct concentrations (e.g., pg/mL serum or plasma) to the total circulating HSA concentration (e.g., pg/mg HSA). It is hypothesized that this practice corrects for technical error, between-person variance in HSA synthesis or AFB₁ metabolism, and other factors. However, the validity of this hypothesis has been largely unexamined by empirical analysis. The objective of this work was to test the concept that HSA normalization of AFB₁-lysine adduct concentrations effectively adjusts for biological and technical variance and improves AFB₁ internal dose estimates. Using data from AFB₁-lysine and HSA measurements in 763 subjects, in combination with regression and Monte Carlo simulation techniques, we found that HSA accounts for essentially none of the between-person variance in HSA-normalized (R² = 0.04) or raw AFB₁-lysine measurements (R² = 0.0001), and that HSA normalization of AFB₁-lysine levels with empirical HSA values does not reduce measurement error any better than does the use of simulated data (n = 20,000). These findings were robust across diverse populations (Guatemala, China, Chile), AFB₁ exposures (10⁵ range), HSA assays (dye-binding and immunoassay), and disease states (healthy, gallstones, and gallbladder cancer). HSA normalization results in arithmetic transformation with the addition of technical error from the measurement of HSA. Combined with the added analysis time, cost, and sample consumption, these results suggest that it may be prudent to abandon the practice of normalizing adducts to HSA concentration when measuring any HSA adducts—not only AFB₁-lys adducts—when using LCMS in serum/plasma.

Dual detection high-speed capillary electrophoresis for simultaneous serum protein analysis and immunoassays

Serum protein electrophoresis (SPE) separates serum proteins into bands whose shape and amplitude can alert clinicians to a range of disorders. This is followed by more specific immunoassays to quantify important antigens and confirm a diagnosis. Here we develop a high-speed capillary electrophoresis (HSCE) platform capable of simultaneous SPE and immunoassay measurements. A single laser excitation source is focused into the detection zone of the capillary to measure both refractive index (SPE) and fluorescence signals (immunoassays). The refractive index signal measures characteristic SPE profiles for human serum separated in 100 mM boric acid (pH 10), 100 mM arginine (pH 11), and 20 mM CHES (pH 10). For the immunoassay, the fluorescence electropherograms reveal that CHES provides the optimal buffer for measuring the immunocomplex and separating it from the free antigen. Immunoassays in CHES yield a LOD of 23 nM and a LOQ of 70 nM for the detection of fluorescein. The high pH reduces protein adsorption but reduces antibody affinity. Preliminary studies carried out in 50 mM barbital at pH 8 show improved stability of the immunocomplex and better separation for immunoassay quantification. Further optimization will open new capabilities for measuring orthogonal diagnostic signals in seconds with HSCE.

Longitudinal Assessment of Prenatal, Perinatal, and Early-Life Aflatoxin B1 Exposure in 828 Mother-Child Dyads from Bangladesh and Malawi

BACKGROUND

In utero or early-life exposure to aflatoxin, which contaminates staple crops in disadvantaged settings, may compromise pregnancy and infant outcomes, but investigations into the extent, persistence, and determinants of aflatoxin exposure at these life stages have lacked longitudinal data collection and broad geographic representation.

OBJECTIVES

Aflatoxin exposure and selected determinants thereof were characterized in mother-child dyads with serial plasma/serum samples in prenatal, perinatal, and early life in Malawi and Bangladesh.

METHODS

Circulating aflatoxin B1 (AFB1)-lysine albumin adducts were measured in dyads from Bangladesh (n = 573; maternal first and third trimester, 3 mo postpartum, cord blood, infant 24 mo) and Malawi (n = 255; maternal second and third trimester, 6 mo postpartum, infant 6 and 18 mo) with isotope dilution mass spectrometry. We examined AFB1-lysine adduct magnitude, persistence, seasonality, and associations with infant feeding, and estimated daily AFB1 intake.

RESULTS

Maternal AFB1-lysine was higher in Malawi (98% detectable; median: 0.469, IQR: 0.225-1.027 pg/µL) than in Bangladesh (59%; 0.030, nondetectable [nd]-0.077 pg/µL). Although estimated dietary exposure in Malawi was temporally stable (648 ng AFB1/day), estimated intake in Bangladesh was reduced by 94% between rainy and winter seasons (98 to 6 ng/day). AFB1-lysine was low in cord blood from Bangladesh (15% detectable; 0.045, 0.031-0.088 pg/µL among detectable) and in Malawian infants at 6 mo of age (0.072, nd-0.236 pg/µL), but reached maternal concentrations by 18 or 24 mo (Bangladesh: 0.034, nd-0.063 pg/µL; Malawi: 0.370, 0.195-0.964 pg/µL). In Malawian infants, exclusive breastfeeding at 3 mo was associated with 58% lower AFB1-lysine concentrations at 6 mo compared with other feeding modes (P = 0.010).

CONCLUSIONS

Among pregnant women, aflatoxin exposure was persistently high in Malawi, while lower and seasonal in Bangladesh. Infants were partially protected from exposure in utero and with exclusive breastfeeding, but exposures reached adult levels by 18-24 mo of age. The Bangladesh and Malawi trials are registered at clinicaltrials.gov as NCT00860470 and NCT01239693.

Effects of Perioperative Oral Nutrition Supplementation in Malaysian Patients Undergoing Elective Surgery for Breast and Colorectal Cancers-A Randomised Controlled Trial

This study aimed to investigate the effectiveness of preoperative and an extended 90-days postoperative use of ONS among patients undergoing elective surgery for breast and colorectal cancers. Ninety-one patients were randomised into (i) Group SS received ONS up to 14 days preoperatively and postoperatively up to discharge, (ii) Group SS-E received ONS up to 14 days preoperatively, postoperatively up to discharge and for an extended 90-days after discharge and (iii) Group DS received ONS postoperatively up to discharge. Preoperatively, SS had significantly higher body weight (66.1 ± 15.3 kg vs. 62.5 ± 12.0 kg, p = 0.010) and BMI (26.8 ± 6.8 kg/m2 vs. 26.1 ± 6.7 kg/m2, p = 0.022) than DS when adjusted for baseline values. Postoperatively, SS-E had significantly higher handgrip strength (26 ± 9 kgF vs. 24 ± 6 kgF, p = 0.044) than DS at 90-days post-discharge after adjusted for preoperative values. At 90-days post-discharge, the proportions of patients in SS with albumin < 35 g/d, CAR ≥ 0.1, mPINI ≥ 0.4, mGPS score 1 or 2 were significantly reduced while in SS-E, the reduction in proportions of patients with high hsCRP and mPINI ≥ 0.4 was significant compared to upon discharge. Preoperative ONS had modest benefits in attenuating weight loss whilst postoperative supplementation up to 90-days post-discharge improved handgrip strength and inflammatory prognostic markers.

Preparation of fatty acid solutions exerts significant impact on experimental outcomes in cell culture models of lipotoxicity

Free fatty acids are essentially involved in the pathogenesis of chronic diseases such as diabetes mellitus, non-alcoholic fatty liver disease, and cardiovascular disease. They promote mitochondrial dysfunction, oxidative stress, respiratory chain uncoupling, and endoplasmic reticulum stress and modulate stress-sensitive pathways. These detrimental biological effects summarized as lipotoxicity mainly depend on fatty acid carbon chain length, degree of unsaturation, concentration, and treatment time. Preparation of fatty acid solutions involves dissolving and complexing. Solvent toxicity and concentration, amount of bovine serum albumin (BSA), and ratio of albumin to fatty acids can vary significantly between equal concentrations, mediating considerable harmful effects and/or interference with certain assays such as 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT). Herein, we studied the impact of commonly used solvents ethanol and dimethyl sulfoxide and varying concentrations of BSA directly and in solution with oleic acid on MTT to formazan conversion, adenosine triphosphate level, and insulin content and secretion of murine β-cell line MIN6 employing different treatment duration. Our data show that experimental outcomes and assay readouts can be significantly affected by mere preparation of fatty acid solutions and should thus be carefully considered and described in detail to ensure comparability and distinct evaluation of data.

