Preoperative Serum Albumin Levels and Postoperative Acute Kidney Injury in Off-Pump Coronary Artery Bypass Surgery: A Single-Center Study in Bangladesh

Background: Serum albumin, a vital plasma protein, helps maintain intravascular colloidal osmotic pressure, cardiac output, and renal function. Low preoperative serum albumin is linked to poor outcomes, including acute kidney injury (AKI), after off-pump coronary artery bypass (OPCAB) surgery. This study aimed to assess the relationship between preoperative serum albumin levels and early postoperative renal injury. Methods: This prospective comparative cross-sectional study was conducted from August 2019 to February 2021 at the National Heart Foundation Hospital & Research Institute, Bangladesh. It included 160 adult patients with normal preoperative renal function undergoing OPCAB. Patients were divided into two groups: Group A (serum albumin ≥ 4.0 gm/dl) and Group B (serum albumin Results: Preoperative serum albumin was significantly different between groups (Group A: 4.21 ± 0.05 gm/dl, Group B: 3.69 ± 0.04 gm/dl, p = 0.028). Group B had a higher incidence of hypertension (71.25% vs. 51.25%, p st and 3rd postoperative days were higher in Group B (p th day. Postoperative AKI occurred in 18.75% of Group A and 36.25% of Group B. Multivariate regression indicated that low preoperative serum albumin is an independent risk factor for postoperative AKI (p = 0.012, OR = 1.815, CI: 0.675 - 1.162). Conclusion: Preoperative serum albumin level is a valuable predictor of postoperative renal function. Ensuring high normal serum albumin levels before surgery can help minimize the risk of postoperative AKI.

Association between serum albumin levels and disease severity in adult patients with dengue: A 7-year retrospective cohort study in China's Mainland

Objective:To identify the association between serum albumin levels and disease severity among adult patients with dengue in China's Mainland.Methods:This retrospective cohort study analyzed the data of adult patients(aged≥18 years)hospitalized with laboratory-confirmed dengue in a tertiary center for infectious diseases from 2013 to 2019 in China's Mainland.Serum albumin levels were estimated and compared between patients with severe dengue and non-severe dengue.Additionally,the association between serum albumin levels and severe dengue was evaluated using a generalized linear model[relative risks(RR)].Multivariate logistic regression analysis was performed to identify the potential predictors of severe dengue.Results:Overall,1568 patients were included in this study.Of these patients,34(2.17%)developed severe dengue.The median serum albumin levels were significantly lower in patients with severe dengue than that in those with non-severe dengue(33 g/L vs.37 g/L,P<0.001).After adjustment for age,sex,and comorbidities,hypoalbuminemia(RR 4.877,95%CI 2.193-11.461,P<0.001)was found to be a predictor of severe dengue.Serum albumin levels(OR 1.303,95%CI 1.161-1.462,P<0.001)and age(OR 1.038,95%CI 1.017-1.061,P<0.001)were significant risk factors for severe dengue.The area under the curve for serum albumin levels to distinguish severe dengue was 0.787.Conclusions:Lower serum albumin levels were significantly associated with disease severity in adult patients with dengue.Hypoalbuminemia on admission resulted in at least a four-fold increased risk of severe dengue.

Correlation of serum albumin level on postoperative day 2 with hospital length of stay in patients undergoing emergency surgery for perforated peptic ulcer

