Serum Albumin Protein Research Articles

Assessing the prognostic value of C-reactive protein/albumin ratio and lactate/albumin ratio in critically ill patients

ABSTRACT Background: The ability to predict the fate of critically ill patients admitted to an intensive care unit is very important as there are only a few studies which have focused on this aspect. Our study focused to determine the relationship between C-reactive protein/albumin ratio (CAR) and lactate/albumin ratio (LAR) and intensive care unit stay, the requirement for vasopressor and mechanical ventilator support, and recovery and mortality in the patients admitted to critical care units. Methods: The study group comprised 100 patients who were admitted to critical care units. These patients were evaluated using a structured proforma, detailed case history, and clinical examination. Blood sample collection was done immediately after admission, and serum albumin, lactate, and C-reactive protein levels were estimated in these patients. Results: The mean age of the patients was 54.05. 74% of the patients were males. The common diagnosis was COVID bronchopneumonia. The patients with high LAR and high CAR values had either increased risk of mortality or increased duration of stay in the hospital (P = 0.0001). Patients with a low albumin level and high CRP required ventilator support, which was statistically significant. Patients who needed inotropic support and mechanical ventilator support had higher CAR (P = 0.001). Patients who received inotrope support had higher ESR and CRP levels. Conclusions: CAR and LAR are better indicators of mortality and duration of stay. CAR was found to be a better indicator of mortality than LAR, and it was also noted that the patients who required inotropes and mechanical ventilator support were found to have a higher CAR.

Synthesis and characterization of enhanced polysulfone-based mixed matrix membranes containing ZSM-5 zeolite for protein and dye removal

In this paper, polysulfone (PSf)-based ultrafiltration (UF) mixed matrix membranes (MMMs) embedded with ZSM-5 zeolite nanoparticles were synthesized via the NIPS method. The membranes were characterized by FESEM, ATR-FTIR, AFM, and tensile analyses, along with contact angle, porosity, and mean pore size measurements. The FESEM images indicated that the addition of hydrophilic ZSM-5 nanoparticles has led to formation of more and larger finger-like macrovoids. Moreover, hydrophilicity and pure water flux (PWF) values were consequently augmented, which was also approved by water contact angle reduction. The maximum PWF was equal to 394.7 L m-2h−1 at 3 bar for the optimum MMM, containing 1 wt% ZSM-5 which is 125.4 % greater than the value for the bare membrane. In addition, filtration of the bovine serum albumin (BSA) protein and aqueous solutions of two organic dyes were carried out. The highest BSA flux value was obtained 217.9 L m-2h−1 for the optimum membrane, where the BSA rejection values were all greater than 98 %. Furthermore, the optimum MMM displayed the highest flux recovery ratio (FRR%) of 60.1 % as well as the dyes rejection values equal to 95.5 % and 74.1 % for reactive black 5 (RB 5) and reactive yellow 160 (RY 160), respectively, representing its great potential to be applied in various wastewater treatment applications.

Artificial Simulation of Saliva's Astringency Removal Effect on Squid

Astringency is a common issue in squid processing and consumption. Various techniques such as soaking in salt water, adding acids, and using enzymes have been used to eliminate astringency. However, these methods have their limitations, and the search for a better solution is ongoing. In recent years, ultrasound technology has been proposed as an effective method for removing astringency in squid. This study used four proteins, including lysozyme, bovine serum albumin, collagen, and whey protein, to simulate saliva in the human oral cavity. This study aimed to determine the removal effect of squid astringency after saliva soaking and ultrasound treatment. Physicochemical indicators such as polyphenols and flavonoids, antioxidant activity, relative polymerization degree, and solution zeta potential were used as physicochemical indicators. Sensory evaluation and volatile salt nitrogen content were used as quality indicators of squid. The results indicated that artificial simulated saliva treatment significantly reduces polyphenols and antioxidant activity in squid muscle, reduces the content of volatile base nitrogen, eliminates the astringency of squid, and improves the taste and overall quality of squid. The technique of using ultrasound technology and artificial simulated saliva is a scientific and effective method for removing astringency in squid. This method has several advantages over traditional methods, including being a non-invasive method that does not require adding any chemicals, making it an environmentally friendly solution. The use of ultrasound technology allows for removing astringency in a shorter time than traditional methods. Finally, the technique is cost-effective and easily scaled up for industrial applications. In conclusion, using ultrasound technology and artificial simulated saliva treatment is a promising method for removing astringency in squid. The technique effectively removes astringency in squid muscle, improves the taste and overall quality of the squid, and is a non-invasive, environmentally friendly, cost-effective solution that can be easily scaled up for industrial application.

