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

Usefulness of Psoas Muscle Cross-Sectional Area in Evaluating Physical Performance in Patients with Liver Cirrhosis

Objectives To investigate the relationship between the psoas muscle cross-sectional area and physical performance in patients with liver cirrhosis. Methods This study analyzed ambulatory patients with liver cirrhosis aged < 65 years, who underwent abdominal computed tomography (CT) and Short Physical Performance Battery (SPPB) tests from December 2018 to December 2019. A total of 46 patients (36 men, 10 women) were included. In abdominal CT scans, the psoas muscle cross-sectional area (mm²) was measured at the distal end-plate level of the L4 vertebral body and normalized by dividing by height (m). Physical performance was evaluated using SPPB. A correlation analysis between the psoas muscle cross-sectional area and SPPB was performed. Kruskal-Wallis test was used to determine differences in the psoas muscle cross-sectional area and SPPB according to the Child-Pugh classification. Multiple regression analysis was performed to determine factors affecting SPPB. Results The correlation coefficient between the psoas muscle cross-sectional area and SPPB was 0.459 at the P < 0.01 level. No difference was observed in the psoas muscle cross-sectional area and SPPB according to the Child-Pugh classification. The psoas muscle cross-sectional area was a factor affecting SPPB in multiple regression analysis. Conclusions Abdominal CT is an essential diagnostic tool in patients with liver cirrhosis. Ambulatory patients with liver cirrhosis aged < 65 years could have reduced physical performance. In this study, the psoas muscle cross-sectional area was correlated with physical performance and was a factor affecting physical performance. The psoas muscle cross-sectional area and physical performance should be evaluated in patients with liver cirrhosis.

Pericardial fluid proteomic label-free quantification of differentially expressed proteins in ischemic heart disease patients with systolic dysfunction by nano-LC-ESI-MS/MS analysis

Left ventricular systolic dysfunction (LVSD) is common in patients with pre-existing ischemic heart disease (IHD) and myocardial infarction. An untargeted proteomic approach is used to improve the understanding of the molecular mechanisms associated with LVSD and to find out potential proteomic signatures in pericardial fluid. The pericardial fluid of IHD (n = 45) patients was grouped into two categories according to the left ventricular ejection fraction, LVEF ≥45 (n = 33) and LVEF <45 (n = 12), and analyzed by using nano-liquid chromatography-mass spectrometry (nano-LC-MS/MS) technique. The nano-LC-MS/MS analysis resulted in the identification of 709 pericardial fluid (PF) proteins in both normal and impaired systolic functional groups (LVEF ≥45 vs. LVEF <45). Sixteen proteins were found to be differentially expressed (p < 0.05, fold change >2) including 12 down-regulated and 4 up-regulated in the impaired systolic functional group (LVEF <45) compared to the normal group (LVEF ≥45). Among the differentially expressed proteins the inflammatory marker albumin, atherosclerosis marker apolipoprotein A-IV and hedgehog-interacting protein marker of angiogenesis were predominantly associated with the impaired LVEF <45 group. KEGG pathway analysis revealed that the hedgehog (Hh) signalling pathway is up-regulated in LVSD reflecting the underlying molecular and pathophysiological processes.

K-Means Clustering to Elucidate Vulnerable Subpopulations Among Medicare Patients Undergoing Total Joint Arthroplasty

BACKGROUND

The role of preoperative laboratory values for risk stratification following joint arthroplasty is currently ambiguous. In order to improve upon existing risk stratification within joint arthroplasty, this study sought to define novel phenotypes of total hip or total knee arthroplasty patients based entirely on preoperative laboratory measures. These phenotypes ("clusters") were compared to elucidate statistically and clinically significant differences in outcomes.

METHODS

A total of 134,252 patients were gathered from the National Surgical Quality Improvement Program database between 2005 and 2015. "K-means" with 3 clusters was applied using 9 preoperative laboratory values: sodium, blood urea nitrogen (BUN), creatinine, albumin, bilirubin, white blood cell count, hematocrit, platelet count, and international normalized ratio of prothrombin values (INR). Outcome measures included 30-day readmissions, severe adverse events, and discharge to nonhome.

RESULTS

Cluster 2 was characterized by elevated preoperative BUN, creatinine, and INR and demonstrated almost twice the rate of adverse events (3.52% vs 2.20% and 2.22%), 30-day readmissions (6.39% vs 3.31% and 3.71%), and discharge to nonhome (47.97% vs 30.50% and 35.85%). Cluster 3 was characterized by a slightly higher risk of discharge to nonhome than cluster 1 and was overwhelmingly female (79.5% female, 35.8% discharge to nonhome). Cluster 1 represents the lowest-risk subgroup, experiencing the lowest rates of readmissions, adverse events, and discharge to nonhome.

CONCLUSION

Preoperative laboratory values, namely BUN, creatinine, and INR, are useful in identifying patients at risk of adverse outcomes. This analysis supports the existing surgical literature pushing for preoperative hydration as a targeted intervention to expedite recovery.

Application of a Two-Analyte Integrated Population Pharmacokinetic Model to Evaluate the Impact of Intrinsic and Extrinsic Factors on the Pharmacokinetics of Polatuzumab Vedotin in Patients with Non-Hodgkin Lymphoma

PURPOSE

The established two-analyte integrated population pharmacokinetic model was applied to assess the impact of intrinsic/extrinsic factors on the pharmacokinetics (PK) of polatuzumab vedotin (pola) in patients with non-Hodgkin lymphoma (NHL) following bodyweight-based dosing.

METHODS

Model simulations based on individual empirical Bayes estimates were used to evaluate the impact of intrinsic/extrinsic factors as patient subgroups on Cycle 6 exposures. Intrinsic factors included bodyweight, age, sex, hepatic and renal functions. Extrinsic factors included rituximab/obinutuzumab or bendamustine combination with pola and manufacturing process. The predicted impact on exposures along with the established exposure-response relationships were used to assess clinical relevance.

RESULTS

No clinically meaningful differences in Cycle 6 pola exposures were found for the following subgroups: bodyweight 100-146 kg versus 38-<100 kg, age ≥ 65 years versus <65 years, female versus male, mild hepatic impairment versus normal, mild-to-moderate renal impairment versus normal. Co-administration of rituximab/obinutuzumab or bendamustine, and change in the pola manufacturing process, also had no meaningful impact on PK.

CONCLUSIONS

In patients with NHL, bodyweight-based dosing is adequate, and no further dose adjustment is recommended for the heavier subgroup (100-146 kg). In addition, no dose adjustments are recommended for other subgroups based on intrinsic/extrinsic factors evaluated.

Low serum albumin concentration predicts the need for surgical intervention in neonates with necrotizing enterocolitis

PURPOSE

To investigate whether serum albumin (SA) concentration can predict the need for surgical intervention in neonates with necrotizing enterocolitis (NEC).

METHODS

Retrospective review of all cases with NEC Bell's stage 2 and 3 that were treated in a single center between 2009 and 2015. Data on patient demographics, clinical parameters, laboratory findings and surgical status were recorded. Receiver operating characteristics analysis was used to evaluate optimal cutoffs and predictive values.

RESULTS

Overall, 151 neonates with NEC were identified. Of these, 132 (87.4%) had confirmed NEC Bell's stage 2. The median gestational age was 28.4 (range, 23.1-39.0) weeks and 69 (52.3%) had a birth weight of ≤1000 g. Sixty-eight (51.5%) underwent surgery, showing a sustained reduction in SA over time with significantly lower median SA levels compared to 64 (48.5%) cases that responded well to medical treatment (18.3 ± 3.7 g/L vs. 26.0 ± 2.0 g/L; P < 0.001). SA concentration of ≤20 g/L on day 2 of NEC diagnosis was a significant predictor for surgery (OR 3.41; P = 0.019) with a positive predictive value of 71.4%.