Assessment of Cystatin-C level in Newly Diagnosed Iraqi Children with Nephritic Syndrome

BACKGROUND: Nephritic syndrome (NS) is a common kidney disease in children that causes protein leakage from the blood into the urine due to glomerular injury. AIM: The aim of this research was to determine the level of Cystatin-C (CysC) and other biochemical parameters in newly diagnosed NS children in Iraq. PATIENTS AND METHODS: Ninety Iraqi children divided into: 50 children with newly diagnosed NS (28 boys and 22 girls) aged between (4 and 16) years, and 40 healthy control children (20 boys and 20 girls) aged between (5 and 16) years, who were attending Al-Yarmouk Teaching Hospital, Baghdad. RESULTS: There was a significant increase in blood urea, serum total cholesterol (S.TC), and serum low density lipoprotein (S.LDL) and a significant decreased of serum creatinine (S. creatinine), protein/creatinine ratio, serum total bilirubin, serum albumin, and serum high density lipoprotein, while a highly significant increased (p < 0.001) of CysC levels in children with newly diagnosed NS when compared with control group. A significant positive correlation between CysC level versus systolic blood pressure, body mass index, diastolic blood pressure, S.TC, S. LDL cholesterol (S.LDL-C), S. Total Bilirubin, S. Albumin, S. Total protein, and B. urea, while a significant negative correlation was found between CysC level versus serum low density lipoprotein cholesterol and estimated glomerular filtration rate in children with newly diagnosed NS. CONCLUSION: It may come to the conclusion that CysC can be the best predictor of overall efficacy than creatinine and in the diagnosis of any damage to the kidney in children with NS.

Exploiting cancer's drinking problem: regulation and therapeutic potential of macropinocytosis

Macropinocytosis, an evolutionarily conserved endocytic mechanism that mediates non-specific fluid-phase uptake, is potently upregulated by various oncogenic pathways. It is now well appreciated that high macropinocytic activity is a hallmark of many human tumors, which use this adaptation to scavenge extracellular nutrients for fueling cell growth. In the context of the nutrient-scarce tumor microenvironment, this process provides tumor cells with metabolic flexibility. However, dependence on this scavenging mechanism also illuminates a potential metabolic vulnerability. As such, there is a great deal of interest in understanding the molecular underpinnings of macropinocytosis. In this review, we will discuss the most recent advances in characterizing macropinocytosis: the pathways that regulate it, its contribution to the metabolic fitness of cancer cells, and its therapeutic potential.

Gestational Age-Dependent Reference Ranges for Albumin Levels in Cord Serum

BACKGROUND

To diagnose hypoalbuminemia in newborns, it is essential to establish a definition applicable to those with a different gestational age (GA) and clinical conditions. A positive correlation between serum albumin levels and GA has been reported, but the study was limited to small numbers of newborns. We therefore investigated the GA-dependent reference ranges for serum albumin levels using cord venous blood (UC-Alb levels) from a large number of newborns delivered at a tertiary perinatal center.

METHODS

Albumin levels were assessed in 2,917 newborns at 22-41 weeks of GA after exclusion of those with congenital disorders. Linear regression analysis was used to correlate GA and UC-Alb levels. After calculation of the percentile values of UC-Alb levels for each week of GA, the distributions were approximated by the least-squares method. To validate the determined linear approximation of the 5%ile value, the UC-Alb levels in newborns with hydrops fetalis and gastroschisis were used.

RESULTS

A significant positive correlation between GA and UC-Alb levels was found (rs = 0.701, p < 0.001, respectively). The distribution of the 5%ile of UC-Alb levels (Y) by GA (X) was approximated as a straight line (Y = 0.062 × X + 0.326, R2 = 0.951). Among the 59 and 18 newborns with hydrops fetalis and gastroschisis, 51 (86.4%) and 15 (83.3%), respectively, were below the line.

CONCLUSIONS

We established GA-dependent reference ranges for serum albumin levels, which may be useful to accurately diagnose hypoalbuminemia in newborns.

Albumin level and progression of coronary artery lesions in Kawasaki disease: A retrospective cohort study

BACKGROUND

Albumin (ALB) level is closely associated with the occurrence of intravenous immunoglobulin (IVIG) resistance and coronary artery lesions (CALs) in Kawasaki disease (KD). The association between ALB level and CALs progression, is critical to the prognosis of KD patients. But little is known about it. This study aims to investigate the effect of the ALB level on CALs progression in KD patients.

METHODS

A total of 3,479 KD patients from 1 January 2005 to 30 November 2020, in Wenzhou, China were recruited. A total of 319 KD patients who had CALs and ALB data, and finish the follow-up as requested were enrolled in this study. They were classified into the low ALB group and the normal ALB group, divided by 30 g/L. CALs outcomes were classified into two categories according to the CALs changes from the time that CALs were detected within 48 h before or after IVIG treatment to 1 month after disease onset: progressed and no progressed. Multiple logistic regression models were used to assess the independent effect of ALB level on CALs progression among KD patients. Stratified analysis was performed to verify the ALB level on CALs progression among patients in different subgroups.

RESULTS

Higher proportion of IVIG resistance (P < 0.001), receiving non-standard therapy (P < 0.001), and receiving delayed IVIG treatment (P = 0.020) were detected in patients with lower ALB level. Patients with lower ALB level had higher C-reactive protein (CRP) level (P = 0.097) and white blood cell count (WBC) (P = 0.036). After adjustment for confounders, patients with lower ALB level had higher odds of CALs progression; the adjusted odds ratio (OR) was 3.89 (95% CI: 1.68, 9.02). Similar results were found using stratification analysis and sensitivity analysis. Male gender and age over 36 months, as covariates in multiple logistic regression models, were also associated with CALs progression.

CONCLUSION

Low ALB level is identified as an independent risk factor for CALs progression in KD patients. Male gender and age over 36 months are also proved to be risk factors for CALs progression. Further investments are required to explore its mechanisms.

Predictive Value of C-Reactive Protein and Albumin for Temporal Within-Individual Pharmacokinetic Variability of Voriconazole in Pediatric Hematopoietic Cell Transplant Patients

Voriconazole is a widely used antifungal agent in immunocompromised patients, but its utility is limited by its variable exposure and narrow therapeutic index. Population pharmacokinetic (PK) models have been used to characterize voriconazole PK and derive individualized dosing regimens. However, determinants of temporal within-patient variability of voriconazole PK were not well-established. We aimed to characterize temporal variability of voriconazole PK within individuals and identify predictive clinical factors. This study was conducted as a part of a single-institution, phase I study of intravenous voriconazole in children undergoing HCT (NCT02227797). We analyzed voriconazole PK study data collected at week 1 and again at week 2 after the start of voriconazole therapy in 59 pediatric HCT patients (age <21 years). Population PK analysis using nonlinear mixed effect modeling was performed to analyze temporal within-individual variability of voriconazole PK by incorporating a between-occasion variability term in the model. A two-compartment linear elimination model incorporating body weight and CYP2C19 phenotype described the data. Ratio of individual voriconazole clearance between weeks 1 to 2 ranged from 0.11 to 3.3 (-9.1 to +3.3-fold change). Incorporation of covariate effects by serum C-reactive protein (CRP) and albumin levels decreased between-occasion variability of clearance (coefficient of variation: from 59.5% to 41.2%) and improved the model fit (p<0.05). As significant covariates on voriconazole PK, CRP and albumin concentrations may potentially serve as useful biomarkers as part of therapeutic drug monitoring. This article is protected by copyright. All rights reserved.

Association Between Serum Albumin and Hospital-Acquired Infections After Aneurysmal Subarachnoid Hemorrhage

BACKGROUND

Low serum albumin levels have been identified as a predictor of infectious complications in critically ill patients. However, the association in patients with aneurysmal subarachnoid hemorrhage (aSAH) remains unclear. We aimed to evaluate the prognostic value of hypoalbuminemia using blood samples at admission in patients with aSAH.