BACKGROUND Perforated peptic ulcer(PPU)is a common emergency surgical condition and a significant cause of morbidity and mortality worldwide.While advances in surgical techniques have improved outcomes for patients with PPU,many factors still affect postoperative hospital stay and overall prognosis.One potential factor is the serum albumin(SA)level,a widely utilized marker of nutritional status that has been associated with length of stay and complications in various surgical procedures.AIM To clarify the correlation of SA level on postoperative day 2 with hospital length of stay(HLOS)in patients undergoing emergency surgery for perforated peptic ulcer(PPU).METHODS We retrospectively collected and analyzed clinical baseline data,including blood routine and SA levels,of patients who underwent emergency PPU surgery and postoperative treatment at the Lingnan Hospital,the Third Affiliated Hospital of Sun Yat-sen University between December 2012 and September 2021.Patients were grouped according to HLOS with 7 d as the cut-off value,and relevant indicators were analyzed using SPSS 26.0.RESULTS Of the 37 patients undergoing emergency surgery for PPU referred to our department,33 had gastric and 4 had duodenal ulcer perforation.The median HLOS was 10 d.There were 8 patients in the≤7-d group(median HLOS:7 d)and 29 patients in the>7-d group(median HLOS:10 d).The≤7-d group had markedly higher SA on postoperative day 2 than the>7-d group(37.7 g/L vs 32.6g/L;P<0.05).The SA level on postoperative day 2 was a protective factor for patients with HLOS>7 d(Odds ratio=0.629,P=0.015).The cut-off of SA on postoperative day 2 was 30.6g/L,with an area under the curve of 0.86 and a negative predictive value of 100%for the prediction of HLOS≤7 d.CONCLUSION The SA level on postoperative day 2 was associated with the HLOS in patients undergoing emergency surgery for PPU.The pre-and post-operative albumin levels should be monitored,and infusion of human SA should be considered in a timely manner.

Serum albumin as a prognostic predictor reflecting host immunity in patients with non-small cell lung cancer

Objective:Serum albumin(ALB)can transport nutrients to circulating and local immune cells by passing through blood vessels and has attracted attention as a prognostic predictor of non-small cell lung cancer(NSCLC)because it reflects the host immunity from peripheral blood(PBL)to the tumor microenvironment. Methods:Clinical data regarding the PBL and tumor tissues were obtained at The First Hospital of Jilin University between February 2009 and March 2017.We detected indices of glucose and lipid metabolism,classified and counted PBL lymphocytes using flow cy-tometry,determined the tumor-infiltrating lymphocytes by quantitative immunofluorescence,and analyzed the T-cell receptor(TCR)rep-ertoire by high-throughput sequencing of the TCR β-chain.The correlations between ALB and metabolic immune indices were analyzed by t tests and Pearson chi-square test. Results:A total of 211 enrolled NSCLC patients were divided into a relatively high-ALB group(>41.75 g/L,n = 56)and a low-ALB group(≤41.75 g/L,n = 155);patients with high ALB had lower Treg cells(P<0.05)and more CD8+ cytotoxic T cells in the PBL(P<0.01)and a higher proportion of stromal CD8+ tumor-infiltrating lymphocytes(P = 0.047)than patients with low ALB.High ALB was also significantly related to more diversity in the TCR repertoire(P = 0.0021,r2 = 0.5481).Moreover,ALB was identified as an in-dependent prognostic factor based on a multivariate Cox regression analysis(P = 0.032;hazard ratio(HR)= 1.804;95%confidence interval(CI)= 1.035-3.146).The median overall survival in patients with low ALB vs high ALB was 28.2 vs 42.2 months(P=0.0142),respectively.Among patients with nonmetastatic NSCLC(stage Ⅰ-Ⅲ),there was a higher incidence of distant metastasis in the low-ALB group than that in the high-ALB group(41.3%and 22.2%,P=0.043).A low ALB also had a strong association with a higher risk for disease progression(P<0.001)and death(P<0.01;HR = 0.555;95%CI= 0.312-0.988). Conclusions:Albumin could affect the host immunity,and high ALB predicted a reduced risk of distant metastasis and improved the prognosis in NSCLC patients.

Study on the secondary structure and hydration effect of human serum albumin under acidic pH and ethanol perturbation with IR/NIR spectroscopy

