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.

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.

Competitive Adsorption between Bovine Serum Albumin and Collagen Observed by Atomic Force Microscope

Atomic force microscopy (AFM) was used to study the competitive adsorption betweenbovine serum albumin (BSA) and type Ⅰ collagen on hydrophilic and hydrophobic silicon wafers.BSA showed a grain shape and the type Ⅰ collagen displayed fibril-like molecules with relativelyhomogeneous height and width, characterized with clear twisting (helical formation). These AFMimages illustrated that quite a lot of type Ⅰ collagen appeared in the adsorption layer on hydrophilicsurface in a competitive adsorption state, but the adsorption of BSA was more preponderant than thatof type Ⅰ collagen on hydrophobic silicon wafer surface. The experiments showed that theinfluence of BSA on type Ⅰ collagen adsorption on hydrophilic surface was less than that onhydrophobic surface.

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.

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.

Multi-spectroscopic characterization of bovine serum albumin upon interaction with atomoxetine

The quenching interaction of atomoxetine(ATX) with bovine serum albumin(BSA) was studied in vitro under optimal physiological condition(pH=7.4) by multi-spectroscopic techniques. The mechanism of ATX-BSA system was a dynamic quenching process and was confirmed by the fluorescence spectra and lifetime measurements. The number of binding sites, binding constants and other binding characteristics were computed. Thermodynamic parameters ΔH^0 and ΔS^0 indicated that intermolecular hydrophobic forces predominantly stabilized the drug-protein system. The average binding distance between BSA and ATX was studied by F?rsters theory. UV-absorption, Fourier transform infrared spectroscopy(FT-IR), circular dichroism(CD), synchronous spectra and three-dimensional(3D) fluorescence spectral results revealed the changes in micro-environment of secondary structure of protein upon the interaction with ATX. Displacement of site probes and the effects of some common metal ions on the binding of ATX with BSA interaction were also studied.

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.

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.

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.

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.

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.

Characterization of Interaction Between Raltitrexed and Bovine Serum Albumin by Optical Spectroscopic Techniques

The interaction of raltitrexed（RTX） with bovine serum albumin（BSA） was investigated by steady state/lifetime fluorescence spectroscopy and circular dichroism（CD） spectroscopy under the simulative physiological conditions.The results of fluorescence titration reveal that RTX could strongly quench the intrinsic fluorescence of BSA via a static quenching procedure.The obtained binding constant K A of RTX with BSA was 478630 and 44259 L/mol at 298 and 310 K,respectively.According to van＇t Hoff equation,the thermodynamic parameters ΔH,ΔG and ΔS were calculated,indicating that hydrophobic forces were the predominant intermolecular forces in stabilizing the complex.The binding process was a spontaneous process,in which Gibbs free energy change was negative.According to F rster＇s non-radioactive energy transfer theory,the distance r between donor（BSA） and acceptor（RTX） was 3.82 nm,suggesting that the energy transfer from BSA to RTX occurred with high probability.Displacement experiment and the number of binding sites calculation confirmed that RTX could bind to the site-I of BSA.Furthermore,the effects of pH and some metal ions on the interaction of RTX with BSA were also investigated.The results of synchronous fluorescence and CD spectra show that the RTX-BSA binding induced conformational changes in BSA.

Using capillary electrophoresis mobility shift assay to study the interaction of CdTe quantum dots with bovine serum albumin

In this work, the capillary electrophoresis mobility shift assay （CEMSA） was first adopted to study the interaction of protein with quantum dots （QDs）. In this study, bovine serum albumin （BSA） and CdTe QDs were used as model samples. We observed that BSA was facilely adsorbed to CdTe QDs surface, and the QD-BSA complex was formed by a 1：1 stoichiometric ratio. A value of 2.17 4-0.27 × 10^6 mol^-1 L^-1 （at 25 ℃） for the association constant was obtained by CEMSA.

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.

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 of <i>in Vitro</i>Interaction of Sildenafil Citrate with Bovine Serum Albumin by Fluorescence Spectroscopy

In vitro interaction of sildenafil citrate (SC) with bovine serum albumin (BSA) was investigated at two excitation wavelengths of BSA (280 nm and 293 nm) at two different temperatures (298 K and 308 K) by fluorescence emission spectroscopy. The study showed that quenching of BSA fluores-cence by sildenafil citrate was the result of formation BSA-SC complex with probable involvement of both tryptophan and tyrosine residues of BSA. Fluorescence quenching constant was determined from Stern-Volmer equation, and both static quenching and dynamic quenching were showed for BSA by SC at the conditions. Van’t Hoff equation was used to measure the thermodynamic parameters ΔG, ΔH, and ΔS at the temperatures which indicated that the hydrogen bond and the hydrophobic forces played major roles for BSA-SC complexation. The binding number (n) was found to be ≈1 indicating that one mole BSA bound with one mole SC. The binding affinity of SC to BSA was calculated at different temperatures. The binding constant was decreased with increasing temperatures indicating that stability of BSA-SC complex decreased with increasing temperatures.

Bovine serum albumin:An efficient and green biocatalyst for the one-pot four-component synthesis of pyrano[2,3-c]pyrazoles

The use of biocatalysts is attracting an increasing amount of attention in chemical catalysis.Here,we have shown that bovine serum albumin（BSA）,a ubiquitous,inexpensive,non-enzymatic transport protein,can serve as an efficient,retrievable catalyst in the one-pot four-component reaction of aryl aldehydes,malononitrile,hydrazine hydrate,and ethyl acetoacetate for the synthesis of pyrano[2,3-c]pyrazoles under mild reaction conditions.The BSA biocatalyst also displayed a high catalytic affinity for acyclic/cyclic ketones to yield the corresponding pyrano[2,3-c]pyrazoles or their spirocyclic variants.The BSA could be used for at least five cycles without serious loss of catalytic activity.This novel,efficient protocol has the merits of high yield,operational simplicity,and a relatively benign environmental impact.Moreover,the method extends the promiscuity of BSA as a biocatalyst.

Morphological characterization of metal porphyrin tailed with aspirin interacting with bovine serum albumin congeries

The porphyrins tailed with acetylsalicylic acid （ASA） and Zn （or Cu） complexes were prepared. Meanwhile, morphological images, such as shape and size of porphyrins-BSA congeries were observed by using atomic force microscopy （AFM）. The result showed the interaction of BSA and prepared porphyrins led to obvious change of shape and size of BSA congeries.

Reduced graphene oxide-grafted bovine serum albumin/bredigite nanocomposites with high mechanical properties and excellent osteogenic bioactivity for bone tissue engineering

The optimization of the scaffolds to provide a suitable matrix and accelerate the regeneration process is vital for bone tissue engineering.However,poor mechanical and biological characteristics remain the primary challenges that must be addressed.For example,although bredigite(Br)has shown great potential for application in bone tissue engineering,it easily fails in replacement.In the present work,these challenges are addressed by reinforcing the Br matrix with nanosheets of graphene oxide(rGO)that have been reduced by bovine serum albumin(BSA)in order to enhance the mechanical properties and biological behavior.The reduction of graphene oxide by BSA improves the water stability of the nanosheets and provides an electrostatic interaction between theBSA-rGO nanosheets and theBr particles.The high thermal conductivity of theBSA-rGO nanosheets decreases the porosity of the Br by transferring heat to the core of the tablet.Furthermore,the addition of BSA-rGO nanosheets into the Br matrix enhances the adhesion of G-292 cells on the surface of the tablets.These findings suggest that the tablet consisting of BSA-rGO-reinforced Br has encouraging potential for application in bone tissue engineering.