METHODS

In a multicenter observational study of patients with aSAH, serum albumin counts were collected on admission. Hypoalbuminemia was defined as a total albumin level < 35 g/L. Multivariable logistic regression analyses and propensity score matching were performed to obtain the adjusted odds ratios (ORs) with 95% confidence intervals (CI) for the primary outcome of hospital-acquired infections.

RESULTS

A total of 5448 patients were included in the observational cohort study. The odds of hospital-acquired infections were significantly higher in patients with albumin levels 30-34.9 g/L (OR 1.62, 95% CI 1.38-1.90), 25-29.9 g/L (OR 1.97, 95% CI 1.54-2.51), and < 24.9 g/L (OR 2.43, 95% CI 1.53-3.86) compared with patients with albumin level ≥ 35 g/L. The odds of hospital-acquired infections with a change in albumin levels from admission to 48-72 h later of lower than - 10 g/L and - 10 to - 5 g/L were 1.67 (95% CI 1.41-1.86) and 1.24 (95% CI 1.05-1.46), respectively, compared with a change in albumin levels of - 5 to 5 g/L.

CONCLUSIONS

In this large study of matched patients with aSAH, hypoalbuminemia at admission was associated with hospital-acquired infections. A decrease in serum albumin levels within 72 h of admission was associated with higher hospital-acquired infections.

Independent and joint effects of high-sensitivity c-reactive protein and hypoalbuminemia on long-term all-cause mortality among coronary artery disease: a prospective and multicenter cohort study

Background

High-sensitivity C-reactive protein (hs-CRP) plays an important role in hypoalbuminemia as a representative of inflammation, which is closely associated with poor prognosis among patients with coronary artery disease (CAD). The present study aimed to evaluate the independent and joint effects of high hs-CRP levels and hypoalbuminemia on long-term mortality among CAD patients.

Methods

A total of 1449 CAD patients were included from a prospective, multicenter, observational cohort study (REICIN, NCT01402232) of patients referred for coronary angiography (CAG). The primary endpoint was long-term all-cause death.

Results

During a median follow-up of 2.9 (2.0–3.0) years, a total of 107 (7.4%) patients died. The long-term mortality was higher among CAD patients with high hs-CRP levels (> 3 mg/L) than those with the low hs-CRP levels (≤ 3 mg/L; 10.7% versus 4.1%; hazard ratio [HR] 2.49; 95% confidence interval [CI] 1.48–4.17). Similarly, CAD patients with hypoalbuminemia had higher mortality than those without hypoalbuminemia (12.2% versus 4.9%; HR 1.93; 95% CI 1.20–3.08). When hs-CRP and albumin were combined, CAD patients with high hs-CRP levels (> 3 mg/L) and with hypoalbuminemia were at the highest risk of death compared with their reference group (hs-CRP ≤ 3 mg/L and albumin > 35 g/L; HR 3.79; 95% CI 1.91–7.52).

Conclusions

High hs-CRP levels and hypoalbuminemia were independently and jointly associated with long-term mortality among CAD patients. Patients with high hs-CRP levels and hypoalbuminemia had the highest risk of long-term mortality compared with other groups.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12872-021-02431-6.

Hypoalbuminemia affects one third of acute pancreatitis patients and is independently associated with severity and mortality

The incidence and medical costs of acute pancreatitis (AP) are on the rise, and severe cases still have a 30% mortality rate. We aimed to evaluate hypoalbuminemia as a risk factor and the prognostic value of human serum albumin in AP. Data from 2461 patients were extracted from the international, prospective, multicentre AP registry operated by the Hungarian Pancreatic Study Group. Data from patients with albumin measurement in the first 48 h (n = 1149) and anytime during hospitalization (n = 1272) were analysed. Multivariate binary logistic regression and Receiver Operator Characteristic curve analysis were used. The prevalence of hypoalbuminemia (< 35 g/L) was 19% on admission and 35.7% during hospitalization. Hypoalbuminemia dose-dependently increased the risk of severity, mortality, local complications and organ failure and is associated with longer hospital stay. The predictive value of hypoalbuminemia on admission was poor for severity and mortality. Severe hypoalbuminemia (< 25 g/L) represented an independent risk factor for severity (OR 48.761; CI 25.276-98.908) and mortality (OR 16.83; CI 8.32-35.13). Albumin loss during AP was strongly associated with severity (p < 0.001) and mortality (p = 0.002). Hypoalbuminemia represents an independent risk factor for severity and mortality in AP, and it shows a dose-dependent relationship with local complications, organ failure and length of stay.

Review: Roles of human serum albumin in prediction, diagnoses and treatment of COVID-19

The severe acute respiratory syndrome corona virus-2 (SARS-CoV-2) keeps on destroying normal social integrity worldwide, bringing about extraordinary medical services, cultural and financial interruption. Individuals with diabetes have been demonstrated to be at higher risk of complications and even death when exposed to SARS-CoV-2. Regardless of pandemic scale infection, there is presently limited comprehension on the potential impact of SARS-CoV-2 on individuals with diabetes. Human serum albumin (HSA) is the most abundant circulating plasma protein in human serum and attracted more interest from researchers because most susceptible to non-enzymatic glycation reactions. Albumin down-regulates the expression of ACE2 that is the target receptor of COVID-19. Hypoalbuminemia, coagulopathy, and vascular disease have been connected in COVID-19 and appear to predict outcomes independent of age and morbidity. This review discusses the most recent evidence that the ACE/ACE2 ratio could influence by human serum albumin both the susceptibility of individuals to SARS-CoV-2 infection and the outcome of the COVID-19 disease.

The association between low protein diet and body composition, muscle function, inflammation, and amino acid-based metabolic profile in chronic kidney disease stage 3-5 patients

BACKGROUND

Chronic kidney disease (CKD) is a global burden in the world. Low protein diet (LPD) recommendation is suggested in CKD patients to avoid or defer dialysis initiation and slow down CKD progression. However, nutritional imbalance and protein energy wasting represent key worries. The amino acid-based metabolic profile may provide a sensitive biomarker to evaluate CKD patients' nutrition status with LPD recommendations.

METHODS

We conducted a cross-sectional study in CKD stage 3-5 patients who had received LPD recommendation to evaluate the association between LPD and traditional markers (including plasma levels of albumin, pre-albumin, transferrin, total iron-binding capacity), inflammation markers (including peripheral leukocyte count and plasma levels of high-sensitivity C-reactive protein), body composition, muscle strength, and physical function, and novel nutrition markers (including amino acid-based metabolic profile) in CKD stage 3-5 patients.

RESULTS

In our study CKD stage 3-5 patients with the total number of 73, the mean age was around 71 ± 10 years old. The mean daily protein intake (DPI) was around 0.9 ± 0.3 g/kg/day and 25 (34%) patients met the recommended goal of DPI <0.8 g/kg/day. The mean daily calorie intake (DCI) was around 23 ± 6 kcal/kg/day, with only 11 (15%) patients met the recommend DCI with 30-35 kcal/kg/day. Compared to CKD patients with non-LPD, patients with LPD had significantly lower hemoglobin and albumin levels, shorter 6-min walking distance (6MWD), and lower leucine levels. Multivariable analysis found that lower hemoglobin and leucine levels, and shorter 6MWD were negatively and independently associated with LPD (all p < 0.05). Then ROC curve analysis found that the optimal cut-off value of leucine plasma levels was 95.5 μM with 60% sensitivity and 71% specificity to predict those CKD patients with LPD with the area under the curve of 0.646 (95% CI: 0.512-0.780).

CONCLUSION

LPD attainment was noted in 34% patients and most of CKD stage 3-5 patients (around 85%) had inadequate daily calorie intake although receiving standard dietary counseling routinely. A low protein diet and inadequate daily calorie intake in CKD patients were associated with shorter 6MWD, and lower hemoglobin and leucine levels. Plasma leucine levels lower than 95.5 μM may be a herald for muscle wasting and malnutrition in these CKD stage 3-5 patients with inadequate calorie intake.