Human serum albumin(HSA)is the most abundant protein in plasma and plays an essential physiological role in the human body.Ethanol precipitation is the most widely used way to obtain HSA,and pH and ethanol are crucial factors affecting the process.In this study,infrared(IR)spectroscopy and near-infrared(NIR)spectroscopy in combination with chemometrics were used to investigate the changes in the secondary structure and hydration of HSA at acidic pH(5.6-3.2)and isoelectric pH when ethanol concentration was varied from 0%to 40%as a perturbation.IR spectroscopy combined with the two-dimensional correlation spectroscopy(2DCOS)analysis for acid pH system proved that the secondary structure of HSA changed significantly when pH was around 4.5.What's more,the IR spectroscopy and 2DCOS analysis showed different secondary structure forms under different ethanol concentrations at the isoelectric pH.For the hydration effect analysis,NIR spectroscopy combined with the McCabe-Fisher method and aquaphotomics showed that the free hydrogen-bonded water fluctuates dynamically,with ethanol at 0-20%enhancing the hydrogen-bonded water clusters,while weak hydrogen-bonded water clusters were formed when the ethanol concentration increased continuously from 20%to 30%.These measurements provide new insights into the structural changes and changes in the hydration behavior of HSA,revealing the dynamic process of protein purification,and providing a theoretical basis for the selection of HSA alcoholic precipitation process parameters,as well as for further studies of complex biological systems.

Studies on Interactions of Antibiotics with Serum Albumin by Surface Plasmon Resonance Biosensor

Characterizing how chemical compounds binding to serum albumin is essential in evaluating drug candidates and is the focus of this study. A surface plasmon resonance biosenser developed in this laboratory was used to determine the binding constants of antibiotics with serum albumin. The binding constants of five antibiotics（asithromycin, spectinomycin, gentamycin, metacycline and kanamycin） with serum albumins were obtained.

Interaction Between Gatifloxacin and Bovine Serum Albumin

Aim To study the reaction mechanism between gatifloxacin and bovine serumalbumin (BSA) at different pHs. Methods Fluorescence spectra and UV absorbance spectra were used.Results The binding constants were determined from a double reciprocal Lineweaver-Burk curves atdifferent pHs. The binding distance r under normal physiological condition was obtained according toFoster theory of non-radiative energy transfer. The binding force between gatifloxacin and BSA wasinferred by thermody-namical coordination. Conclusion The interaction between gatifloxacin and BSAseems to be strong and the main binding force is electrostatic force.

(E)-2-Benzylidenecycloalkanones XII.*Kinetic Measurement of Bovine and Human Serum Albumine Interaction with Selected Chalcones and Their Cyclic Chalcone Analogues by UV Spectrophotometry

UV-VIS spectroscopic investigations of interaction of bovine and human serum albumin with selected chalcones (1) and their cyclic chalcone analogues: (E)-2-(4’-X-benzylidene-1-tetralones (3), benzosuberones (4) with dimethylamino and methoxy substituents and (E)-2-(2’,4’-dimethox- ybenzylidene)-1-indanone (2) were performed in polar respiration medium. Absorption maxima of the tested compounds were investigated in the presence of bovine and human serum albumin at the 0, 10, 30 and 60 minute timepoints of the interaction. The absorbance of all studied compounds in the presence of proteins decreased after one hour of the reaction. Molecule 4a showed the strongest and fastest kinet initial interaction with both albumins.

Postoperative decrease of serum albumin predicts shortterm complications in patients undergoing gastric cancer resection

AIM To find an accurate and simple predictor for postoperative short-term complications after gastrectomy. METHODS Two hundred and twenty-three patients undergoing gastric cancer resection between October 1,2015 and September 30,2016 were enrolled in this study. Univariate and multivariate analyses were used toidentify risk factors for complications after gastrectomy. The cutoff values and diagnostic accuracy were examined by receiver operating characteristic curves.RESULTS Sixty-two(27.8%) patients had short-term complications after gastric cancer resection. The postoperative decrease in serum albumin(?ALB) was an independent risk factor for complications(OR = 17.957,95%CI: 6.073-53.095,P < 0.001). The cutoff value was 14.0% and the area under the curve was higher than that of C-reactive protein on postoperative day 3(area under the curve: 0.806 vs 0.709). Patients with ?ALB ≥ 14.0% were more likely to have short-term complications after gastrectomy(46.7% vs 5.0%,P < 0.001),prolonged hospital stay(17.2 ± 10.8 d vs 14.1 ± 4.2 d,P = 0.007) and higher comprehensive complication index(P < 0.001) than those with ?ALB < 14.0%.CONCLUSION Postoperative ?ALB with a cutoff of 14.0% can be used to recognize patients who have high risk of short-term complications following gastric cancer resection.