CONCLUSIONS

An SA concentration of ≤20 g/L on day 2 of the NEC disease process is associated with a higher likelihood for surgical intervention in neonates with NEC Bell's stage 2. SA, in combination with other clinical parameters and serological markers, may be a useful predictive tool for surgery in NEC.

LEVEL OF EVIDENCE

II.

The Neutrophil Percentage-to-Albumin Ratio as a New Predictor of All-Cause Mortality in Patients with Cardiogenic Shock

Background

Although the neutrophil percentage-to-albumin ratio (NPAR) has proven to be a robust systemic inflammation-based predictor of mortality in a wide range of diseases, the prognostic value of the NPAR in critically ill patients with cardiogenic shock (CS) remains unknown. This study aimed at investigating the association between the admission NPAR and clinical outcomes in CS patients using real-world data.

Methods

Critically ill patients diagnosed with CS in the Medical Information Mart for Intensive Care-III (MIMIC-III) database were included in our study. The study endpoints included all-cause in-hospital, 30-day, and 365-day mortality in CS patients. First, the NPAR was analyzed as a continuous variable using restricted cubic spline Cox regression models. Second, X-tile analysis was used to calculate the optimal cut-off values for the NPAR and divide the cohort into three NPAR groups. Moreover, multivariable Cox regression analyses were used to assess the association of the NPAR groups with mortality.

Results

A total of 891 patients hospitalized with CS were enrolled in this study. A nonlinear relationship between the NPAR and in-hospital and 30-day mortality was observed (all P values for nonlinear trend<0.001). According to the optimal cut-off values by X-tile, NPARs were divided into three groups: group I (NPAR < 25.3), group II (25.3 ≤ NPAR < 34.8), and group III (34.8 ≤ NPAR). Multivariable Cox analysis showed that higher NPAR was independently associated with increased risk of in-hospital mortality (group III vs. group I: hazard ratio [HR] 2.60, 95% confidence interval [CI] 1.72-3.92, P < 0.001), 30-day mortality (group III vs. group I: HR 2.42, 95% CI 1.65-3.54, P < 0.001), and 365-day mortality (group III vs. group I: HR 6.80, 95% CI 4.10-11.26, P < 0.001) in patients with CS.

Conclusions

Admission NPAR was independently associated with in-hospital, 30-day, and 365-day mortality in critically ill patients with CS.

Modeling the transfer of low molecular weight plasma proteins during hemodialysis and online hemodiafiltration

Replacing the renal excretion of low molecular weight proteins (LMWP) by extracorporeal dialysis (dialysis) treatment poses technological challenges. Hemodialyzers with sieving coefficients for LMWP that match or even exceed those of the glomerular membrane barrier are commercially available; however, the associated losses of albumin are much higher than physiological levels of renal albumin excretion. A unidimensional, convection-diffusion model of solute transfer has been developed to analyze and quantitate LMWP extraction and albumin loss during dialysis treatment. The model is applicable to any extracorporeal dialysis technique and any type of hemodialyzer. Clinical extraction data for beta 2 microglobin (β2M, 11.6 kDa), myoglobin (16.7 kDa) and interleukin 6 (IL6, 21-30 kDa) from 15 patients on hemodiafiltration (HDF) using a Nipro Elisio H series high flux hemodialyzer were analyzed using the model and values for the convection and mass transfer coefficients were derived. The model predicts that under normal clinical operating conditions, given equal amounts of β2M removal, albumin losses are higher using pre-dilution rather than post-dilution HDF. The model can be used to provide estimates of the internal filtration rates of hemodialyzers operating in vivo.

Comprehensive two-dimensional liquid chromatography as a biomimetic screening platform for pharmacokinetic profiling of compound libraries in early drug development

A comprehensive two-dimensional liquid chromatography-based biomimetic platform (LCxLC) has been developed and validated for drug diffusion studies. Human serum albumin (HSA) and immobilized artificial membrane (IAM) were thereby used in the first (¹D) and second (²D) separation dimension, respectively. While the former was meant to emulate the blood, the latter was instead intended to mimic the intestinal mucosa epithelium. Therefore, the experimental conditions, i.e. pH, temperature and buffer composition, were modulated to reflect faithfully in vivo conditions. 30 compounds, whose effective intestinal permeability (P_eff) assayed in situ on humans by a validated technique was known from the literature, were used as model drugs. A good and orthogonal separation was achieved for the whole dataset, although for a better distribution of the most polar compounds in the elution window a segmented gradient elution program had to be employed. Interestingly, the passively uptaken compounds having the most favourable P_eff populated a specific area of the 2D plots, implying that the affinity for HSA and IAM has to lie in specific ranges in order for a compound to be satisfactorily absorbed from the intestinal lumen. Although these results should be regarded as preliminary, this work paves an entirely new and unprecedented way to profile pharmaceutically relevant compounds for their in vivo absorption and distribution potential.

Clinical characteristics and predictors of permanent stoma in rectal cancer patients underwent anterior resections: the value of preoperative prognostic nutritional index

OBJECTIVES

This study was aimed to investigate the correlation between preoperative prognostic nutritional index (PNI) and permanent stoma (PS) in patients with defunctioning stoma (DS) after anterior resections and, based on it, to reveal the clinical value of PNI on clinical strategies about the selection of stoma location.

METHODS

A total of 281 consecutive rectal cancer patients who accepted anterior resection and DS in the National Hepatobiliary and Enteric Surgery Research Center, Xiangya Hospital, Central South University from June 2008 to June 2018 were enrolled in this study. Receiver operating characteristic (ROC) curve for PNI was performed to discriminate PS. Univariate and multivariate analysis were conducted to identify the clinical characteristics and risk factors for PS. Specific reasons for patients with DS turned into PS were reviewed.

RESULTS

ROC curve analysis defined PNI cutoff level of 45.85 corresponding to PS (area under the curve (AUC) = 0.71, 77% sensitivity, 56.9% specificity). Low PNI (OR = 3.23, P = 0.005), tumor crossing the peritoneal reflection (PR) (OR = 3.42, P = 0.003), postoperative distant metastasis (OR = 6.31, P < 0.001) were independently associated with PS. Besides, anastomotic complications (31.4%), poor oncological outcomes (35.3%), and personal preferences (33.3%) were the specific reasons for patients turning into PS.

CONCLUSIONS

Preoperative PNI is an independent prognostic factor to predict PS in patients who underwent anterior resection and DS. Therefore, combined with other clinical characteristics and predictors, preoperative measurements of PNI could provide a significant support for clinical decision on patients prepared to accept anterior resection and DS.

Synthesis and characterization of photocrosslinkable albumin-based hydrogels for biomedical applications

Protein-based biomaterials are widely used to generate three-dimensional (3D) scaffolds for tissue regeneration as well as compact delivery systems for drugs, genes, and peptides. Specifically, albumin-based biomaterials are of particular interest for their ability to facilitate controlled delivery of drugs and other therapeutic agents. These hydrogels possess non-toxic and non-immunogenic properties that are desired in tissue engineering scaffolds. This work employs a rapid ultraviolet (UV) light induced crosslinking to fabricate bovine serum albumin (BSA) hydrogels. Using four different conditions, the BSA hydrogel properties were modulated based on the extent of glycidyl methacrylate modification in each polymer. The highly tunable mechanical behavior of the material was determined through compression tests which yielded a range of material strengths from 4.4 ± 1.5 to 122 ± 7.4 kPa. Pore size measurements also varied from 7.7 ± 1.7 to 23.5 ± 6.6 μm in the photocrosslinked gels. The physical properties of materials such as swelling and degradation were also characterized. In further evaluation, 3D scaffolds were used in cell encapsulation and in vivo implantation studies. The biocompatibility and degradability of the material demonstrated effective integration with the native tissue environment. These modifiable chemical and mechanical properties allow BSA hydrogels to be fine-tuned to a plethora of biomedical applications including regenerative medicine, in vitro cancer study models, and wound healing approaches.

