Varying Amounts Of Protein Research Articles

Rice Bran Valorization through the Fabrication of Nanofibrous Membranes by Electrospinning

The high production rate of fossil-based plastics, coupled with their accumulation and low degradability, is causing severe environmental problems. As a result, there is a growing interest in the use of renewable and natural sources in the polymer industry. Specifically, rice bran is a highly abundant by-product of the agro-food industry, with variable amounts of protein and starch within its composition, which are usually employed for bioplastic development. This study aims to valorize rice bran through the production of nanofiber membranes processed via electrospinning. Due to its low solubility, the co-electrospinning processing of rice bran with potato starch, known for its ability to form nanofibers through this technique, was chosen. Several fiber membranes were fabricated with modifications in solution conditions and electrospinning parameters to analyze their effects on the synthesized fiber morphology. This analysis involved obtaining micrographs of the fibers through scanning electron microscopy (SEM) and fiber diameter analysis. Potato starch membranes were initially investigated, and once optimal electrospinning conditions were identified, the co-electrospinning of rice bran and potato starch was conducted. Attempts were made to correlate the physical properties of the solutions, such as conductivity and density, with the characteristics of the resulting electrospun fibers. The results presented in this study demonstrate the potential valorization of a rice by-product for the development of bio-based nanofibrous membranes. This not only offers a solution to combat current plastic waste accumulation but also opens up a wide range of applications from filtration to biomedical devices (i.e., in tissue engineering).

Studying the effect of experimental infection with Eimeria Maxima and various amounts of protein on the performance of producing broilers

Studying the effect of experimental infection with Eimeria Maxima and various amounts of protein on the performance of producing broilers

Fractionation and characterization of cell wall polysaccharides from coffee (Coffea arabica L.) pulp

Cell wall polysaccharides were isolated by sequential extractions from coffee pulp, the main solid waste from coffee processing. Extractions were conducted with distilled water at room and boiling temperatures, 0.5 % ammonium oxalate and 0.05 M Na2CO3 to obtain pectic fractions. Hemicelluloses were extracted by using 2 M and 4 M NaOH. The composition of the hemicellulose fractions suggested the presence of xyloglucans, galactomannans and arabinogalactan-proteins (AGPs). The main part of the cell wall polysaccharides recovered from coffee pulp were pectins branched with arabinogalactans. Coffee pulp pectic fractions were low-methoxylated with various amounts of protein (0.5–8.4 %) and phenolics (0.7–8.5 %). Detection at 280 nm in the HPSEC analyses and radial gel diffusion assay using Yariv reagent indicated the presence of AGPs in most of these fractions. NMR analyses of chelating agent (CSP) and dialyzed water (WSPD) extracted pectins were carried out. The results demonstrated that CSP contains only AG I. On the other hand, AG I and AG II are present in WSPD, probably covalently linked to the pectic portion. Comparison with the literature indicated similarities between the cell wall polysaccharides from coffee pulp and green coffee beans.

Immunoglobulin G in Platelet-Derived Wound Healing Factors.

We intended to reformulate an existing platelet-derived wound healing formula to target each phase of the healing wound with the appropriate phase-specific molecules. A decreased perfusion of the skin, often associated with conditions such as thalassemia, sickle cell disease, diabetes mellitus, and chronic vascular disease, is the most common etiology of cutaneous ulcers and chronic wounds. We had previously shown that a PDWHF topically applied to a chronic nonhealing ulcer of a β-thalassemia homozygote stimulated and accelerated closure of the wound. The PDWHF was prepared from a pooled platelet concentrate of a matching blood group, consisting of a combination of platelet α-granule-derived factors. Processing of the apheresis-pooled platelets yielded various amounts of proteins (3.36 g/mL ± 0.25 (SD) (N = 10)) by the better lysis buffer method. Immunoglobulin G was found to be the most abundant α-granule-secreted protein. Equally broad quantities of the IgG (10.76 ± 12.66% (SD) (N = 10)) and IgG/albumin ratios (0.6 ± 0.4 (SD) (N = 10)) were quantified. We have developed a method using a reformulated lysis buffer followed by size exclusion chromatography and affinity chromatography to extract, identify, quantify, and purify IgG from activated platelets. IgG purification was confirmed by Western blot and flow cytometry. It was thought unlikely that the platelet IgG could be accounted for by adsorption of plasma protein, though the variable quantities could account for diversity in wound healing rates. The IgG could protect the wound even from subclinical infections and functionally advance healing. It may be useful in the management of skin ulcers in the early phase of wound healing.

Should Intravenous Immunoglobulin G (IVIg) be used in the treatment of COVID-19?

KEY FINDINGS
 There is conflicting evidence on the efficacy of intravenous immunoglobin G in the treatment of COVID-19 
 patients with severe disease. 
 
 Intravenous immunoglobulin G (IVIg) is a mixture of polyclonal immunoglobulin G (IgG3, IgG4) antibodies as well as variable amounts of proteins; IgA, IgE and IgM antibodies isolated and pooled from healthy donors. IgG is involved in viral neutralization, modulates anti-inflammatory cytokines and cytokine antagonists.
 