Spectroscopic analysis on the binding interaction of biologically active pyrimidine derivative with bovine serum albumin

A biologically active antibacterial reagent, 2-amino-6-hydroxy-4-（4-N, N-dimethylaminophenyl）-pyr- imidine-5-carbonitrile （AHDMAPPC）, was synthesized. It was employed to investigate the binding in- teraction with the bovine serum albumin （BSA） in detail using different spectroscopic methods. It ex- hibited antibacterial activity against Escherichia cali and Staphylococcus aureus which are common food poisoning bacteria. The experimental results showed that the fluorescence quenching of model carrier protein BSA by AHDMAPPC was due to static quenching. The site binding constants and number of binding sites （n ≈ 1） were determined at three different temperatures based on fluorescence quenching results. The thermodynamic parameters, enthalpy change （AH）, free energy （AG） and entropy change （AS） for the reaction were calculated to be 15.15 kJ/mol, -36.11 kJ/mol and 51.26J/mol K according to van＇t Hoff equation, respectively. The results indicated that the reaction was an endothermic and spontaneous process, and hydrophobic interactions played a major role in the binding between drug and BSA. The distance between donor and acceptor is 2.79 nm according to Forster＇s theory. The alterations of the BSA secondary structure in the presence of AHDMAPPC were confirmed by UV-visible, synchronous fluorescence, circular dichroism （CD） and three-dimensional fluorescence spectra. All these results in- dicated that AHDMAPPC can bind to BSA and be effectively transported and eliminated in the body. It can be a useful guideline for further drug design.

Significance of functional hepatic resection rate calculated using 3D CT/^(99m)Tc-galactosyl human serum albumin singlephoton emission computed tomography fusion imaging

AIM: To evaluate the usefulness of the functional hepatic resection rate (FHRR) calculated using 3D computed tomography (CT)/99mTc-galactosyl-human serum albumin (GSA) single-photon emission computed tomography (SPECT) fusion imaging for surgical decision making.METHODS: We enrolled 57 patients who underwent bi- or trisectionectomy at our institution between October 2013 and March 2015. Of these, 26 patients presented with hepatocellular carcinoma, 12 with hilar cholangiocarcinoma, six with intrahepatic cholangiocarcinoma, four with liver metastasis, and nine with other diseases. All patients preoperatively underwent three-phase dynamic multidetector CT and 99mTc-GSA scintigraphy. We compared the parenchymal hepatic resection rate (PHRR) with the FHRR, which was defined as the resection volume counts per total liver volume counts on 3D CT/99mTc-GSA SPECT fusion images.RESULTS: In total, 50 patients underwent bisectionectomy and seven underwent trisectionectomy. Biliary reconstruction was performed in 15 patients, including hepatopancreatoduodenectomy in two. FHRR and PHRR were 38.6 ± 19.9 and 44.5 ± 16.0, respectively; FHRR was strongly correlated with PHRR. The regression coefficient for FHRR on PHRR was 1.16 (P < 0.0001). The ratio of FHRR to PHRR for patients with preoperative therapies (transcatheter arterial chemoembolization, radiation, radiofrequency ablation, etc.), large tumors with a volume of > 1000 mL, and/or macroscopic vascular invasion was significantly smaller than that for patients without these factors (0.73 ± 0.19 vs 0.82 ± 0.18, P < 0.05). Postoperative hyperbilirubinemia was observed in six patients. Major morbidities (Clavien-Dindo grade ≥ 3) occurred in 17 patients (29.8%). There was no case of surgery-related death.CONCLUSION: Our results suggest that FHRR is an important deciding factor for major hepatectomy, because FHRR and PHRR may be discrepant owing to insufficient hepatic inflow and congestion in patients with preoperative therapies, macroscopic vascular invasion, and/or a tumor volume of > 1000 mL.