Differential scanning fluorimetry to assess PFAS binding to bovine serum albumin protein.

The rapid screening of protein binding affinity for poly- and perfluoroalkyl substances (PFAS) benefits risk assessment and fate and transport modelling. PFAS are known to bioaccumulate in livestock through contaminated food and water. One excretion pathway is through milk, which may be facilitated by binding to milk proteins such as bovine serum albumin (BSA). We report a label-free differential scanning fluorimetry approach to determine PFAS-BSA binding over a broad temperature range. This method utilizes the tryptophan residue within the protein binding pocket as an intrinsic fluorophore, eliminating the need for fluorophore labels that may influence binding. BSA association constants were determined by (a) an equilibrium-based model at the melting temperature of BSA and (b) the Hill adsorption model to account for temperature dependent binding and binding cooperativity. Differences in binding between PFAS and fatty acid analogs revealed that a combination of size and hydrophobicity drives PFAS binding.

Acute Oral Toxicological Profile of Croton membranaceus Mull. Arg. Aqueous Stem Extract, a Herbal Treatment for Benign Prostate Hyperplasia, in Male Sprague-Dawley Rats.

Croton membranaceus Mull. Arg. is a traditional medicinal plant frequently employed in Ghana for the treatment of benign prostatic hyperplasia and prostate cancer. The objective of this study was to determine the acute oral toxicity of the aqueous stem extract of Croton membranaceus (CMASE) in male Sprague-Dawley (S-D) rats. The acute toxicity of CMASE was evaluated using S-D rats randomly divided into four groups of five animals each. Three groups (low dose, median dose, and high dose) of rats received single oral doses of CMASE (1000, 2500, and 5000 mg/kg body weight, respectively) using an oral gavage. The control group was given distilled water. After 14 days of daily observations, hematological, biochemical, and histopathological analyses were conducted on the rats. From the results obtained, doses of CMASE up to 5000 mg/kg did not cause death or induce any clinical indications of toxicity during the study period. Also, the mean body weight and the hematological indices assessed were not significantly affected by the various doses of CMASE compared to the control group. However, serum uric acid and creatinine levels decreased significantly (p < 0.001) 14 days after the extract administration. Serum liver function enzyme levels, including alkaline phosphatase (ALP), alanine aminotransferases (ALT), and aspartate aminotransferases (AST), and serum proteins (total proteins and albumin) exhibited significant (p < 0.001) non dose-dependent changes (increases and decreases) in treated groups compared to the controls. Other biochemical indices, however, did not differ significantly between the treated groups and the controls. The gross pathological and histological analysis of the heart, liver, and kidney tissues did not reveal any significant changes in histoarchitecture. The oral LD50 of CMASE in rats was greater than 5000 mg/kg, indicating that the extract was relatively safe. It must, however, be used with care as a substitute for the roots.

SHH regulates penile morphology and smooth muscle through a mechanism involving BMP4 and GREM1.