Gender Differences in Genetic Associations of RAB38 with Urinary Protein-to-Creatinine Ratio (UPCR) Levels in Diabetic Nephropathy Patients

Renal dysfunction is common in patients with diabetes mellitus (DM). Previous findings from a meta-analysis of GWAS indicated that the variation of RAB38/CTSC is highly associated with the urinary albumin-to-creatinine ratio (UACR) in European populations. In addition, RAB38 knockout rats showed an increase in urinary albumins. Although the prevalence of chronic kidney disease is high in Taiwan, the role of genetic variants in diabetic renal function is still unclear. In the current study, 275 diabetic nephropathy (DN) patients were recruited to perform a genetic association study. Our results indicated that rs1027027, rs302647, and rs302646 in RAB38 were significantly associated with urinary protein-to-creatinine ratio (UPCR) levels in DN patients. Importantly, after analysis stratified by gender, a significant genetic influence on UPCR levels was observed in the male population. The findings confirmed the roles of gender and variants of RAB38 in the risk of UPCR in Diabetic Nephropathy patients.

Cross-species/cross-modality physiologically based pharmacokinetics for biologics: 89Zr-labelled albumin-binding domain antibody GSK3128349 in humans

Two-pore physiologically-based pharmacokinetics (PBPK) for biologics describes the tissue distribution and elimination kinetics of soluble proteins as a function of their hydrodynamic radius and the physiological properties of the organs. Whilst many studies have been performed in rodents to parameterize the PBPK framework in terms of organ-specific lymph flow rates, similar validation in humans has been limited. This is mainly due to the paucity of the tissue distribution time course data for biologics that is not distorted by target-related binding. Here, we demonstrate that a PBPK model based on rodent data provided good to satisfactory extrapolation to the tissue distribution time course of ⁸⁹Zr-labeled albumin-binding domain antibody (AlbudAb™) GSK3128349 in healthy human volunteers, including correct prediction of albumin-like plasma half-life, volume of distribution, and extravasation half-life. The AlbudAb™ used only binds albumin, and hence it also provides information about the tissue distribution kinetics and turnover of that ubiquitous and multifunctional plasma protein.

The Effect of Exercise on Nutritional Status and Body Composition in Hemodialysis: A Systematic Review

Chronic kidney disease (CKD) is associated with aggravating factors which can affect both body composition and nutritional status. The purpose of the present systematic review was to investigate the potential effects of any physical activity on body composition or nutritional status among patients with stage 5 CKD undergoing hemodialysis (HD). A literature search on PubMed, Scopus, Web of Science, Google Scholar, and Cochrane was conducted and 14 randomized clinical trials were included. Skeletal muscle index and mid-arm muscular circumference increased after resistance exercise, and the results on body mass index, % body fat, and lean body mass varied. Serum albumin and C-reactive protein, in most cases, showed a slight increase and decrease, respectively. An improvement was also observed in body strength and overall performance status. The results suggest that physical activity can be beneficial for both the body composition and nutritional status of patients undergoing HD and can help in the prevention of sarcopenia. However, further research is needed mainly in the field of nutritional status.

Intravascular albumin loss is strongly associated with plasma volume withdrawal in dialysis patients

INTRODUCTION

Low circulating albumin closely predicts mortality in end-stage renal disease (ESRD) patients. The cause(s) of hypoalbuminemia (hALB) in ESRD patients remains to be elucidated. The aim of the present study was to determine the role of plasma volume (PV) withdrawal in the reduction of total circulating albumin and essential blood solutes induced by hemodialysis (HD).

METHODS

PV determined with high-precision automated carbon monoxide-rebreathing, total circulating as well as concentration of plasma albumin and electrolytes were assessed prior to and after 4-hour HD in 10 ESRD patients.

FINDINGS

Baseline PV ranged from 3.5 to 6.2 l. After HD, PV was decreased by 689 ± 566 mL (-16%) (P = 0.004). Total circulating albumin was largely reduced after HD (170.8 ± 35.1 vs. 146.1 ± 48.9 g, P = 0.008), while albumin concentration was unaltered. According to a strong linear relationship (r = 0.91, P < 0.001), one-third of total circulating albumin is lost from the intravascular compartment for every liter of PV removed. Similar results were found regarding Na⁺ and Ca²⁺ electrolytes.

DISCUSSION

Total circulating albumin, but not albumin concentration, is substantially reduced by HD in proportion to the amount of PV removed from the circulation. This study highlights the potential contributing role of PV withdrawal to hALB in ESRD patients.

Continuous Glucose Monitoring and Use of Alternative Markers To Assess Glycemia in Chronic Kidney Disease

OBJECTIVE

In chronic kidney disease, glycated albumin and fructosamine have been postulated to be better biomarkers of glycemic control than HbA_1c. We evaluated the accuracy, variability, and covariate bias of three biomarkers (HbA_1c, glycated albumin, and fructosamine) compared with continuous glucose monitoring (CGM)-derived measurement of glycemia across estimated glomerular filtration rate (eGFR) in type 2 diabetes.

RESEARCH DESIGN AND METHODS

A prospective cohort study was conducted of 104 participants with type 2 diabetes, 80 with eGFR <60 mL/min/1.73 m² (not treated with dialysis) and 24 frequency-matched control subjects with eGFR ≥60 mL/min/1.73 m². Participants wore a blinded CGM for two 6-day periods separated by 2 weeks, with blood and urine collected at the end of each CGM period. HbA_1c, glycated albumin, and fructosamine were measured by high-performance liquid chromatographic, enzymatic, and colorimetric nitroblue tetrazolium methods, respectively.

RESULTS

Within-person biomarker values were strongly correlated between the two CGM periods (r = 0.92-0.95), although no marker fully captured the within-person variability of mean CGM glucose. All markers were similarly correlated with mean CGM glucose (r = 0.71-77). Compared with mean CGM glucose, glycated albumin and fructosamine were significantly biased by age, BMI, serum iron concentration, transferrin saturation, and albuminuria; HbA_1c was underestimated in those with albuminuria.

CONCLUSIONS

Glycated albumin and fructosamine were not less variable than HbA_1c at a given mean CGM glucose level, with several additional sources of bias. These results support measuring HbA_1c to monitor trends in glycemia among patients with eGFR <60 mL/min/1.73 m². Direct measurements of glucose are necessary to capture short-term variability.

Relation Between Globulin, Fibrinogen, and Albumin With the Presence and Severity of Coronary Artery Disease

The albumin to globulin ratio (AGR) is used as a prognostic marker in acute ischemic cardiovascular events. We investigated whether serum AGR, fibrinogen, and fibrinogen to albumin ratio (FAR) are related to the presence and severity of coronary artery disease (CAD). Patients who underwent coronary angiography procedures were analyzed retrospectively. The severity of CAD was assessed by the Gensini score. The study population (3031 patients; 1071 females and 1960 males) was divided into 3 tertiles based on AGR values. Gensini score, lipid levels, diabetes mellitus (DM), hypertension (HT), age, and fibrinogen level were higher in the low AGR group. Pearson correlation analysis showed that AGR (r = -0.068, P < .001) was negatively and fibrinogen (r = 0.187, P < .001) was positively correlated with the Gensini score. Male gender, HT, smoking, DM, age, high triglyceride (TG) level, low-density lipoprotein cholesterol (LDL-C) >160 mg/dL, estimated glomerular filtration rate (eGFR) <60 mL/min, and fibrinogen level >3.5 g/L were independent predictors of CAD. Male gender, age, eGFR, DM, LDL-C, TG, and FAR had an independent positive relation to the Gensini score. In conclusion, similar to traditional risk factors, plasma fibrinogen and albumin levels showed a close relation with the presence and severity of CAD.