Investigation of the binding behavior of human serum albumin and phosphorothioate oligodeoxynucleotide

Aim To study the binding behavior between human serum albumin （HSA） and phosphorothioate oligodeoxynucleotide （PS- ODN） and the effects of bivalent cations on the interaction. Methods Surface plasma resonance, circular dichroism and fluorescence experiments were conducted. Results （ 1 ） the binding ability was decreased along with the increase of pH; （2） Zn^2＋and Ni^2＋ enhanced the interaction between PS-ODN and HSA; （3） Upon PS-ODN binding, the conformation of HSA was changed with an increase of β - sheet. Conclusion The results provide experimental evidences to the hypothesis that PS-ODN binds with HSA in the positive potential region, and histidine residues located in the region play a crucial rule in the interaction.

Combined fluorescence and electrochemical investigation on the binding interaction between organic acid and human serum albumin

Human serum albumin （HSA） is a plasma protein responsible for the binding and transport of fatty acids and a variety of exogenous chemicals such as drugs and environmental pollutants. Such binding plays a crucial role in determining the ADME （absorption, distribution, metabolism, and excretion） and bioavailability of the pollutants. The binding interaction between HSA and acetic acid （C2）, octanoic acid （C8） and dodecanoic acid （C12） has been investigated by the combination of site-specific fluorescent probe, tryptophan intrinsic fluorescence and tyrosine electrochemistry. For the study of the fatty acid interaction with the two drug-binding sites on HSA, two fluorescent probes, dansylamide and dansyl-L-proline were employed in the displacement measurements. Intrinsic fluorescence of tryptophan in HSA was monitored upon addition of the fatty acids into HSA. Electrocatalyzed response of the tyrosine residues in HSA by a redox mediator was used to investigate the binding interaction. Qualitatively, observations from these three approaches were very similar. HSA did not show any change in the fluorescence and electrochemical experiments after mixing with C2, suggesting there is no significant interaction with the short-chain fatty acid. For C8, the measured signal dropped in a single-exponential mode, indicating an independent and non-cooperative binding. The calculated association constant and binding ratio were 3.1 × 10^6 L/mol and 1 with drug binding Site Ⅰ, 1.1 × 107 L/mol and 1 with Site Ⅱ, and 7.0× 0^4 L/mol and 4 with the tryptophan site, respectively. The measurements with C12 displayed multiple phases of fluorescence change, suggesting cooperativity and allosteric effect of the C12 binding. These results correlate well with those obtained by the established methods, and validate the new approach as a viable tool to study the interactions of environmental pollutants with biological molecules.

Investigation of the interaction between indigotin and two serum albumins by spectroscopic approaches

The binding characteristics of indigotin with human serum albumin （HSA） and bovine serum albumin （BSA） have been investigated by various spectroscopic techniques. Spectroscopic analysis revealed that the quenching mechanism between indigotin and HSA/BSA belonged to the static quenching. The displacement experiments suggested that indigotin primarily bound to tryptophan residues on proteins within site I. The thermodynamic parameters indicated that the binding of indigoti^HSA/BSA mainly depended on the hydrophobic interaction. The binding distance of indigotin to HSA/BSA was evaluated. The results by synchronous fluorescence, three- dimensional fluorescence, Fourier Transform Infrared spectroscopy （FT-IR） and circular dichroism （CD） spectra showed that the conformation of proteins altered in the presence of indigotin.

Immobilization of Bovine Serum Albumin on Poly(ether ether ketone) for Surface Biocompatibility Improvement

UV-induced graft polymerization of acrylic acid（AA） on poly（ether ether ketone）（PEEK） films was carried out to introduce ―COOH for the subsequent immobilization of bovine serum albumin（BSA）.BSA was introduced on PEEK surface based on the condensation reaction between ―NH 2 and ―COOH.The modified surface（PEEK-BSA） was characterized by energy-disperse spectrometry（EDS）,X-ray photoelectron spectroscopy（XPS）,water contact angle measurement and UV spectrum analysis.The contact angle was found to decrease from 104° for the virgin PEEK films to 63° for the BSA-immobilized PEEK films,demonstrating a significant improvement of surface hydrophilicity.Moreover,the appearance of nitrogen on PEEK film confirmed by XPS and EDS indicates the immobilization of BSA on PEEK surface.