The cavernous nerve (CN) is frequently damaged in prostatectomy and diabetic patients with erectile dysfunction (ED), initiating changes in penile morphology including an acute and intense phase of apoptosis in penile smooth muscle and increased collagen, which alter penile architecture and make corpora cavernosa smooth muscle less able to relax in response to neurotransmitters, resulting in ED. Sonic hedgehog (SHH) is a critical regulator of penile smooth muscle, and SHH treatment suppresses penile remodeling after CN injury through an unknown mechanism; we examine if part of the mechanism of how SHH preserves smooth muscle after CN injury involves bone morphogenetic protein 4 (BMP4) and gremlin1 (GREM1). Primary cultures of smooth muscle cells were established from prostatectomy, diabetic, hypertension and Peyronie's (control) (N= 18) patients. Cultures were characterized by ACTA2, CD31, P4HB, and nNOS immunohistochemical analysis. Patient smooth muscle cell growth was quantified in response to BMP4 and GREM1 treatment. Adult Sprague Dawley rats underwent 1 of 3 surgeries: (1) uninjured or CN-injured rats were treated with BMP4, GREM1, or mouse serum albumin (control) proteins via Affi-Gel beads (N = 16) or peptide amphiphile (PA) (N = 26) for 3 and 14days, and trichrome stain was performed; (2) rats underwent sham (N = 3), CN injury (N = 9), or CN injury and SHH PA treatment for 1, 2, and 4days (N = 9). Western analysis for BMP4 and GREM1 was performed; (3) rats were treated with 5E1 SHH inhibitor (N = 6) or IgG (control; N = 6) for 2 and 4days, and BMP4 and GREM1 localization was examined. Statistics were performed by analysis of variance with Scheffé's post hoc test. BMP4 increased patient smooth muscle cell growth, and GREM1 decreased growth. In rats, BMP4 treatment via Affi-Gel beads and PA increased smooth muscle at 3 and 14days of treatment. GREM1 treatment caused increased collagen and smooth muscle at 3days, which switched to primarily collagen at 14days. CN injury increased BMP4 and GREM1, while SHH PA altered Western band size, suggesting alternative cleavage and range of BMP4 and GREM1 signaling. SHH inhibition in rats increased BMP4 and GREM1 in fibroblasts. Understanding how SHH PA preserves and regenerates penile morphology after CN injury will aid development of ED therapies. SHH treatment alters BMP4 and GREM1 localization and range of signaling, which can affect penile morphology. Part of the mechanism of how SHH regulates corpora cavernosa smooth muscle involves BMP4 and GREM1.

Geriatric nutrition risk index: a more powerful index identifying muscle mass loss in patients with rheumatoid arthritis.

To explore the association of geriatric nutrition risk index (GNRI), a traditional albumin-body weight calculation, with myopenia in patients with rheumatoid arthritis (RA) and compare its ability to identify myopenia with protein indicators. This cross-sectional study was carried out based on a Chinese RA cohort. Clinical data and protein indicators (including albumin, globulin, albumin to globulin ratio, prealbumin, hemoglobin) were collected. GNRI was estimated by serum albumin and body weight. Myopenia was indicated as muscle mass loss measured by bioelectric impedance analysis. There were 789 RA patients included with mean age 52.6 ± 12.6years and 77.6% female. There were 41.3%, 18.0%, 27.5%, 13.2% patients with no (GNRI > 98), low (GNRI 92 to ≤ 98), moderate (GNRI 82 to < 92), and major nutrition-related risk (GNRI < 82). There were 406 (51.5%) RA patients with myopenia, RA patients with major nutrition-related risk had the highest prevalence of myopenia (87.5% vs. 73.3% vs. 50.0% vs. 26.1%). Multivariate logistic analysis showed that compared with no risk, RA patients with low (OR = 3.23, 95% CI: 1.86-5.61), moderate (OR = 9.56, 95% CI: 5.70-16.01), and major nutrition-related risk (OR = 28.91, 95% CI: 13.54-61.71) were associated with higher prevalence of myopenia. Receiver operating characteristic curves showed that GNRI (AUC = 0.79) performed a better identifiable ability toward myopenia than serum albumin (AUC = 0.66) or others indicators (AUC range 0.59 to 0.65), respectively. GNRI, an objective and convenient albumin-weight index, may be preferable for identifying myopenia in RA patients. Key Points • We firstly elucidated the association of GNRI with muscle mass loss among RA patients, and compared its ability to identify muscle mass loss with serum albumin or other protein indicators. • Major nutrition-related risk identified by GNRI showed the highest risk of muscle mass loss, GNRI demonstrated a greater ability to identify myopenia in RA patients. which indicated GNRI was an objective and convenient albumin-weight index to identify myopenia in RA patients.