Lactate/Albumin Ratio as a Predictor of In-Hospital Mortality in Septic Patients Presenting to the Emergency Department

Background: The aim of this study is to evaluate the prognostic value of the Lactate to Albumin (L/A) ratio compared to that of lactate only in predicting morbidity and mortality in sepsis patients.

Methods: This was a single-center retrospective cohort study. All adult patients above the age of 18 with a diagnosis of sepsis who presented between January 1, 2014 and June 30, 2019 were included. The primary outcome was in-hospital mortality.

Results: A total of 1,381 patients were included, 44% were female. Overall in-hospital mortality was 58.4% with the mortalities of sepsis and septic shock being 45.8 and 67%, respectively. 55.5% of patients were admitted to the intensive care unit. The area under the curve value for lactate was 0.61 (95% CI 0.57–0.65, p < 0.001) and for the L/A ratio was 0.67 (95% CI 0.63–0.70, p < 0.001). The cutoff generated was 1.22 (sensitivity 59%, specificity 62%) for the L/A ratio in all septic patients and 1.47 (sensitivity 60%, specificity 67%) in patients with septic shock. The L/A ratio was a predictor of in-hospital mortality (OR 1.53, CI 1.32–1.78, p < 0.001).

Conclusion: The L/A ratio has better prognostic performance than initial serum lactate for in-hospital mortality in adult septic patients.

SARS-CoV-2 Bound Human Serum Albumin and Systemic Septic Shock

The emergence of the COVID-19 virus and the subsequent pandemic have driven a great deal of research activity. The effects of COVID-19 are caused by the severe respiratory syndrome coronavirus 2 (SARS-CoV-2) and it is the underlying actions of SARs-CoV-2 virions on the endothelial glycocalyx that we consider here. One of the key factors in COVID-19 infection is its almost unique age-related profile, with a doubling in mortality every 10 years after the age of 50. The endothelial glycocalyx layer is essential in maintaining normal fluid homeostasis, but is fragile and prone to pathophysiological damage. It is physiologically significant in capillary microcirculation and in fluid distribution to the tissues. Human serum albumin (HSA), the most abundant protein in plasma, is created in the liver which also maintains its concentration, but this reduces by 10-15% after 50 years of age. HSA transports hormones, free fatty acids and maintains oncotic pressure, but SARS-CoV-2 virions bind competitively to HSA diminishing its normal transport function. Furthermore, hypoalbuminemia is frequently observed in patients with such conditions as diabetes, hypertension, and chronic heart failure, i.e., those most vulnerable to SARS-CoV-2 infection. Hypoalbuminemia, coagulopathy, and vascular disease have been linked in COVID-19 and have been shown to predict outcome independent of age and morbidity. Hypoalbuminemia is also known factor in sepsis and Acute respiratory distress syndrome (ARDS) occurs when fluids build-up in the alveoli and it is associated with sepsis, whose mechanism is systemic, being associated with the fluid and logistic mechanisms of the circulation. Glycocalyx damage is associated with changes plasma protein concentration, particularly HSA and blockage of albumin transport can produce the systemic symptoms seen in SARS-CoV-2 infection and sepsis. We therefore conclude that albumin binding to SARS-CoV-2 virions may inhibit the formation of the endothelial glycocalyx by inhibition of albumin transport binding sites. We postulate that albumin therapy to replace bound albumin might alleviate some of the symptoms leading to sepsis and that clinical trials to test this postulation should be initiated as a matter of urgency.

Effect of albumin administration on outcomes in hypoalbuminemic patients hospitalized with community-acquired pneumonia (ALBUCAP): a prospective, randomized, phase III clinical controlled trial-a trial protocol

Background

Community-acquired pneumonia (CAP) remains a leading cause of death worldwide, and hypoalbuminemia is associated with worse outcomes. However, it remains uncertain whether albumin administration could have any beneficial effects. We aim to assess whether the administration of albumin in hypoalbuminemic patients with CAP increases the proportion of clinically stable patients at day 5 compared with the standard of care alone.

Methods

This is a trial protocol for a superiority, non-blinded, multicenter, randomized, phase 3, interventional controlled clinical trial. The primary endpoint will be the proportion of clinical stable patients at day 5 (intention to treat), defined as those with stable vital signs for at least 24 h. The secondary endpoints will be time to clinical stability, duration of intravenous and total antibiotic treatment, length of hospital stay, intensive care unit admission, duration of mechanical ventilation and vasopressor treatment, adverse events, readmission within 30 days, and all-cause mortality. The trial has been approved by the Spanish Medicines and Healthcare Products Regulatory Agency. The investigators commit to publish the data in peer-reviewed journals within a year of the study completion date. Subjects will be recruited from three Spanish hospitals over a planned enrolment period of 2 years. A follow-up visit will be performed 1 month after discharge. We have estimated the need for a sample size of 360 patients at a two-sided 5% alpha-level with a power of 80% based on intention to treat. Eligible participants must be hospitalized, hypoalbuminemic (≤ 30 g/L), non-immunosuppressed, adults, and diagnosed with CAP. They will be randomly assigned (1:1) to receive standard care plus albumin (20 g in 100 mL) every 12 h for 4 days or standard care alone.

Discussion

If this randomized trial confirms the hypothesis, it should lead to a change in current clinical practice for the management of hypoalbuminemic patients with CAP.

Trial registration

European Clinical Trials Database (EudraCT) 2018-003117-18. Registered on 12 April 2019. ClinicalTrials.gov NCT04071041. Registered on 27 August 2019

Lymphatic targeting by albumin-hitchhiking: Applications and optimisation

The lymphatic system plays an integral role in the development and progression of a range of disease conditions, which has impelled medical researchers and clinicians to design, develop and utilize advanced lymphatic drug delivery systems. Following interstitial administration, most therapeutics and molecules are cleared from tissues via the draining blood capillaries. Macromolecules and delivery systems >20 kDa in size or 10-100 nm in diameter are, however, transported from the interstitium via draining lymphatic vessels as they are too large to cross the blood capillary endothelium. Lymphatic uptake of small molecules can be promoted by two general approaches: administration in association with synthetic macromolecular constructs, or through hitchhiking on endogenous cells or macromolecular carriers that are transported from tissues via the lymphatics. In this paper we review the latter approach where molecules are targeted to lymph by hitchhiking on endogenous albumin transport pathways after subcutaneous, intramuscular or intradermal injection. We describe the properties of the lymphatic system and albumin that are relevant to lymphatic targeting, the characteristics of drugs and delivery systems designed to hitchhike on albumin trafficking pathways and how to further optimise these properties, and finally the current applications and potential future directions for albumin-hitchhiking approaches to target the lymphatics.

Applications and pitfalls of hemoglobin A1C and alternative methods of glycemic monitoring

INTRODUCTION

Intensive glycemic control minimizes the risks of microvascular complications in diabetes. A1C is a convenient estimate of mean blood glucose, but is not the only marker available. The practical use and limitations of alternative markers and continuous glucose monitors are the focus of this review.