In vivo Toxicity Assessment of Refined Red Palm-pressed Mesocarp Olein in Sprague-Dawley Rats

Refined red palm-pressed mesocarp olein (PPMO) is recovered from palm-pressed mesocarp fiber, which is a by-product from palm oil mill. Its utilization in food industry is extremely limited even though it contains various phytonutrients. Thus, this study aimed to evaluate its toxicity effects by using the male Sprague-Dawley rat model. The rats were administered with a single dose of 2 g/kg PPMO in an acute toxicity study while administered with 2, 1, or 0.5 g/kg PPMO daily for 28 days in a sub-chronic toxicity study. The mortality, oral LD50 value, clinical observation, body and organ weight, hematological and biochemical analyses, pathological and histopathological examinations were assessed. The overall outcomes indicated that PPMO is non-toxic up to 2 g/kg and considered safe to be used in food application, especially as functional food ingredient and supplement attributed to its phytonutrients. Besides, this study provides an insight in alternative utilization of the wastes from palm oil mill.

The Effect of Methotrexate on Serum Levels of Trace/Mineral Elements in Patients with Psoriatic Arthritis

Psoriatic arthritis is a type of inflammatory arthritis that occurs in some patients with psoriasis. Clinically, low-dose methotrexate was used to treat psoriatic arthritis as a first-line agent. However, the pathogenesis of psoriatic arthritis and the mechanism of methotrexate treating psoriatic arthritis remained unclear. In recent years, a variety of side effects associated with methotrexate have been reported. In order to illuminate the role of trace/mineral elements in the pathogenesis of psoriatic arthritis and the side effect of low-dose methotrexate on blood cells and trace/mineral elements in patients with psoriatic arthritis, 37 psoriatic arthritis patients and healthy 50 people with similar age and gender were enrolled in this study. The blood cells, serum trace/mineral elements, liver function, and kidney function were determined. The results revealed that the level of serum zinc was significantly lower and copper was significantly higher in psoriatic arthritis patients in comparison with healthy control. After giving patients methotrexate intravenously (15 mg weekly), their serum zinc was significantly increased, and copper was significantly decreased with symptoms relieved. Our study provided the evidence that low zinc and high copper might be associated with the pathogenesis of psoriatic arthritis, and the possible mechanism of methotrexate treating psoriatic arthritis was through elevating zinc and reducing copper in serum. Moreover, we demonstrated that low-dose methotrexate could induce liver damage to psoriatic arthritis patients.

Colostrogenesis: Role and Mechanism of the Bovine Fc Receptor of the Neonate (FcRn)

Colostrogenesis is a separate and unique phase of mammary epithelial cell activity occurring in the weeks before parturition and rather abruptly ending after birth in the bovine. It has been the focus of research to define what controls this process and how it produces high concentrations of specific biologically active components important for the neonate. In this review we consider colostrum composition and focus upon components that appear in first milked colostrum in concentrations exceeding that in blood serum. The Fc Receptor of the Neonate (FcRn) is recognized as the major immunoglobulin G (IgG) and albumin binding protein that accounts for the proteins' long half-lives. We integrate the action of the pinocytotic (fluid phase) uptake of extracellular components and merge them with FcRn in sorting endosomes. We define and explore the means of binding, sorting, and the transcytotic delivery of IgG1 while recycling IgG2 and albumin. We consider the means of releasing the ligands from the receptor within the endosome and describe a new secretion mechanism of cargo release into colostrum without the appearance of FcRn itself in colostrum. We integrate the insulin-like growth factor family, some of which are highly concentrated bioactive components of colostrum, with the mechanisms related to FcRn endosome action. In addition to secretion, we highlight the recent findings of a role of the FcRn in phagocytosis and antigen presentation and relate its significant and abrupt change in cellular location after parturition to a role in the prevention and resistance to mastitis infections.

Effects of Fusarium metabolites beauvericin and enniatins alone or in mixture with deoxynivalenol on weaning piglets

The impact of the Fusarium-derived metabolites beauvericin, enniatin B and B1 (EB) alone or in combination with deoxynivalenol (DON) was investigated in 28-29 days old weaning piglets over a time period of 14 days. The co-application of EB and DON (EB + DON) led to a significant decrease in the weight gain of the animals. Liver enzyme activities in plasma were significantly decreased at day 14 in piglets receiving the EB + DON-containing diet compared to piglets receiving the control diet. All mycotoxin-contaminated diets led to moderate to severe histological lesions in the jejunum, the liver and lymph nodes. Shotgun metagenomics revealed a significant effect of EB-application on the gut microbiota. Our results provide novel insights into the harmful impact of emerging mycotoxins alone or with DON on the performance, gut health and immunological parameters in pigs.

Neutrophil-mediated oxidative stress and albumin structural damage predict COVID-19-associated mortality

Human serum albumin (HSA) is the frontline antioxidant protein in blood with established anti-inflammatory and anticoagulation functions. Here, we report that COVID-19-induced oxidative stress inflicts structural damages to HSA and is linked with mortality outcome in critically ill patients. We recruited 39 patients who were followed up for a median of 12.5 days (1–35 days), among them 23 had died. Analyzing blood samples from patients and healthy individuals (n=11), we provide evidence that neutrophils are major sources of oxidative stress in blood and that hydrogen peroxide is highly accumulated in plasmas of non-survivors. We then analyzed electron paramagnetic resonance spectra of spin-labeled fatty acids (SLFAs) bound with HSA in whole blood of control, survivor, and non-survivor subjects (n=10–11). Non-survivors’ HSA showed dramatically reduced protein packing order parameter, faster SLFA correlational rotational time, and smaller S/W ratio (strong-binding/weak-binding sites within HSA), all reflecting remarkably fluid protein microenvironments. Following loading/unloading of 16-DSA, we show that the transport function of HSA may be impaired in severe patients. Stratified at the means, Kaplan–Meier survival analysis indicated that lower values of S/W ratio and accumulated H₂O₂ in plasma significantly predicted in-hospital mortality (S/W≤0.15, 81.8% (18/22) vs. S/W>0.15, 18.2% (4/22), p=0.023; plasma [H₂O₂]>8.6 μM, 65.2% (15/23) vs. 34.8% (8/23), p=0.043). When we combined these two parameters as the ratio ((S/W)/[H₂O₂]) to derive a risk score, the resultant risk score lower than the mean (<0.019) predicted mortality with high fidelity (95.5% (21/22) vs. 4.5% (1/22), log-rank χ²=12.1, p=4.9×10⁻⁴). The derived parameters may provide a surrogate marker to assess new candidates for COVID-19 treatments targeting HSA replacements and/or oxidative stress.

Protein Nutritional Status and Frailty: A Mendelian Randomization Study

BACKGROUND

Observational studies have suggested that better protein nutritional status may contribute to prevention of frailty.

OBJECTIVE

We sought to examine this hypothesis using a Mendelian randomization (MR) analysis.

METHODS

We conducted a two-sample MR study using GWAS summary statistics data of the UK Biobank. We applied genetically predicted serum albumin as a primary exposure measure and serum total protein as a secondary exposure measure. The outcome measure was the Rockwood frailty index (FI) based on 49 deficits from 356,432 individuals (53.3% of them were women, with a mean ± SD age of 56.7 ± 8.0 y. The association between serum protein measures and FI was mainly analyzed by use of the inverse variance weighted method.

RESULTS

A genetically predicted serum albumin concentration was not statistically significantly associated with FI in the full sample. However, in women, we observed a preventive association between genetically predicted serum albumin and FI (β = -0.172 per g/L; 95% CI: -0.336, -0.007; P = 0.041). In the full sample, genetically predicted serum total protein was inversely associated with FI (β: -0.153 per g/L; 95% CI: -0.251, -0.056; P = 0.002). In both women and men, higher serum total protein was significantly inversely associated with FI; regression coefficients were -0.148 per g/L (95% CI: -0.287, -0.009; P = 0.037) for women, -0.154 per g/L (95% CI: -0.290, -0.018; P = 0.027) for men.