The interactions of antiviral drugs and a phosphonium fluorescent dye with proteins as revealed by a multiple ligand simultaneous docking

In the present study, the multiple ligands simultaneous docking technique was employed to explore the feasibility of developing the protein-based nanocarriers in which the therapeutic agents (antiviral drugs) will be combined with a visualizing agent (the phosphonium dye TDV). By varying both the protein (serum albumin, lyso-zyme, cytochrome c, insulin) and antiviral agent (favipiravir, molnupiravir, nirmatrelvir, ritonavir) components of the examined complexes it was demonstrated that in the albumin- and cytochrome c-containing systems the TDV and antiviral dyes occupy distinct binding sites on the protein molecule, exhibiting no interference with each other. It was found that the TDV propensity to reside within the same insulin cavity as the antiviral agent might hinder the drug’s release from the nanocarrier. Our results indicate that the most promising energetically stable protein-drug-TDV systems for developing protein-based nanocarriers with the examined antiviral drugs can be created on a basis of serum albumin.

A Bis(Aquated) Mn(II)-Based MRI Contrast Agent with a Rigid Hydroquinazoline Unit: Synthesis, Characterization, and in Vivo MR Imaging Study.

Since the finding of nephrogenic systemic fibrosis (NFS) in patients with renal impairment and the long-term accumulation of Gd(III) ions in the central nervous system, the search for nongadolinium ion-based MRI contrast agents made of nutrient metal ions has drawn paramount attention. In this context, the development of Mn(II)-based MRI contrast agents has been a subject of interest for the last few decades. Herein, we report a pentadentate ligand (Li2[BenzPic2]) composed of two picolinate moieties and a rigid 1,2,3,4-tetrahydroquinazoline unit and the corresponding bis(aquated) Mn(II) complex (Complex 1). The complex exhibited high thermodynamic stability (log Kcond = 11.62) and kinetic inertness similar to that of the clinically approved Gd(III)-based contrast agent Magnevist. Complex 1 exerted longitudinal relaxivity (r1) of 5.32 mM-1 s-1 at 1.41 T, 37 °C, pH 7.4, and it increased by 3.6-fold in the presence of serum albumin protein, confirming a substantial rigidifying interaction (albumin association constant KA = 1.66 × 103 M-1) between the protein and the amphiphilic (log P = -0.45) contrast agent. An intravenous dose of 0.08 mmol/kg in a healthy mouse, excellent MRI signal intensity enhancement in the vasculature of the mouse liver, and brightened images of the gallbladder, kidney, and liver were realized.

Simultaneous Purification of Human Interferon Alpha-2b and Serum Albumin Using Bioprivileged Fluorinated Ionic Liquid-Based Aqueous Biphasic Systems.

Interferon alpha-2b (IFN-α2b) is an essential cytokine widely used in the treatment of chronic hepatitis C and hairy cell leukemia, and serum albumin is the most abundant plasma protein with numerous physiological functions. Effective single-step aqueous biphasic system (ABS) extraction for the simultaneous purification of IFN-α2b and BSA (serum albumin protein) was developed in this work. Effects of the ionic liquid (IL)-based ABS functionalization, fluorinated ILs (FILs; [C​2C​1Im][C​4F​9SO​3] and [N​1112(OH)][C​4F​9SO​3]) vs. mere fluoro-containing IL ([C​4C​1Im][CF​3SO​3]), in combination with sucrose or [N​1112(OH)][H​2PO​4] (well-known globular protein stabilizers), or high-charge-density salt K​3PO​4 were investigated. The effects of phase pH, phase water content (%wt), phase composition (%wt), and phase volume ratio were investigated. The phase pH was found to have a significant effect on IFN-α2b and BSA partition. Experimental results show that simultaneous single-step purification was achieved with a high yield (extraction efficiency up to 100%) for both proteins and a purification factor of IFN-α2b high in the enriched IFN-α2b phase (up to 23.22) and low in the BSA-enriched phase (down to 0.00). SDS-PAGE analysis confirmed the purity of both recovered proteins. The stability and structure of IFN-α2b and BSA were preserved or even improved (FIL-rich phase) during the purification step, as evaluated by CD spectroscopy and DSC. Binding studies of IFN-α2b and BSA with the ABS phase-forming components were assessed by MST, showing the strong interaction between FILs aggregates and both proteins. In view of their biocompatibility, customizable properties, and selectivity, FIL-based ABSs are suggested as an improved purification step that could facilitate the development of biologics.