METHODS

PubMed and the Cochrane Library were searched for studies concerning applications or limitations of A1C, fructosamine, glycated albumin, 1,5-anhydroglucitol, skin autofluorescence, and continuous glucose monitoring. Papers reporting on strengths, limitations, or comparisons of these methods were reviewed for inclusion.

RESULTS

A1C reflects three months of glycemic control and is not an ideal marker in all patient populations. Fructosamine and glycated albumin reflect mean blood glucose over three weeks. 1,5-Anhydroglucitol can measure hyperglycemic excursions in days to weeks. Continuous glucose monitors provide immediate feedback for timely intervention to reduce glycemic excursions and can assess glycemic variability. Current barriers to continuous glucose monitor use include inexperience, cost, discomfort, and medication interference.

CONCLUSIONS

Many promising alternative glycemic markers exist. The main limitations for all alternative methods of glycemic monitoring are a lack of standardization for clinically useful cut-offs or guidelines, and a lack of long-term data on their association with complications, particularly in varied patient populations.

Hemophagocytic Lymphohistiocytosis in Patients With Primary Immunodeficiency

Hemophagocytic lymphohistiocytosis (HLH) is characterized by uncontrolled and excessive immune responses with high mortality. We aimed to define mortality-related parameters in HLH secondary to primary immunodeficiency (PID). A total of 28 patients with HLH between the years 2013 and 2017 were enrolled in the study. The patients were evaluated in 2 groups including PID with hypopigmentation (n=7) (Chédiak-Higashi syndrome [CHS] and Griscelli syndrome type 2 [GS2]) and other PIDs (n=21). The median age of the study population was 23 (4.3 to 117.0) months at the time of the diagnosis of HLH. Central nervous system involvement was recorded in 7 (GS2/CHS patients [n=4], other PIDs [n=3], P=0.026), and death was observed in 9 patients (GS2/CHS patients [n=1], other PIDs [n=8], P=0.371). Five patients (3 GS2/CHS and 2 other PID patients) underwent hematopoietic stem cell transplantation. Low serum albumin level was the only variable associated with the mortality and albumin levels less than the cut-off value of 3.07 g/dL increased mortality 5.8 times in patients with HLH secondary to PID. We presented a single-center experience consisting of patients with HLH secondary to PID with a mortality rate of 32.1%. Hypoalbuminemia was the only risk factor to increase the overall mortality rate of HLH.

Physiological role of plasma and its components and the clinical implications of different methods of apheresis: A narrative review

Nowadays, therapeutic plasmapheresis (TP) is accepted as part of the treatment for specific groups of diseases. The availability of different methods, including double filtration and adsorption, increases selectivity for the removal of substances. However, the use of these techniques requires a thorough understanding of the characteristics and components of plasma. By considering pivotal papers from several databases, the aim of this narrative review is to describe the characteristics of plasma related to apheresis techniques. We have tried to cover the clinical implications including physiology, estimation of plasma volume, viscosity, and a description of its components including the size, volume of distribution, and half-lives of the different substances to be removed or maintained depending on the clinical situation and applied apheresis technique. Applying this knowledge will help us to choose the right method and dosage and improve the efficacy of the procedure by preventing or addressing any complications.

Oral exposure of pigs to the mycotoxin deoxynivalenol does not modulate the hepatic albumin synthesis during a LPS-induced acute-phase reaction

The sensitivity of pigs to deoxynivalenol (DON) might be influenced by systemic inflammation (SI) which impacts liver. Besides following acute-phase proteins, our aim was to investigate both the hepatic fractional albumin (ALB) synthesis rate (FSR) and the ALB concentration as indicators of ALB metabolism in presence and absence of SI induced by LPS via pre- or post-hepatic venous route. Each infusion group was pre-conditioned either with a control diet (CON, 0.12 mg DON/kg diet) or with a DON-contaminated diet (DON, 4.59 mg DON/kg diet) for 4 wk. A depression of ALB FSR was observed 195 min after LPS challenge, independent of feeding group or LPS application route, which was not paralleled by a down-regulated ALB mRNA expression but by a reduced availability of free cysteine. The drop in ALB FSR only partly explained the plasma ALB concentrations which were more depressed in the DON-pre-exposed groups, suggesting that ALB levels are influenced by further mechanisms. The abundances of haptoglobin, C-reactive protein, serum amyloid A, pig major acute-phase protein, fibrinogen and LPS-binding protein mRNA were up-regulated upon LPS stimulation but not accompanied by increases in the plasma concentrations of these proteins, pointing at an imbalance between synthesis and consumption.

Use of prognostic nutritional index in the evaluation of disease activity in patients with Behçet's disease

OBJECTIVE

Behçet's disease (BD) is a chronic, multisystem disorder that can cause severe morbidity and mortality. Monitoring tools that measure disease activity are required for effective management of BD. We aimed to investigate the association of prognostic nutritional index (PNI) with disease activity in BD.

METHODS

In this cross-sectional study, we enrolled 88 adult patients with BD and 51 healthy controls. The patients were divided into patients with active and inactive BD according to their disease activities. PNI was calculated using the following formula: 10×serum albumin (g/dL)+0.005×peripheral lymphocyte count (per mm3). To evaluate BD activity, the Behçet Disease Current Activity Form was used. The relations of BD activity with PNI, neutrophil-to-lymphocyte ratio, platelet-to-lymphocyte ratio, erythrocyte sedimentation rate, and C-reactive protein were investigated. A receiver operator characteristic curve analysis was used to define the optimum cutoff value of PNI for active BD.

RESULTS

A total of 48 patients were classified as having active BD and 40 as having inactive BD. Patients with active BD had lower mean PNI than patients with inactive BD and healthy controls (51.8±4.2, 57.4±2.9, and 56.6±3.6, respectively; p<0.001). In multivariate analysis, PNI was the only independent predictor of BD activity (odds ratio, -0.687; 95% confidence interval 0.548-0.861; p=0.001). The optimum cutoff of PNI for active BD was 55.35 with 79.2% sensitivity and 77.75% specificity.

CONCLUSION

PNI was significantly associated with BD activity. PNI may be a useful tool for the assessment of disease activity in BD.

Analysis of factors affecting the prognosis of COVID-19 patients and viral shedding duration

The clinical characteristics of patients with COVID-19 were analysed to determine the factors influencing the prognosis and virus shedding time to facilitate early detection of disease progression. Logistic regression analysis was used to explore the relationships among prognosis, clinical characteristics and laboratory indexes. The predictive value of this model was assessed with receiver operating characteristic curve analysis, calibration and internal validation. The viral shedding duration was calculated using the Kaplan-Meier method, and the prognostic factors were analysed by univariate log-rank analysis and the Cox proportional hazards model. A retrospective study was carried out with patients with COVID-19 in Tianjin, China. A total of 185 patients were included, 27 (14.59%) of whom were severely ill at the time of discharge and three (1.6%) of whom died. Our findings demonstrate that patients with an advanced age, diabetes, a low PaO2/FiO2 value and delayed treatment should be carefully monitored for disease progression to reduce the incidence of severe disease. Hypoproteinaemia and the fever duration warrant special attention. Timely interventions in symptomatic patients and a time from symptom onset to treatment <4 days can shorten the duration of viral shedding.