CONCLUSIONS

The present MR study implies that better protein nutritional status modestly contributes to reducing the risk of frailty.

Pharmacokinetic Engineering of OX40-Blocking Anticalin Proteins Using Monomeric Plasma Half-Life Extension Domains

Anticalin^® proteins have been proven as versatile clinical stage biotherapeutics. Due to their small size (∼20 kDa), they harbor a short intrinsic plasma half-life which can be extended, e.g., by fusion with IgG or Fc. However, for antagonism of co-immunostimulatory Tumor Necrosis Factor Receptor Superfamily (TNFRSF) members in therapy of autoimmune and inflammatory diseases, a monovalent, pharmacokinetically optimized Anticalin protein format that avoids receptor clustering and therefore potential activation is favored. We investigated the suitability of an affinity-improved streptococcal Albumin-Binding Domain (ABD) and the engineered Fab-selective Immunoglobulin-Binding Domain (IgBD) SpGC3Fab for plasma Half-Life Extension (HLE) of an OX40-specific Anticalin and bispecific Duocalin proteins, neutralizing OX40 and a second co-immunostimulatory TNFRSF member. The higher affinity of ABD fusion proteins to human serum albumin (HSA) and Mouse Serum Albumin (MSA), with a 4 to 5-order of magnitude lower K_D compared with the binding affinity of IgBD fusions to human/mouse IgG, translated into longer terminal plasma half-lives (t_1/2). Hence, the anti-OX40 Anticalin-ABD protein reached t_1/2 values of ∼40 h in wild-type mice and 110 h in hSA/hFcRn double humanized mice, in contrast to ∼7 h observed for anti-OX40 Anticalin-IgBD in wild-type mice. The pharmacokinetics of an anti-OX40 Anticalin-Fc fusion protein was the longest in both models (t_1/2 of 130 h and 146 h, respectively). Protein formats composed of two ABDs or IgBDs instead of one single HLE domain clearly showed longer presence in the circulation. Importantly, Anticalin-ABD and -IgBD fusions showed OX40 receptor binding and functional competition with OX40L-induced cellular reactivity in the presence of albumin or IgG, respectively. Our results suggest that fusion to ABD or IgBD can be a versatile platform to tune the plasma half-life of Anticalin proteins in response to therapeutic needs.

Effect of dietary folic acid and energy density on immune response, gut morphology, and oxidative status in blood and breast muscle of broiler chickens

Folic acid (FA) plays essential roles in many metabolic functions and has been reported to have antioxidant effects. Therefore, dietary supplementation with high levels of FA may improve gut health and prevent potential oxidative stress caused by feeding a high energy density diet to broiler chickens. Broiler chickens were assigned into eight treatments, consisting of either a normal energy (NE) or high energy (HE) density diet, and four FA levels (2.2, 5, 10, and 15 ppm). Data were analyzed by SAS 16 GLM procedure. Birds-fed HE diets had increased (P < 0.05) plasma concentrations of calcium and albumin but reduced (P < 0.005) weights of ceca and bursa compared with those fed NE diets. Dietary supplementation with 10 ppm FA significantly increased (P < 0.05) birds’ heart weight and bile acid concentration. Folic acid and energy density interactions were significant for jejunal villus height (VH; P = 0.0226), villus width (VW; P < 0.0001), and crypt depth (CD; P = 0.0332). Among the NE group, birds fed 5–15 ppm FA had reduced (P < .0001) VW, while in the HE groups, 15 ppm FA supplementation resulted in an increased jejunal VH (P = 0.0317) compared with other treatments. In conclusion, dietary supplementation with increased levels of FA in HE diets could be beneficial for the intestinal health of broiler chickens.

Preoperative Serum Prealbumin Level and Adverse Prognosis in Patients With Hepatocellular Carcinoma After Hepatectomy: A Meta-Analysis

Background

Prealbumin is a sensitive indicator of liver function and nutritional status.

Objectives

This meta-analysis aimed to examine the association of the serum prealbumin level with the prognosis of patients with hepatocellular carcinoma (HCC) undergoing hepatectomy.

Methods

We comprehensively searched the PubMed, Embase, Wanfang, China Academic Journals (CNKI), and SinoMed databases up to September 1, 2021. Eligible studies should report the association of the serum prealbumin level with prognosis and provide the multivariable-adjusted risk estimates of the outcomes of interest in HCC patients undergoing hepatectomy.

Results

A total of 11 studies with 7,442 HCC patients were identified and analyzed. Meta-analysis of a fixed effects model showed that a low serum prealbumin level was associated with poor overall survival [hazard ratio (HR) = 1.54, 95% confidence interval (CI) = 1.42-1.68], recurrence-free survival (HR = 1.34, 95% CI = 1.17-1.52), and a higher risk of postoperative hepatic insufficiency (HR = 2.21; 95% CI = 1.36-3.60) in HCC patients. Sensitivity and subgroup analyses confirmed the robustness of low serum prealbumin in predicting poor overall survival.

Conclusions

This meta-analysis indicated that a low preoperative serum prealbumin level was significantly associated with adverse prognosis in HCC patients undergoing hepatectomy.

Study protocol for an open labelled randomised controlled trial of perioperative oral nutrition supplement in breast and colorectal cancer patients undergoing elective surgery

Background

While it is well established that perioperative use of oral nutrition supplement (ONS) improves nutrition status among severely malnourished surgical cancer patients, the evidence requires further substantiation for non-severely malnourished patients with cancer. This protocol paper presents the rationale and design of a randomised controlled trial to evaluate the effectiveness of preoperative as well as an extended 90-day postoperative use of ONS on nutritional and clinical outcomes among patients undergoing elective surgery for breast and colorectal cancer.

Methods

Patients with primary breast and colorectal cancer undergoing elective surgery are recruited from two tertiary hospitals. Eligible patients are assigned into one of the three intervention arms: (i) Group SS will receive ONS in addition to their normal diet up to 14 days preoperatively and postoperatively up to discharge; (ii) Group SS-E will receive ONS in addition to their normal diet up to 14 days preoperatively, postoperatively up to discharge and for an extended 90 days after discharge; and (iii) Group DS will receive ONS in addition to their normal diet postoperatively up to discharge from the hospital. The ONS is a standard formula fortified with lactium to aid in sleep for recovery. The primary endpoints include changes in weight, body mass index (BMI), serum albumin and prealbumin levels, while secondary endpoints are body composition (muscle and fat mass), muscle strength (handgrip strength), energy and protein intake, sleep quality, haemoglobin, inflammatory markers (transferrin, high sensitivity C-reactive protein, interleukin-6), stress marker (saliva cortisol), length of hospital stay and postoperative complication rate.

Discussion

This trial is expected to provide evidence on whether perioperative supplementation in breast and colorectal cancer patients presenting with high BMI and not severely malnourished but undergoing the stress of surgery would be beneficial in terms of nutritional and clinical outcomes.

Trial registration

ClinicalTrial.gov NCT04400552. Registered on 22 May 2020, retrospectively registered

Supplementary Information

The online version contains supplementary material available at 10.1186/s13063-021-05716-5.

An artificial intelligence algorithm for analyzing acetaminophen-associated toxic hepatitis

INTRODUCTION

Very little artificial intelligence (AI) work has been performed to investigate acetaminophen-associated hepatotoxicity. The objective of this study was to develop an AI algorithm for analyzing weighted features for toxic hepatitis after acetaminophen poisoning.

METHODS

The medical records of 187 patients with acetaminophen poisoning treated at Chang Gung Memorial Hospital were reviewed. Patients were sorted into two groups according to their status of toxic hepatitis. A total of 40 clinical and laboratory features recorded on the first day of admission were selected for algorithm development. The random forest classifier (RFC) and logistic regression (LR) were used for artificial intelligence algorithm development.