Partial purification and characterization of protease extracted from kinema

Proteases are large group of highly demanded enzymes having huge application in food and pharmaceutical industries. Numerous sources, including plants, microorganisms, and animals, can be used to obtain protease. Due to its affordability and safety consideration, fermented foods have recently attracted more attention as a source of microbial protease. The present study aimed to extract protease from kinema, partially purify the extracted protease following dialysis after precipitation with ammonium sulfate, and determine general characteristics of protease. The kinema having highest proteolysis activity after three days of control fermentation (Temperature 30±2 °C, RH 66 ± 2%) was taken for the study. About 2.45 fold of purification with overall recovery of 63.21% was achieved after precipitation with ammonium sulfate at 30–70% saturation level followed by dialysis of crude extracted protease. The dialysed kinema protease had specific activity of 7.90 U/mg. The enzyme remained actively functional across a wider pH (5–9) and temperature (40-60 °C) range. SDS-PAGE and Zymogram confirmed the presence of three major active bands respectively of 29.04 kDa, 36.09 kDa and 46.35 kDa in the kinema protease extract. The enzyme kinetics data on casein, fitted to Mechaelis Mentens’ plots showed the protease had Vmax of 1.001 U/ml with corresponding Km value of 0.825 mg/ml. Metal ions such as iron, mercury and aluminium showed the inhibition effect whereas presence of sodium, zinc, and calcium shows the activation effect on protease performance. The enzyme was active over various natural substrates; showing maximal activity on casein, and subsequent to bovine serum albumin, gelatin, hemoglobin and whey protein respectively. Furthermore, molecular weight distribution of the protease extract and activity inhibition with ethylenediaminetetraacetic acid and phenylmethylsulfonyl fluoride, suggesting the protease from kinema could be a metal dependent serine protease or mixture of them.

Alkaline-oxidized MXene composite membrane of ultra high flux and advanced rejection performance for water purification

MXene is a metal-carbon/nitrogen compound material with a two-dimensional layered structure. As a new form of two-dimensional material, it has great potential in the field of water purification because of its properties of high permeability and hydrophilicity. In this study, a MXene composite membrane was prepared by in-situ oxidation of titanium dioxide on the MXene surface by an alkaline oxidation method. A series of characterizations of the prepared MXene composite membrane was carried out. Scanning electron microscopy showed that with an increasing degree of oxidation, the extent of agglomeration of MXene nanosheets increased, thus generating more water channels that are conducive to the transport of water molecules, and an increasing water flux. The penetration performance, interception performance, and stability of the MXene composite membrane were tested. The effect of different concentrations of KOH on the properties of the composite membrane was investigated. It was found that the flux of the composite membrane increased with alkali concentration by 4.6–28.8 times the flux without exposure to alkali. It was found that the rejection rate of the composite membrane for pollutants (dyes, humic acid, bovine serum albumin protein) decreased only slightly with increasing alkali concentration, and was ≥94% of the pure MXene membrane rejection rate in all cases. The rejection performance of the composite membrane was related to the size and charge properties of the pollutant molecules. The results of the stability tests showed that the composite membranes had a high degree of physical and flux stability in a range of aqueous solutions.

Comparative evaluation of GSH, total protein and albumin levels in patients using smokeless tobacco with oral precancerous and cancerous lesions.