Transfusion and Infections in the Burn Patient

Background: Blood product transfusion has historically been utilized after major burn injury in the resuscitative as well as the acute phase. Transfusion has been implicated in infection and immunosuppression in many disease states. Recommendations for blood product transfusion has varied, but several landmark studies have helped define optimal burn transfusion strategies with respect to infection. The purpose of this article is to review the evidence describing the relation between transfusion and infection in burn injury during different phases of burn treatment to identify optimal transfusion strategies and suggest future targets for transfusion research in burns. Methods: This article presents the history, current status, and future research directions related to blood and blood product transfusion in burn injury. Results: Patients with burns are subject to infectious complications resulting from the loss of skin and burn-related immunosuppression. The use of blood in burn treatment has varied during both the resuscitative phase and the acute treatment phase. Whole-blood use in resuscitation was replaced with crystalloid infusion. Future trials are examining the role of plasma and albumin in burn resuscitation. A randomized prospective multicenter transfusion trial was able to decrease transfusion by 50% with no change in infection. Further examination of the role of hemostatic resuscitation in burn excision may help to better define transfusion goals. Conclusions: Blood product transfusion in burn injury has varied throughout the last century. Although advances in the understanding of blood transfusion in burn injury have occurred, initiatives to define optimal care better are required.

Contributing factors to the plasma albumin level at diagnosis of hematological malignancy

OBJECTIVES

Many factors contribute to the plasma albumin (PA) level. We aimed to quantify different factors' relative contribution to the PA level when diagnosing hematological malignancy (HM).

METHODS

The study was a population-based registry study including patients with HM in a Danish region. We applied multivariate linear regression analyses with C-reactive protein (CRP), WHO performance score (WHO-PS), age, sex, comorbidity, and HM type as exposures and the PA level on the day of the HM diagnosis (DX) as the outcome. The relative contribution of each exposure was determined as a percentage of the models' coefficient of determination (R²).

RESULTS

In total, 2528 patients with HM had PA measured on DX. In the model comprising all exposures, CRP contributed with 65.8% to the R² of 0.389 whereas 3 variables (CRP, WHO-PS, HM type) together contributed with 96.1%. When CRP was excluded from the model, R² declined to 0.215 and the WHO-PS contributed with 96%. Other models, including separate analyses for each HM type, corroborated these results, except in myeloma patients where WHO-PS contributed with 61.1% to the R² of 0.234.

CONCLUSION

The inflammation biomarker CRP was the main predictor of the PA level on DX. The WHO-PS also contributed to the PA level on DX whereas the remaining factors (HM type, age, sex, and comorbidity) were of much less importance.

The Prognostic Value of C-reactive Protein to Albumin Ratio in Patients with Isolated Degenerative Aortic Valve Stenosis Undergoing Surgical Aortic Valve Replacement

Objective

To evaluate the prognostic value of C-reactive protein to albumin ratio (CAR) in patients with severe aortic valve stenosis undergoing surgical aortic valve replacement (AVR).

Methods

Four hundred seventy-six patients with severe degenerative aortic stenosis who underwent successful isolated surgical AVR were enrolled. Hospitalization due to heart failure, surgical aortic reoperation, paravalvular leakage rates, and long-term mortality were evaluated in the whole study group. The participants were divided into two groups, as 443 patients without mortality (group 1) and 33 patients with mortality (group 2) during the follow-up time.

Results

CAR was lower in patients without mortality than in those with mortality during the follow-up time (0.84 [0.03-23.43] vs. 2.50 [0.22-26.55], respectively, P<0.001). Age (odds ratio [OR]: 1.062, confidence interval [CI]: 1.012-1.114, P=0.014), CAR (OR: 1.221, CI: 1.125-1.325, P<0.001), ejection fraction (OR: 0.956, CI: 0.916-0.998, P=0.042), and valve type (OR: 2.634, CI: 1.045-6.638, P=0.040) were also found to be independent predictors of long-term mortality. Additionally, rehospitalization (0.86 [0.03-26.55] vs. 1.6 [0.17-24.05], P=0.006), aortic reoperation (0.87 [0.03-26.55] vs. 1.6 [0.20-23.43], P=0.016), and moderate to severe aortic paravalvular leakage (0.86 [0.03-26.55] vs. 1.86 [0.21-19.50], P=0.023) ratios were associated with higher CAR.

Conclusion

It was firstly described that CAR was strongly related with increased mortality rates in patients with isolated severe aortic stenosis after surgical AVR. Additionally, rehospitalization, risk of paravalvular leakage, and aortic reoperation rates were higher in patients with increased CAR than in those without it.

Relationship of Nutritional Status, Inflammation, and Serum Albumin Levels During Acute Illness: A Prospective Study

BACKGROUND

Low serum albumin levels resulting from inflammation-induced capillary leakage or disease-related anorexia during acute illness are associated with poor outcomes. We investigated the relationship of nutritional status and inflammation with low serum albumin levels and 30-day mortality in a large cohort.

METHODS

We prospectively enrolled adult patients in the medical emergency department of a Swiss tertiary care center and investigated associations of C-reactive protein (CRP) and Nutritional Risk Screening 2002 as markers of inflammation and poor nutritional status, respectively, with low serum albumin levels and mortality using multivariate regression analyses.

RESULTS

Among the 2465 patients, 1019 (41%) had low serum albumin levels (<34 g/L), 619 (25.1%) had increased nutritional risk (Nutritional Risk Screening 2002 ≥3), and 1086 (44.1%) had CRP values >20 mg/L. Multivariate analyses adjusted for age, gender, diagnosis, and comorbidities revealed elevated CRP values (adjusted odds ratio [OR] 10.51, 95% confidence interval, 7.51-14.72, P <.001) and increased malnutrition risk (adjusted OR 2.87, 95% confidence interval, 1.98-4.15, P <.001) to be associated with low serum albumin levels, even adjusting for both parameters. Low serum albumin levels, elevated CRP values, and increased nutritional risk independently predicted 30-day mortality, with areas under the curve of 0.77, 0.70, and 0.75, respectively. Combination of these 3 parameters showed an area under the curve of 0.82 to predict mortality.

CONCLUSIONS

Elevated parameters of inflammation and high nutritional risk were independently associated with hypoalbuminemia. All 3 parameters independently predicted mortality. Combining them during initial evaluation of patients in emergency departments facilitates mortality risk stratification.

High-protein compared with standard parenteral nutrition in palliative cancer care

Objectives

High-protein parenteral nutrition (PN) has been developed to counteract muscle loss in patients with cancer treated with PN. Nevertheless, it is not clear if high-protein PN is as safe as standard PN in patients with palliative cancer. Our primary aim was to compare the proportion of patients with elevated liver enzymes between high-protein and standard PN in patients with palliative cancer enrolled to Medical Home Care. Our secondary aim was to compare the two treatments with regard to weight and albumin levels during treatment.

Methods

Medical records from 2016 to 2018 were retrospectively reviewed to identify palliative cancer patients that had received PN for more than 3 weeks. Data on weight, height, albumin, liver enzymes, socioeconomic factors and dietitian consultations were collected at baseline and after 3–8 weeks of PN treatment. The odds of having elevated liver enzymes or having a maintained weight and/or stable albumin levels were calculated using logistic regression.

Results

20 patients treated with high-protein PN were compared with 104 patients treated with standard PN. Patients treated with high-protein PN had a significantly higher weight at follow-up compared with patients treated with standard PN (p<0.05). There was no significant difference in the proportion of patients with elevated liver enzymes (OR 0.20; 95% CI 0.02 to 1.86), or maintained weight and/or albumin levels (OR 1.62; 95% CI 0.46 to 5.76) between high-protein and standard PN.

Conclusion

High-protein PN was as safe, and at least as effective, as standard PN to patients with palliative cancer.