RESULTS

The RFC-based AI model achieved the following results: accuracy = 92.5 ± 2.6%; sensitivity = 100%; specificity = 60%; precision = 92.3 ± 3.4%; and F1 = 96.0 ± 1.8%. The area under the receiver operating characteristic curve (AUROC) was approximately 0.98. The LR-based AI model achieved the following results: accuracy = 92.00 ± 2.9%; sensitivity = 100%; specificity = 20%; precision = 92.8 ± 3.4%; recall = 98.8 ± 3.4%; and F1 = 95.6 ± 1.5%. The AUROC was approximately 0.68. The weighted features were calculated, and the 10 most important weighted features for toxic hepatitis were aspartate aminotransferase (ALT), prothrombin time, alanine aminotransferase (AST), time to hospital, platelet count, lymphocyte count, albumin, total bilirubin, body temperature and acetaminophen level.

CONCLUSION

The top five weighted features for acetaminophen-associated toxic hepatitis were ALT, prothrombin time, AST, time to hospital and platelet count.

Unresolved inflammation during hospitalization is associated with post-discharge institutionalization and mortality in geriatric rehabilitation inpatients: The RESORT cohort

BACKGROUND

Inflammation contributes to adverse health outcomes in community-dwelling populations. Little is known about inflammation in hospitalized older adults and its association with adverse outcomes. This study aimed to evaluate the association of the inflammatory markers C-reactive protein (CRP) and albumin measured during acute and geriatric rehabilitation hospitalization with institutionalization and mortality in geriatric rehabilitation inpatients.

METHODS

Within the REStORing health of acutely unwell adulTs (RESORT) cohort, CRP and albumin were measured as part of usual care during acute and geriatric rehabilitation hospitalization. Inflammatory markers are presented as median, peak (CRP: maximum; albumin: minimum), variation (interquartile range) and direction of change (increased CRP or decreased albumin: positive or negative difference between last measurement and median of preceding measurements). Logistic regression was used to determine the associations between inflammatory markers and institutionalization at three-month and all-cause mortality at three- and twelve-month post-discharge.

RESULTS

Geriatric rehabilitation inpatients (n = 1846) with a median age of 83.3 years (interquartile range 77.6-88.3) and 56.6% of female were included. Increased CRP during geriatric rehabilitation was associated with institutionalization. Higher median, peak and increased levels of CRP during geriatric rehabilitation but not during acute hospitalization were associated with higher mortality. Lower CRP variation during acute hospitalization but higher CRP variation during geriatric rehabilitation was associated with higher mortality. Lower median level of albumin during both hospitalizations were associated with higher mortality.

CONCLUSIONS

Inflammation characterized by lower albumin during acute hospitalization and, higher CRP and lower albumin during geriatric rehabilitation was associated with mortality in geriatric rehabilitation inpatients. Increased CRP during geriatric rehabilitation was associated with institutionalization. Unresolved inflammation in geriatric rehabilitation might indicate ongoing disease activity leading to adverse outcomes.

Prognostic nutritional index predicts clinical outcomes in patients with cerebral venous sinus thrombosis

Background

Lower prognostic nutritional index (PNI) is related to the poor prognosis of cardiovascular diseases. However, little is known about PNI and its relationship with the prognosis of cerebral venous sinus thrombosis (CVST).

Methods

CVST patients were retrospectively identified from January 2013 till June 2019. Patients in the acute / subacute phase were selected as subjects. Poor prognosis was defined as a modified Rankin Scale (mRS) of 3–6. Multivariate logistic regression analysis was used to confirm if lower PNI was associated with a poor prognosis.

Results

A total of 297 subjects with follow-up data were enrolled. Thirty-three (11.1%) had a poor outcome. Multivariate logistic regression analysis suggested that PNI was an important predictive factor of poor outcome in acute/subacute CVST (odds ratio, 0.903; 95% CI, 0.833–0.978; P = 0.012). The optimal cut-off value for predicting the poor prognosis of PNI was 44.2. Kaplan-Meier analysis and log-rank test suggested that the lower the PNI value, the higher the mortality rate (P < 0.001). In addition, the nomogram that was set up showed that lower PNI was an index of poor prognosis. The c-index for acute/subacute patients with CVST was 0.872.

Conclusion

Lower PNI is correlated with a higher risk of adverse clinical outcomes in patients with acute/subacute CVST.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12883-021-02436-w.

Prognostic impact of follow-up serum albumin after acute myocardial infarction

Aims

Previous studies have suggested that low serum albumin (LSA) at admission for acute myocardial infarction (AMI) is associated with adverse in‐hospital outcomes. The aim of this study was to investigate whether LSA in the remote phase after AMI is prognostic for long‐term outcomes.

Methods and results

This was a single‐centre, retrospective study of consecutive patients admitted for AMI from 2008 to 2016. Serum albumin concentrations were measured serially at admission and 1 year after discharge in Japanese patients. Occurrence of a composite of hospitalization for heart failure and cardiovascular death was the primary endpoint. The prognostic impact of remote LSA, defined as a serum albumin level < 3.8 g/dL at 1 year after discharge, was investigated with a multivariate‐adjusted Cox model. Among 1424 subjects analysed, 289 (20.3%) had LSA at admission, and 165 (11.6%) had LSA at 1 year after discharge. During follow‐up (median: 4.1 years), the primary endpoint occurred in 31/165 (18.8%) patients with remote LSA and 42/1259 (3.3%) patients without it [adjusted hazard ratio (aHR), 2.76; 95% confidence interval (CI), 1.32 to 5.72; P = 0.007]. The all‐cause death rate was 29.7% (49/165) in patients with remote LSA and 4.3% (54/1259) in patients without it (aHR, 4.02; 95% CI, 2.36 to 6.87; P < 0.001). The prognostic impact of remote LSA was consistent across albumin status in the acute phase of AMI.

Conclusions

Regardless of albumin status in the acute phase of AMI, LSA in the remote phase after AMI was significantly associated with long‐term adverse outcomes.

Albumin is an interface between blood plasma and cell membrane, and not just a sponge

Albumin is the most abundant protein in blood plasma and acts as a carrier for many circulating molecules. Hypoalbuminaemia, mostly caused by either renal or liver disease or malnutrition, can perturb vascular homeostasis and is involved in the development of multiple diseases. Here we review four functions of albumin and the consequences of hypoalbuminaemia on vascular homeostasis. (i) Albumin is the main determinant of plasma colloid osmotic pressure. Hypoalbuminaemia was therefore thought to be the main mechanism for oedema in nephrotic syndrome (NS), however, experimental studies showed that intrarenal mechanisms rather than hypoalbuminaemia determine formation and, in particular, maintenance of oedema. (ii) Albumin functions as an interface between lysophosphatidylcholine (LPC) and circulating factors (lipoproteins and erythrocytes) and the endothelium. Consequently, hypoalbuminaemia results in higher LPC levels in lipoproteins and erythrocyte membrane, thereby increasing atherosclerotic properties of low-density lipoprotein and blood viscosity, respectively. Furthermore, albumin dose-dependently restores LPC-induced inhibition of vasodilation. (iii) Hypoalbuminaemia impacts on vascular nitric oxide (NO) signalling by directly increasing NO production in endothelial cells, leading to reduced NO sensitivity of vascular smooth muscle cells. (iv) Lastly, albumin binds free fatty acids (FFAs). FFAs can induce vascular smooth muscle cell apoptosis, uncouple endothelial NO synthase and decrease endothelium-dependent vasodilation. Unbound FFAs can increase the formation of reactive oxygen species by mitochondrial uncoupling in multiple cell types and induce hypertriglyceridemia in NS. In conclusion, albumin acts as an interface in the circulation and hypoalbuminaemia impairs multiple aspects of vascular function that may underlie the association of hypoalbuminaemia with adverse outcomes. However, hypoalbuminaemia is not a key to oedema in NS. These insights have therapeutic implications.

Prognostic value of C-reactive protein/albumin ratio in hypertensive COVID-19 patients

OBJECTIVES

The aim of this study was to investigate the relationship between the C-reactive protein/albumin ratio and the prognosis of hypertensive COVID-19 patients.