Smokeless tobacco (SLT) causes the excessive production of reactive oxygen species, leading to oxidative damage and carcinogenesis. The present study aimed to evaluate the levels of biomarkers, such as glutathione (GSH) in the blood, as well as serum albumin and total protein levels in SLT users with oral precancerous and cancerous lesions. A cross-sectional, prospective study was conducted on 240 patients aged 30-60 years, divided into four groups with 60 patients in each group as follows: Group 1, control group, non-tobacco users; group 2, 60 subjects with a history of SLT use and no oral lesions; group 3, SLT users with precancerous oral lesions; and group 4, SLT users with cancerous lesions. GSH levels in the blood, serum albumin levels and total protein levels were evaluated in all groups. ANOVA and Tukey's test post hoc were used to compare the levels of the biomarkers in all groups. Receiver operating characteristic curves were used to assess the reliability of the biomarkers, and regression analysis was used to determine the associations between the variables. The use of SLT was predominantly observed in males. The mean GSH and serum albumin levels were lowest in group 4 and highest in the control group (P<0.001). The total serum protein levels were higher in group 4 than in group 3. On the whole, as demonstrated herein, GSH and serum albumin were reliable biomarkers, whereas total protein was a weak biomarker. GSH and serum albumin levels may thus be efficiently used for the early diagnosis and prognosis of oral malignancies in SLT users.

Different behavior of Ferguson plot between agarose and polyacrylamide gels

In this study, we conducted Ferguson plot analyses using both agarose and polyacrylamide gels in native electrophoresis and SDS-PAGE. The results revealed intriguing differences in the behavior of bovine serum albumin (BSA) and other model proteins. Specifically, BSA exhibited Ferguson plot slopes that were dependent on the oligomer size in agarose native gel electrophoresis, while such size-dependent behavior was not observed in native-PAGE or SDS-PAGE. These findings suggest that Ferguson plot analysis is a suitable approach when using agarose gel under the electrophoretic conditions employed in this study. Furthermore, our investigation extended to model proteins with acidic isoelectric points and larger molecular weights, namely Ferritin and caseinolytic peptidase B (ClpB). Notably, these proteins displayed distinct Ferguson plot slopes when subjected to agarose gel electrophoresis. Intriguingly, when polyacrylamide gel was employed, ClpB exhibited multiple bands, each with its unique Ferguson plot slope, deviating from the expected behavior based on molecular size. This divergence in Ferguson plot characteristics between agarose and polyacrylamide gels points to an interesting and complex interplay between protein properties and gel electrophoresis conditions.

Evaluation of Antioxidant, Anti-inflammatory, and Antimicrobial Activities of Raspberry Fruit Extract: An In Vitro Study.

Introduction Rubus idaeus (R. idaeus)is an edible fruit thatcontains numerous significant bioactive compounds that hold important biological properties and are categorized as nutraceuticals owing to the health benefits it imparts including decreasing the risk of chronic diseases like diabetes mellitus, cancer, heart disease, and many other diseases.The objective of the present research was to explorethe antimicrobial, antioxidant, and anti-inflammatory characteristics of the aqueous raspberry extractthrough in vitro assays. Materials and methods R. idaeus aqueous extract was prepared and examined for its antimicrobial activity against Streptococcus mutans (S. mutans) bacteria and Candida albicans (C. albicans) fungi using the agar-well diffusion method, and the antioxidant activity was evaluated using the DPPH (2, 2-Diphenyl-1-picrylhydrazyl hydrate) radical scavenging assay and the hydrogen peroxide radical scavenging assay. The anti-inflammatory activity of the prepared extract was investigated using bovine serum albumin (BSA) and egg albumin denaturation assays. Results R. idaeus fruit extract displayed strong antimicrobial activity at a higher concentration of 100 µL with a 26 mm zone of inhibition against Streptococcus mutans and 24 mm for Candida albicans. The extract showed 87.42% hydrogen peroxide free radical scavenging activity and inhibited 91.12% DPPH free radicals at the highest concentration of 50 µg/mL. The extract showed effective anti-inflammatory activity by preventing the denaturation of bovine serum albumin (80%) and egg albumin proteins (77%) at the highest concentration of 50 μg/mL.The free radical scavenging activity positively correlates with the increased concentration of the prepared extract against DPPH and hydrogen peroxide free radicals, thus showing the raspberry extract's potent antioxidant activity. Similarly, the anti-inflammatory assay result shows that the prepared raspberry aqueous extract has excellent anti-inflammatory activity by preventing the denaturation of bovine serum albumin and egg albumin protein in a dose-dependent manner. Conclusion The meticulously prepared raspberry extract exhibited noteworthy antimicrobial, antioxidant, and anti-inflammatory characteristics, and owing to its astounding therapeutic benefits it holds a tremendous promise as a natural alternative in the field of oral medicine especially in the management of oral mucosal lesions, oral potentially malignant lesions such as lichen planus and leukoplakia, candidiasis, oral cancer and oral mucositis. Further animal studies and clinical trials are recommended to fully reap the therapeutics potential of raspberry extract.