Acute and Subchronic Oral Toxicity of Oil Palm Puree in Sprague–Dawley Rats

Palm puree is rich in antioxidants and is produced via blending various proportions of mesocarp fibre and crude palm oil. The aim of this study was to assess the acute and subchronic toxicity of palm puree in male and female Sprague–Dawley rats. For the acute toxicity study, animals administered single palm-puree doses (2000 mg kg−1) by gavage were observed daily for 14 d. For the subchronic toxicity study, the rats were administered 500, 1000, or 2000 mg kg−1 palm puree daily for 28 d. We evaluated body and organ weights; performed haematological, biochemical, and histopathological analyses of blood and organ samples during and after treatment; and calculated the oral no-observed-adverse-effect level (NOAEL). The toxicity studies showed no signs of toxicity or mortality. The haematological, biochemical, and histopathological analyses and body and organ weights indicated no evidence of substantial toxicity at any dose of palm puree. The oral lethal dose and NOAEL for the palm puree were greater than 2000 mg kg−1 d−1 over 28 d. To the best of our knowledge, the present study is the first to confirm the safety of palm puree as a novel functional food. These encouraging results warrant further studies to elucidate its potential for pharmaceutical formulations.

Acute and Subchronic Oral Toxicity of Oil Palm Puree in Sprague-Dawley Rats

Palm puree is rich in antioxidants and is produced via blending various proportions of mesocarp fibre and crude palm oil. The aim of this study was to assess the acute and subchronic toxicity of palm puree in male and female Sprague–Dawley rats. For the acute toxicity study, animals administered single palm-puree doses (2000 mg kg⁻¹) by gavage were observed daily for 14 d. For the subchronic toxicity study, the rats were administered 500, 1000, or 2000 mg kg⁻¹ palm puree daily for 28 d. We evaluated body and organ weights; performed haematological, biochemical, and histopathological analyses of blood and organ samples during and after treatment; and calculated the oral no-observed-adverse-effect level (NOAEL). The toxicity studies showed no signs of toxicity or mortality. The haematological, biochemical, and histopathological analyses and body and organ weights indicated no evidence of substantial toxicity at any dose of palm puree. The oral lethal dose and NOAEL for the palm puree were greater than 2000 mg kg⁻¹ d⁻¹ over 28 d. To the best of our knowledge, the present study is the first to confirm the safety of palm puree as a novel functional food. These encouraging results warrant further studies to elucidate its potential for pharmaceutical formulations.

Protein-losing enteropathy

PURPOSE OF REVIEW

The present review offers its readers a practical overview of protein-losing enteropathy, particularly with regard to diagnostic and therapeutic approaches. The aim is to support clinicians in their daily practice with a practical tool to deal with protein-losing enteropathy.

RECENT FINDINGS

The literature covering protein-losing enteropathy does not appear to be quite recent and also guidelines are scanty. The main innovations during the last decade probably regard the introduction of enteroscopic techniques in the diagnostic flowchart. The use of video-capsule and device-assisted enteroscopy has enabled the direct exploration of the small bowel and the identification of the damage causing the loss of proteins from the gastrointestinal tract. Other innovations are to do with the therapies of the disorder underlying protein-losing enteropathy, although the support with nutritional supplementation are the direct remedies to tackle the protein loss.

SUMMARY

Protein-losing enteropathy represents an important clinical aspect of different gastrointestinal and extra-intestinal diseases. An established flowchart is still unavailable, but the use of enteroscopy has deeply changed the modern diagnostic approach. Nutritional support and therapy of the underlying disease are pivotal to patients' management.

Human Serum Albumin Labelled with Sterically-Hindered Nitroxides as Potential MRI Contrast Agents

Four albumin-nitroxide conjugates were prepared and tested as metal-free organic radical contrast agents (ORCAs) for magnetic resonance imaging (MRI). Each human serum albumin (HSA) carrier bears multiple nitroxides conjugated via homocysteine thiolactones. These molecular conjugates retain important physical and biological properties of their HSA component, and the resistance of their nitroxide groups to bioreduction was retained or enhanced. The relaxivities are similar for these four conjugates and are much greater than those of their individual components: the HSA or the small nitroxide molecules. This new family of conjugates has excellent prospects for optimization as ORCAs.

Tissue sodium concentrations in chronic kidney disease and dialysis patients by lower leg sodium-23 magnetic resonance imaging

BACKGROUND

Sodium-23 magnetic resonance imaging (23Na MRI) allows direct measurement of tissue sodium concentrations. Current knowledge of skin, muscle and bone sodium concentrations in chronic kidney disease (CKD) and renal replacement therapy patients is limited. In this study we measured the tissue sodium concentrations in CKD, hemodialysis (HD) and peritoneal dialysis (PD) patients with 23Na MRI of the lower leg and explored their correlations with established clinical biomarkers.

METHODS

Ten healthy controls, 12 CKD Stages 3-5, 13 HD and 10 PD patients underwent proton and 23Na MRI of the leg. The skin, soleus and tibia were segmented manually and tissue sodium concentrations were measured. Plasma and serum samples were collected from each subject and analyzed for routine clinical biomarkers. Tissue sodium concentrations were compared between groups and correlations with blood-based biomarkers were explored.

RESULTS

Tissue sodium concentrations in the skin, soleus and tibia were higher in HD and PD patients compared with controls. Serum albumin showed a strong, negative correlation with soleus sodium concentrations in HD patients (r = -0.81, P < 0.01). Estimated glomerular filtration rate showed a negative correlation with tissue sodium concentrations (soleus: r = -0.58, P < 0.01; tibia: r = -0.53, P = 0.01) in merged control-CKD patients. Hemoglobin was negatively correlated with tissue sodium concentrations in CKD (soleus: r = -0.65, P = 0.02; tibia: r = -0.73, P < 0.01) and HD (skin: r = -0.60, P = 0.04; tibia: r = -0.76, P < 0.01).

CONCLUSION

Tissue sodium concentrations, measured by 23Na MRI, increase in HD and PD patients and may be associated with adverse metabolic effects in CKD and dialysis.

C-reactive protein and albumin kinetics after antibiotic therapy in community-acquired bloodstream infection

OBJECTIVES

We assessed C-reactive protein (CRP) and plasma albumin (PA) kinetics to evaluate community-acquired bloodstream infection (CA-BSI) patients' 1-year outcomes.

METHODS

Population-based study, with CRP and PA measurements on day 1 (D1) and D4. Relative CRP variations in relation to D1 CRP value were evaluated (CRP-ratio). Patients were classified as fast response, slow response, non-response, and biphasic response.

RESULTS

A total of 935 patients were included. At D4, the CRP-ratio was lower in survivors on D365 in comparison with D4-D30 non-survivors and D30-D365 non-survivors (p<0.001). In comparison with fast response patients, non-response and biphasic response patients had 2.74 and 5.29 increased risk, respectively, of death in D4-D30 and 2.77 and 3.16 increased risk, respectively, of death in D31-D365. PA levels remained roughly unchanged from D1-D4, but lower D1 PA predicted higher short and long-term mortality (p<0.001). The discriminative performance of the CRP-ratio and D1 PA to identify patients with poor short and long-term mortality after adjustments was acceptable (AUROC=0.79).

CONCLUSIONS

Serial CRP measurements at D1 and D4 after CA-BSI is clinically useful to identify patients with poor outcome. Individual patterns of CRP-ratio response with PA at D1 further refine our ability of predicting short or long-term mortality.

Longitudinal trajectory patterns of plasma albumin and C-reactive protein levels around diagnosis, relapse, bacteraemia, and death of acute myeloid leukaemia patients

Background

No study has evaluated C-reactive protein (CRP) and plasma albumin (PA) levels longitudinally in patients with acute myeloid leukaemia (AML).

Methods

We studied defined events in 818 adult patients with AML in relation to 60,209 CRP and PA measures. We investigated correlations between CRP and PA levels and daily CRP and PA levels in relation to AML diagnosis, AML relapse, or bacteraemia (all ±30 days), and death (─30–0 days).