METHODS

It was designed as a single center retrospective study. PCR positive COVID-19 patients who were followed up in the intensive care unit (ICU) and received antihypertensive treatment were included in the study. The patients were divided into two groups as survivor and non-survivor. C-reactive protein/albumin (CAR) ratios of the patients were compared. The cut-off value was determined as a mortality predictor. The effect of CAR on mortality was evaluated using Logistic Regression analysis.

RESULTS

281 patients were included in the study. Groups consisted of 135 (non-survivor) and 146 (survivor) patients. CAR was significantly higher in the non-survivor group (p<0.001). The area under the ROC curve for CAR for mortality was 0.807, with sensitivity of 0.71 and specificity of 0.71. The cut-off value for CAR was calculated as 56.62. In logistic regression analysis, CAR increases mortality 4.9 times compared to the cut-off value.

CONCLUSION

CAR is a powerful and independent prognostic marker for predicting mortality and disease progression in hypertensive COVID-19 patients.

The role of lactate dehydrogenase-to-albumin ratio in clinical evaluation of adult-onset Still's disease

OBJECTIVES

The aim of the study is to evaluate the importance of lactate dehydrogenase-to-albumin ratio (LAR) in patients with adult-onset Still's disease (AOSD) and to investigate the relationship between this ratio and clinical laboratory variables.

METHODS

The study design was retrospective cross-sectional. The demographic and clinical data, laboratory results and imaging findings were documented. Univariate and multinomial logistic regression analyses were performed to find the predictors, which could be useful to define the ferritin level and organ involvement. Receiver-operating characteristic (ROC) analysis was used to clarify the diagnostic ability of the LAR for ferritin level and organ involvement.

RESULTS

Fifty-eight patients with AOSD were evaluated. When patients were divided into two groups according to the serum ferritin level with a cut-off of 1500 ng/dL, lymphocyte count and albumin level were significantly less in patients who had higher ferritin levels (P = .015 and P = .005). In multinominal logistic regression analysis, AST, LDH and LAR were found as predictors for ferritin levels. When we compared LAR between patients with and without organ involvement, higher LAR was found in patients with HM, SM, serositis and MAS. Also, LAR was significantly higher in patients with higher ferritin levels (≥1500 ng/dL) than those without (P < .001). In ROC analysis, the cut-off point of LAR predicting the ferritin level was determined as 80.75 with 83.7% sensitivity and 80.0% specificity (AUC = 0.89, 95% CI 0.79-0.98, P < .001).

CONCLUSION

LAR can be a valuable inflammatory marker to determine AOSD patients with organ involvement and higher ferritin level.

Predictive value of Albumin-Bilirubin grade for intravenous immunoglobulin resistance in a large cohort of patients with Kawasaki disease: a prospective study

BACKGROUND

Intravenous immunoglobulin (IVIG) resistance prediction is one of the primary clinical issues and study hotspots in KD. This study aimed to prospectively investigate the value of albumin-bilirubin grade (ALBI) in predicting IVIG resistance in KD and to assess whether ALBI has more predictive value or accuracy than either ALB or TBil alone in predicting IVIG resistance.

METHODS

A total of 823 patients with KD were prospectively enrolled. The clinical and laboratory data were compared between the IVIG-response group (n = 708) and the IVIG-resistance group (n = 115). Multivariate logistic regression analysis was performed to identify the independent risk factors for IVIG resistance. Receiver operating characteristic (ROC) curves analysis was applied to assess the validity of ALBI, ALB, and TBil in predicting IVIG resistance.

RESULTS

ALBI was significantly higher in patients with IVIG resistance and was identified as an independent risk factor for IVIG resistance in KD. The parameter of ALBI ≥ - 2.57 (AUC: 0.705, 95 %CI: 0.672-0.736), ALB ≤ 33.0 g/L (AUC: 0.659, 95 %CI: 0.626-0.692), and TBil ≥ 16.0µmol/L (AUC: 0.626, 95 %CI: 0.592-0.659), produced a sensitivity, specificity, PPV, and NPV of 0.617, 0.657, 0.226 and 0.914; 0.374, 0.850, 0.289 and 0.893; 0.269, 0.941, 0.425 and 0.888, respectively.

CONCLUSIONS

A higher ALBI was an independent risk factor for IVIG resistance in KD. It yielded better predictive ability than ALB and TBil alone for initial IVIG resistance.

Linear Association Between Hypoalbuminemia and Increased Risk of Acute Respiratory Distress Syndrome in Critically Ill Adults

Supplemental Digital Content is available in the text.

We hypothesized that low serum albumin would contribute to pulmonary edema formation, thereby independently increasing the risk of developing acute respiratory distress syndrome in critically ill patients.

High resolution stereolithography fabrication of perfusable scaffolds to enable long-term meso-scale hepatic culture for disease modeling

Microphysiological systems (MPS), comprising human cell cultured in formats that capture features of the three-dimensional (3D) microenvironments of native human organs under microperfusion, are promising tools for biomedical research. Here we report the development of a mesoscale physiological system (MePS) enabling the long-term 3D perfused culture of primary human hepatocytes at scales of over 10⁶cells per MPS. A central feature of the MePS, which employs a commercially-available multiwell bioreactor for perfusion, is a novel scaffold comprising a dense network of nano- and micro-porous polymer channels, designed to provide appropriate convective and diffusive mass transfer of oxygen and other nutrients while maintaining physiological values of shear stress. The scaffold design is realized by a high resolution stereolithography fabrication process employing a novel resin. This new culture system sustains mesoscopic hepatic tissue-like cultures with greater hepatic functionality (assessed by albumin and urea synthesis, and CYP3A4 activity) and lower inflammation markers compared to comparable cultures on the commercial polystyrene scaffold. To illustrate applications to disease modeling, we established an insulin-resistant phenotype by exposing liver cells to hyperglycemic and hyperinsulinemic media. Future applications of the MePS include the co-culture of hepatocytes with resident immune cells and the integration with multiple organs to model complex liver-associated diseases.

Serum Albumin: A Multifaced Enzyme

Human serum albumin (HSA) is the most abundant protein in plasma, contributing actively to oncotic pressure maintenance and fluid distribution between body compartments. HSA acts as the main carrier of fatty acids, recognizes metal ions, affects pharmacokinetics of many drugs, provides the metabolic modification of some ligands, renders potential toxins harmless, accounts for most of the anti-oxidant capacity of human plasma, and displays esterase, enolase, glucuronidase, and peroxidase (pseudo)-enzymatic activities. HSA-based catalysis is physiologically relevant, affecting the metabolism of endogenous and exogenous compounds including proteins, lipids, cholesterol, reactive oxygen species (ROS), and drugs. Catalytic properties of HSA are modulated by allosteric effectors, competitive inhibitors, chemical modifications, pathological conditions, and aging. HSA displays anti-oxidant properties and is critical for plasma detoxification from toxic agents and for pro-drugs activation. The enzymatic properties of HSA can be also exploited by chemical industries as a scaffold to produce libraries of catalysts with improved proficiency and stereoselectivity for water decontamination from poisonous agents and environmental contaminants, in the so called “green chemistry” field. Here, an overview of the intrinsic and metal dependent (pseudo-)enzymatic properties of HSA is reported to highlight the roles played by this multifaced protein.

One ring is not enough to rule them all. Albumin-dependent ABCG2-mediated transport of chlorophyll-derived photosensitizers

Breast cancer resistance protein (BCRP, ABCG2) is a member of the ATP-binding-cassette (ABC) superfamily of membrane transporters. It is involved in the efflux of a broad range of xenobiotics of highly diverse structures. BCRP activity greatly influences drug distribution in vivo and is often associated with cancer multidrug resistance, which is observed in the case of both chemotherapy and photodynamic therapy. The set of ABCG2 substrates includes porphyrins and chlorins such as heme, hemin, protoporphyrin IX, chlorin e6, pheophorbide a, and their derivatives. Here we provide an evidence that magnesium- and zinc-substituted derivatives of pheophorbide a, which are very promising photosensitizers for use in photodynamic therapy, are also recognized and transported by ABCG2. Interestingly, despite minor structural differences, they clearly differ in the transport rate, both between each other and compared to pheophorbide a. In addition, their transport rate, like those of other structurally similar compounds, is strictly dependent on the level of serum albumin in the extracellular environment. The results that we present here are crucial for the use of metal-substituted pheophorbides in clinical practice but also provide an important insight into the mechanism of porphyrin transport by ABCG2.