Clinical Observation of Serum Anti-PLA2R Antibody Levels in the Treatment of Idiopathic Membranous Nephropathy with Rituximab

Objective: To investigate the efficacy of rituximab in the treatment of idiopathic membranous nephropathy with varying levels of serum phospholipase A2 receptor antibodies. Methods: A total of 137 patients with idiopathic membranous nephropathy admitted to Beijing Sixth Hospital were selected. Based on their blood PLA2R antibody levels before rituximab treatment, patients were categorized into the PLA2R antibody positive group (n = 94) and the PLA2R antibody negative group (n = 43). They were followed up for at least 1 year, during which the efficacy, measured through 24-hour urine protein quantification and serum albumin levels, were compared between the two groups before and after treatment. Results: After 3 months of treatment, there was no significant difference in the quantitative levels of 24-hour urine protein between the two groups (P &gt; 0.05). However, after 6 and 12 months of treatment, there was a significant difference in the levels of 24-hour urine protein between the two groups (P &lt; 0.05). Additionally, after 3 months of treatment, there was a notable difference in the serum albumin levels between the two groups (P &lt; 0.05). However, after 6 and 12 months of treatment, there was no significant difference in serum albumin levels between the two groups (P &gt; 0.05). Analysis of complications in the two groups revealed that in the positive group, 9 individuals experienced thrombosis, 5 had infections, and 11 developed acute kidney injury (AKI). In contrast, in the negative group, 5 individuals had thrombosis, 2 had infections, and 3 developed AKI. There was no statistically significant difference in complications between the two groups (P &gt; 0.05). Conclusion: Serum anti-PLA2R antibody levels provide valuable insights into the clinical observation of rituximab treatment for idiopathic membranous nephropathy. They aid in understanding the disease’s pathogenesis, evaluating treatment efficacy, and predicting disease prognosis.

Next-Generation Tags for Fluorine Nuclear Magnetic Resonance: Designing Amplification of Chemical Shift Sensitivity.

Fluorine NMR is a highly sensitive technique for delineating the conformational states of biomolecules and has shown great utility in drug screening and in understanding protein function. Current fluorinated protein tags leverage the intrinsic chemical shift sensitivity of the 19F nucleus to detect subtle changes in protein conformation and topology. This chemical shift sensitivity can be amplified by embedding the fluorine or trifluoromethyl reporter within a pyridone. Due to their polarizability and rapid tautomerization, pyridones exhibit a greater range of electron delocalization and correspondingly greater 19F NMR chemical shift dispersion. To assess the chemical shift sensitivity of these tautomeric probes to the local environment, 19F NMR spectra of all possible monofluorinated and trifluoromethyl-tagged versions of 2-pyridone were recorded in methanol/water mixtures ranging from 100% methanol to 100% water. 4-Fluoro-2-pyridone and 6-(trifluoromethyl)-2-pyridone (6-TFP) displayed the greatest sensitivity of the monofluorinated and trifluoromethylated pyridones, exceeding that of known conventional CF3 reporters. To evaluate the utility of tautomeric pyridone tags for 19F NMR of biomolecules, the alpha subunit of the stimulatory G protein (Gsα) and human serum albumin (HSA) were each labeled with a thiol-reactive derivative of 6-TFP and the spectra were recorded as a function of various adjuvants and drugs. The tautomeric tag outperformed the conventional tag, 2-bromo-N-(4-(trifluoromethyl)phenyl)acetamide through the improved resolution of several functional states.