Results

On the AML diagnosis date (D0), CRP levels increased with higher WHO performance score (PS), e.g. patients with PS 3/4 had 68.1 mg/L higher CRP compared to patients with PS 0, adjusted for relevant covariates. On D0, the PA level declined with increasing PS, e.g. PS 3/4 had 7.54 g/L lower adjusted PA compared to PS 0. CRP and PA levels were inversely correlated for the PA interval 25–55 g/L (R = − 0.51, p < 10–5), but not for ≤24 g/L (R = 0.01, p = 0.57). CRP increases and PA decreases were seen prior to bacteraemia and death, whereas no changes occurred up to AML diagnosis or relapse. CRP increases and PA decreases were also found frequently in individuals, unrelated to a pre-specified event.

Conclusions

PA decrease is an important biomarker for imminent bacteraemia in adult patients with AML.

Hypoalbuminemia as a marker of protein metabolism disarrangement in patients with stable chronic heart failure

BACKGROUND

Despite therapeutic advances, chronic heart failure (CHF)-related mortality and hospitalization is still unacceptably high. Evidence shows that muscular wasting, sarcopenia, cachexia are independent predictors of mortality and morbidity in CHF and are signs of protein metabolism disarrangement (PMD), which involve all body proteins including circulating one. We postulate that circulating human serum albumin (HSA) could be a marker of PMD and catabolic low-grade inflammation (LGI) in CHF patients.

METHODS

One hundred sixty-six stable CHF patients (73% males), with optimized therapy referred to cardiac rehabilitation, were retrospectively divided into three groups based on their HSA concentration: ≥3.5 g/dL (normal value), 3.2-3.49 g/dL (low value); ≤3.19 g/dL (severe value). Hematochemical analyses (including circulating proteins and inflammatory markers) and body mass composition (by Bioelectrical Impedance Vector Analysis) were collected and compared. Correlations and multivariate regression were performed.

RESULTS

Despite being overweight (BMI=27 kg/m2), 75% of patients had reduced HSA (<3.5 g/dL) with suspectable sarcopenia, and 35% of all patients had remarkably lower albumin concentrations (<3.19 g/dL). Hypoalbuminemic patients were disable, older, with reduced muscular proteins, bilirubin and hemoglobin, increased extracellular water and LGI (P<0.01). HSA correlated with all of these parameters (all: P<0.01). Age, LGI, BMI, free-fat Mass, and bilirubin were independent predictors of HSA concentration. All these findings were male-dependent.

CONCLUSIONS

HSA could be considered a simple marker of PMD and LGI in CHF patients. Evaluation of PMD and gender differences should be considered in new CHF clinical trials.

Amoxicillin Inactivation by Thiol-Catalyzed Cyclization Reduces Protein Haptenation and Antibacterial Potency

Serum and cellular proteins are targets for the formation of adducts with the β-lactam antibiotic amoxicillin. This process could be important for the development of adverse, and in particular, allergic reactions to this antibiotic. In studies exploring protein haptenation by amoxicillin, we observed that reducing agents influenced the extent of amoxicillin-protein adducts formation. Consequently, we show that several thiol-containing compounds, including dithiothreitol, N-acetyl-L-cysteine, and glutathione, perform a nucleophilic attack on the amoxicillin molecule that is followed by an internal rearrangement leading to amoxicillin diketopiperazine, a known amoxicillin metabolite with residual activity. Increased diketopiperazine conversion is also observed with human serum albumin but not with L-cysteine, which mainly forms the amoxicilloyl amide. The effect of thiols is catalytic and can render complete amoxicillin conversion. Interestingly, this process is dependent on the presence of an amino group in the antibiotic lateral chain, as in amoxicillin and ampicillin. Furthermore, it does not occur for other β-lactam antibiotics, including cefaclor or benzylpenicillin. Biological consequences of thiol-mediated amoxicillin transformation are exemplified by a reduced bacteriostatic action and a lower capacity of thiol-treated amoxicillin to form protein adducts. Finally, modulation of the intracellular redox status through inhibition of glutathione synthesis influenced the extent of amoxicillin adduct formation with cellular proteins. These results open novel perspectives for the understanding of amoxicillin metabolism and actions, including the formation of adducts involved in allergic reactions.

Screening of multiple hemoprotein-specific aptamers and their applications for the binding, quantification, and extraction of hemoproteins in a microfluidic system

The blood hemoproteins, albumin, γ-globulin, and fibrinogen, serve as biomarkers for a variety of human diseases, including kidney and hepatorenal syndromes. Therefore, there is a need to quickly and accurately measure their concentrations in blood. Herein, nucleic acid aptamers demonstrating high affinity and specificity toward these hemoproteins were selected via systematic evolution of ligands by exponential enrichment, and their ability to capture their protein targets was assessed with sodium dodecyl sulfate-polyacrylamide gel electrophoresis followed by a tetramethyl benzidine assay. The limits of detection for the hemoproteins were all around 10-3 μM, and dissociation constant values of 131, 639, and 29nM were obtained; capture rates were measured to be 66%, 71%, and 61%, which is likely to be suitable for clinical diagnostics. Furthermore, a multi-layer microfluidic disk system featuring hemoprotein-specific aptamers for depleting hemoproteins was demonstrated. It could be a promising approach to use aptamers to replace conventional antibodies.

Ameliorative activity of Adansonia digitata fruit on high sugar/high fat diet-simulated Metabolic Syndrome model in male Wistar rats

Metabolic syndrome is a complex of metabolic disorders characterized by oxidative stress which compromises cell functions and entails multiple organs pathologies. We investigated the therapeutic and protective potential of Adansonia digitata fruit -a potent antioxidant- in high sugar/high fat diet-simulated metabolic syndrome in Wistar rats. 42 male rats (140-200 g) were randomly divided into 7 groups. G1 was kept on standard laboratory diet (SLD) for all 9 weeks (negative control). 5 groups were fed high Sugar/high fat diet for 6 weeks then switched to SLD for another 3 weeks + oral treatment as follows: G2+ no treatment (positive control), G3-G5 + 200, 400 and 800 mg/kg/day aqueous A. digitata fruit respectively, G6 + 10 mg/kg/day Simvastatin. G7 + HS/HFD + 400 mg/kg/day A. digitata fruit simultaneously and was terminated at W6. Our results showed that G2-G6 develops dyslipidemia, hyperglycaemia, weight gain, elevated hepatic biomarkers, elevated creatinine and urea plus pathological derangements in the heart, liver and kidney tissues compared to negative control at W6. 200 mg/kg/day A. digitata fruit significantly ameliorated the induced dyslipidemia (P ≤ 0.001), hyperglycaemia (P ≤ 0.001) with a significant reduction in the Atherogenic Index of Plasma (P ≤ 0.000) after 3 weeks treatment. The fruit normalized the elevated hepatic biomarkers as well as creatinine and urea. A dose dependent partial reduction in lesion intensity was observed in the hepatic tissue while the heart and kidney showed mostly reversed to normal histology. The inflammatory infiltration was eliminated. Relevant results were observed for the two higher doses. The simultaneous treatment showed significant lower levels in all biomarkers investigated compared to positive control which could be interpreted as protective activity. A reduction of 4-11% in whole body weight was achieved. CONCLUSION: MetS was successfully simulated with a HS/HFD formula in male Wistar rats. Treatment with aqueous A. digitata fruit showed anti-Metabolic Syndrome potential reflected by weight loss, anti-inflammatory, hypolipidemic, hypoglycaemic, renal, hepatic and cardio-protective activities.