Identification of miR-199a-5p, miR-214-3p and miR-99b-5p as Fibrosis-Specific Extracellular Biomarkers and Promoters of HSC Activation

Liver fibrosis is characterized by the accumulation of extracellular matrix (ECM) resulting in the formation of fibrous scars. In the clinic, liver biopsies are the standard diagnostic method despite the potential for clinical complications. miRNAs are single-stranded, non-coding RNAs that can be detected in tissues, body fluids and cultured cells. The regulation of many miRNAs has been linked to tissue damage, including liver fibrosis in patients, resulting in aberrant miRNA expression/release. Experimental evidence also suggests that miRNAs are regulated in a similar manner in vitro and could thus serve as translational in vitro–in vivo biomarkers. In this work, we set out to identify and characterize biomarkers for liver fibrosis that could be used in vitro and clinically for research and diagnostic purposes. We focused on miRNAs released from hepatic 3D cultures exposed to methotrexate (MTX), which causes fibrosis, and acetaminophen (APAP), an acute hepatotoxicant with no clinically relevant association to liver fibrosis. Using a 3D in vitro model, we corroborated compound-specific responses as we show MTX induced a fibrotic response, and APAP did not. Performing miRNA-seq of cell culture supernatants, we identified potential miRNA biomarkers (miR-199a-5p, miR-214-3p, niRNA-125a-5p and miR-99b-5p) that were associated with a fibrotic phenotype and not with hepatocellular damage alone. Moreover, transfection of HSC with miR-199a-5p led to decreased expression of caveolin-1 and increased α-SMA expression, suggesting its role in HSC activation. In conclusion, we propose that extracellular miR-214-3p, miR-99b-5p, miR-125a-5p and specifically miR-199a-5p could contribute towards a panel of miRNAs for identifying liver fibrosis and that miR-199a-5p, miR-214-3p and miR-99b-5p are promoters of HSC activation.

Hypoalbuminemia as a prognostic biomarker for higher mortality and treatment complications in acute myeloid leukemia

Older age and poor performance status lead to worse outcomes in acute myeloid leukemia (AML) patients. Hypoalbuminemia is a negative predictor of morbidity and mortality in several malignancies. We evaluated the relationship between baseline serum albumin levels on treatment-related complications, as well as short-term mortality and overall survival (OS) in 756 newly diagnosed AML patients. We conducted a retrospective multicenter study to examine treatment-related complications and OS according to pretreatment serum albumin levels: normal albumin ≥3.5 g/dl, marked hypoalbuminemia <2.5 g/dl, and hypoalbuminemia 2.5-3.4 g/dl. In an adjusted multivariate analysis, a lower baseline albumin was independently associated with a higher number of grade ≥3 complications when adjusting for age, secondary AML, sex and intensive treatment. When comparing normal to markedly low albumin levels, the estimated mean number of complications increases by a factor of 1.35. Patients who had a normal baseline albumin had a 30 day-mortality rate of 4.8%, which was significantly lower compared with patients with hypoalbuminemia (16.5%) and marked hypoalbuminemia (33.9%; p < 0.01). Similarly, 60-day mortality rate was significantly higher in the hypoalbuminemia group (24.0%) and marked hypoalbuminemia group (45%) compared with normal albumin group (8.3%; p < 0.01). Patients with lower baseline albumin levels have increased treatment-related morbidity and mortality, suggesting that pre-treatment serum albumin is an important independent prognostic marker.

Reduced serum albumin as a risk factor for poor prognosis in critically ill patients receiving renal replacement therapy

Background

Albumin is the primary body protein, which can predict the poor prognosis of several critical diseases. However, there are a few scientific studies on the relationship between albumin and the prognosis of dialysis patients. This study aims to explore the impact of hypoalbuminemia on the prognosis of critically ill patients with acute kidney injury (AKI) receiving continuous renal replacement therapy (CRRT).

Methods

This was a secondary study. Clinical, biochemical, and 28-day and 90-day mortality rates for critical patients with AKI who received CRRT between 2009 and 2016 were searched from the database to determine the effect of hypoalbuminemia on poor outcomes by univariate, multivariate, smooth curve fitting, and subgroup analysis.

Results

A total of 837 participants were enrolled in this study. Multivariate Cox proportional hazard regression analysis showed that hypoalbuminemia was associated with both 28-day and 90-day mortality risks after full adjustment for confounding variables, with an adjusted hazard ratio (95% confidence interval) of 0.63 (0.50–0.80) and 0.63 (0.51–0.78), respectively for each 1 g/dL increase of albumin. Stratified analysis showed that hypoalbuminemia was not associated with poor prognosis in oliguria.

Conclusion

Hypoalbuminemia is associated with poor prognosis in critically ill AKI patients with CRRT; therefore, measuring albumin may be helpful for predicting the prognosis. However, in those with oliguria, this conclusion is not valid.

Prevalence of Preoperative Lower Extremity Deep Vein Thrombosis in Bilateral Calcaneal Fractures

There are no studies on epidemiologic characteristics of deep vein thrombosis (DVT), when specified at in patients with bilateral calcaneal fractures. This study aimed to address the preoperative DVT in bilateral calcaneal fractures. Between October 2014 and December 2018, adult patients presenting with bilateral calcaneal fractures and having preoperative Duplex ultrasound (DUS) of bilateral lower extremities for detection of DVT were included. Their medical data were collected, with regards to demographics, comorbidities, injury-related data and biomarkers. Baseline characteristics between patients with and without DVT were compared using bivariate tests. The further multivariate logistics regression analysis was conducted to identify independent factors associated with DVT. In total, 258 patients with bilateral calcaneal fractures were included, with 21 (8.1%) having preoperative DVT, diagnosed at 7.7 ± 4.2 days after injury. The prevalence rate of proximal DVT was 1.9% and of distal DVT was 6.2%. Thirty five thrombi were found, with 6 (17.1%) in proximal veins and 29 (82.9%) in distal veins. Nine patients had DVTs in multiple veins, and 2 patients had bilateral DVTs. The multivariate analyses showed history of allergy (odds ratio [OR] = 2.17), concurrent other fractures (OR = 4.53), prolonged time since injury (for each day, OR = 1.16), elevated plasma D-dimer level (≥1.73 vs <1.73 mg/L, OR = 3.74) and reduced albumin level (<34.2 g/L vs ≥34.2 g/L, OR = 2.92) were independent factors associated with DVT. Multiple factors were identified to be associated with DVT and greater consideration should be given to the use of pharmacologic prophylaxis in patients involving these factors, to reduce DVT occurrence.

Fluorescent kinase inhibitors as probes in cancer

Fluorescent dyes attached to kinase inhibitors (KIs) can be used to probe kinases in vitro, in cells, and in vivo. Ideal characteristics of the dyes vary with their intended applications. Fluorophores used in vitro may inform on kinase active site environments, hence the dyes used should be small and have minimal impact on modes of binding. These probes may have short wavelength emissions since blue fluorophores are perfectly adequate in this context. Thus, for instance, KI fragments that mimic nucleobases may be modified to be fluorescent with minimal perturbation to the kinase inhibitor structure. However, progressively larger dyes, that emit at longer wavelengths, are required for cellular and in vivo work. In cells, it is necessary to have emissions above autofluorescence of biomolecules, and near infrared dyes are needed to enable excitation and observation through tissue in vivo. This review is organized to describe probes intended for applications in vitro, in cells, then in vivo. The readers will observe that the probes featured tend to become larger and responsive to the near infared end of the spectrum as the review progresses. Readers may also be surprised to realize that relatively few dyes have been used for fluorophore-kinase inhibitor conjugates, and the area is open for innovations in the types of fluorophores used.