Crystal structure of human serum albumin in complex with megabody reveals unique human and murine cross-reactive binding site.

The pharmacokinetic properties of small biotherapeutics can be enhanced via conjugation to cross-reactive albumin-binding ligands in a process that improves their safety and accelerates testing through multiple pre-clinical animal models. In this context, the small and stable heavy-chain-only nanobody NbAlb1, capable of binding both human and murine albumin, has recently been successfully applied to improve the stability and prolong the in vivo plasma residence time of multiple small therapeutic candidates. Despite its clinical efficacy, the mechanism of cross-reactivity of NbAlb1 between human and murine serum albumins has not yet been investigated. To unveil the molecular basis of such an interaction, we solved the crystal structure of human serum albumin (hSA) in complex with NbAlb1. The structure was obtained by harnessing the unique features of a megabody chimeric protein, comprising NbAlb1 grafted onto a modified version of the circularly permutated and bacterial-derived protein HopQ. This structure showed that NbAlb1 contacts a yet unexplored binding site located in the peripheral region of domain II that is conserved in both human and mouse serum albumin proteins. Furthermore, we show that the binding of NbAlb1 to both serum albumin proteins is retained even at acidic pH levels, thus explaining its extended in vivo half-life. The elucidation of the molecular basis of NbAlb1 cross-reactivity to human and murine albumins might guide the design of novel nanobodies with broader reactivity toward a larger panel of serum albumins, thus facilitating the pre-clinical and clinical phases in humans.

Porous Laser-Scribed Graphene Electrodes Modified with Zwitterionic Moieties: A Strategy for Antibiofouling and Low-Impedance Interfaces.

Laser-scribed graphene electrodes (LSGEs) are promising platforms for the development of electrochemical biosensors for point-of-care settings and continuous monitoring and wearable applications. However, the frequent occurrence of biofouling drastically reduces the sensitivity and selectivity of these devices, hampering their sensing performance. Herein, we describe a versatile, low-impedance, and robust antibiofouling interface based on sulfobetaine-zwitterionic moieties. The interface induces the formation of a hydration layer and exerts electrostatic repulsion, protecting the electrode surface from the nonspecific adsorption of various biofouling agents. We demonstrate through electrochemical and microscopy techniques that the modified electrode exhibits outstanding antifouling properties, preserving more than 90% of the original signal after 24 h of exposure to bovine serum albumin protein, HeLa cells, and Escherichia coli bacteria. The promising performance of this antifouling strategy suggests that it is a viable option for prolonging the lifetime of LSGEs-based sensors when operating on complex biological systems.

Adsorption of Organic Pollutants on Carbonaceous Adsorbents Prepared by Direct Activation of Sweet Cherry Stones.

The main objective of this study was to assess the usefulness of the sweet cherry stones for the production of carbonaceous adsorbents by means of direct physical activation method, using conventional and microwave variant of heating. The adsorbents were characterized in terms of textural parameters, acidic-basic character of the surface, electrokinetic properties and their suitability for drinking water purification. Adsorption tests were carried out against three organic compounds - Triton X-100 (surfactant), bovine serum albumin (protein) and methylene blue (synthetic dye). Depending on the variant of heating applied during activation procedure, the obtained activated biochars differed significantly in terms of the elemental composition, acidic-basic properties as well as degree of specific surface development and the type of porous structure generated. Adsorption tests have showed that the efficiency of organic pollutants removal from aqueous solutions depends significantly not only on the type of the adsorbent and adsorbate applied, but also on the temperature and pH of the system. The sample prepared by microwave-assisted direct activation proved to be very effective in terms of all tested organic pollutants adsorption. The maximum sorption capacity toward Triton X-100, bovine serum albumin and methylene blue reached the level of 86.5, 23.4 and 81.1 mg/g, respectively.