Dynamic Behaviors and Morphology Change of Anionic Phospholipid DPPG Monolayer Caused by Bovine Serum Albumin at Air-Water Interface

The interaction between bovine serum albumin （BSA） and the anionic 1.2-dipalmitoyl-snglycero- 3-（phospho-rac-（1-glycerol）） （sodium salt） （DPPG） phospholipid at different subphase pH values was investigated at air-water interface through surface pressure measurements and atomic force microscopy （AFM） observation. By analyzing surface pressure-mean molecular area （π-A） isotherms, the limiting molecular area in the closed packing state-the concentration of BSA （Alim-[BSA]） curves, the compressibility coefficient-surface pressure （CS-1-π） curves and the difference value of mean molecular area-the concentration of BSA （ΔA-[BSA]） curves, we obtained that the mean molecular area of DPPG monolayer became much larger when the concentration of BSA in the subphase increased at pH=3 and 5. But the isotherms had no significant change at different amount of BSA at pH=10. In addition, the amount of BSA molecules adsorbed onto the lipid monolayer reached a threshold value when [BSA]〉5×10-8 mol/L for all pHs. From the surface pressure-time （π-t） data, we obtained that desorption and adsorption processes occurred at pH=3, however, there was only desorption process occurring at pH=5 and 10. These results showed that the interaction mechanism between DPPG and BSA molecules was affected by the pH of subphase. BSA molecules were adsorbed onto the DPPG monolayers mainly through the hydrophobic interaction at pH=3 and 5, and the strength of hydrophobic interaction at pH=3 was stronger than the case of pH=5. At pH=10, a weaker hydrophobic interaction and a stronger electrostatic repulsion existed between DPPG and BSA molecules. AFM images revealed that the pH of subphase and [BSA] could affect the morphology features of the monolayers, which was consistent with these curves. The study provides an important experimental basis and theoretical support to understand the interaction between lipid and BSA at the air-water interface.

Sonocatalytic Damage of Bovine Serum Albumin (BSA) in the Presence of Nanometer Titanium Dioxide (TiO_2) Catalyst

The sonocatalytic damage of bovine serum albumin （BSA） was studied in the presence of nanometer titanium dioxide （TiO2） powders by low frequency （80 kHz） ultrasound. The destruction of secondary structure and change of α-helical structure of BSA were reflected by ultraviolet （UV） and circular dichroism （CD） spectroscopies.

Synthesis of Metal Porphyrins Tailed with Salicylic Acid and their Interaction with Bovine Serum Albumin

A synthetic method of porphyrins tailed with salicylic substituents is described. Reaction of bromoalkoxyphenyl porphyrin 1 with salicylic acid gave porphyrins 2~5. These new compounds were confirmed by 1H NMR, IR, UV-vis, MS and elemental analysis, and observed their interaction with bovine serum albumin (BSA) in fluorescence spectrum.

Antioxidant activity of bovine serum albumin binding amino acid Schiff-bases metal complexes

Glutamic acid-salicylaldehyde Schiff-base metal complexes are bound into bovine serum albumin （BSA）, which afforded BSA binding Schiff-base metal complexes （BSA-SalGluM, M=Cu, Co, Ni, Zn）. The BSA binding metal complexes were characterized by UV-vis spectra and Native PAGE. It showed that the protein structures of BSA kept after coordinating amino acid Schiff-bases metal complexes. The effect of the antioxidant activity was investigated. The results indicate that the antioxidant capacity of BSA increased more than 10 times after binding Schiff-base metal complexes.

Determination of Enantiomeric Compositions of Tryptophan by Chemometric Analysis of the Fluorescence Spectra of Bovine Serum Albumin Receptor-ligand Mixtures

In this work, a novel method was constructed to determine the enantiomeric composition of tryptophan （Trp） by bovine serum albumin （BSA） based on the fluorescence spectra of the receptor-ligand mixtures coupled with partial least squares （PLS-1） analysis. As a result the enantiomeric composition of Trp was accurately determined.