 
 Immediate adverse effects of IVIg include flu-like syndrome, dermatologic side effects, arrhythmia, hypotension, and transfusion-related acute lung injury (TRALI). Delayed adverse effects can involve any organ which could be severe or even lethal
 
 
 There was a retrospective study (Yun Xie 2020) and several case reports that described recovery of COVID positive patients with severe disease. However, a retrospective study showed that immunoglobulin G with steroids and antivirals did not improve COVID patients with acute respiratory distress syndrome (Liu Y 2020). Similarly, another study showed no significant difference in the 28- and 60-day mortality between the IVIg and non-IVIg groups but subgroup analyses reported that in those with critical COVID illness, 28 day mortality is decreased with IVIg (Shao Z).
 
 
 There are eight registered clinical trials on the use of intravenous immunoglobulin G in COVID-19 patients.

Effects of different proteins on the rheological properties of rice batter and characteristics of fermented rice cakes

The effects of soy protein isolate (SPI), whey protein concentrate (WPC), and marine fish collagen (MFC) on the dynamic rheological properties of rice batter and the quality of fermented rice cakes (FRCs) during 3 days of storage at 20°C were determined. The rice batters with SPI, WPC, and MFC had higher phase shift tangent values than the control, but still exhibited strong elastic and weak viscous gel behaviors. The addition of MFC increased the porosity and specific volume, enhanced the surface color brightness, and significantly decreased the crumb firming rate, improved the sensory quality, and retarded amylopectin retrogradation. Slightly higher moisture contents were observed for FRCs supplemented with proteins. The control was harder than FRCs enriched with 1%SPI and 2%MFC. The estimated shelf lives of FRCs made with 1% SPI and 2% MFC were higher than the control. The type and amount of various proteins dominated the quality of enriched FRCs. Practical applications The addition of protein to rice flour-based food products improves both the nutritional and physical qualities of the product since many gluten-free products have poor sensory characteristics. Our findings can be used to guide the producers of fermented rice cakes to choose a reasonable additive to improve the quality of the product and extend their shelf life, and are relevant to food product development and processing research, especially the development of gluten-free products.

Effects of the molecular weight and protein and sulfate content of Chlorella ellipsoidea polysaccharides on their immunomodulatory activity

We investigated the effects of the protein and sulfate content, as well as the molecular weight (Mw), of green alga Chlorella ellipsoidea polysaccharides on their immunomodulatory activity. The deproteinized (DP1-3), desulfated (DS1-3), and hydrolyzed (DH1-3) derivatives of C. ellipsoidea polysaccharides were prepared by enzymatic hydrolysis, desulfation, and acid hydrolysis, respectively, of differing durations, resulting in preparations containing various amounts of proteins (2.41%–8.97%), sulfates (1.36%–4.89%), and Mw (51.5–193.4kDa). The DH1-3-induced production of nitric oxide (NO) by RAW264.7 cells, decreased as the Mw of DH1-3 decreased. In addition, the sulfate content and Mw of DS1-3 affected the release of NO. However, lower protein content did not affect DP1-3-induced NO release and cytokine mRNA expression in RAW264.7 cells. Based on a multiple regression analysis of the effects of protein content, sulfate content, and Mw, on NO release, we found that Mw was a key factor for the stimulation of RAW264.7 cells, as it affected cytokine production, and activation of the nuclear factor-kappa B (NF-κB) and mitogen-activated protein kinase (MAPK) pathways. Therefore, the Mw of C. ellipsoidea polysaccharides played an important role in their immunomodulatory activities.

Serum amyloid A self-assembles with phospholipids to form stable protein-rich nanoparticles with a distinct structure: A hypothetical function of SAA as a "molecular mop" in immune response.

Serum amyloid A (SAA) is an acute-phase protein whose action in innate immunity and lipid homeostasis is unclear. Most circulating SAA binds plasma high-density lipoproteins (HDL) and reroutes lipid transport. In vivo SAA binds existing lipoproteins or generates them de novo upon lipid uptake from cells. We explored the products of SAA-lipid interactions and lipoprotein remodeling in vitro. SAA complexes with palmitoyl-oleoyl phosphocholine (POPC) were analyzed for structure and stability using circular dichroism and fluorescence spectroscopy, electron microscopy, gel electrophoresis and gel filtration. The results revealed the formation of 8-11nm lipoproteins that were∼50% α-helical and stable at near-physiological conditions but were irreversibly remodeled at Tm∼52°C. Similar HDL-size nanoparticles formed spontaneously at ambient conditions or upon thermal remodeling of parent lipoproteins containing various amounts of proteins and lipids, including POPC and cholesterol. Therefore, such HDL-size particles formed stable kinetically accessible structures in a wide range of conditions. Based on their size and stoichiometry, each particle contained about 12 SAA and 72 POPC molecules, with a protein:lipid weight ratio circa 2.5:1, suggesting a structure distinct from HDL. High stability of these nanoparticles and their HDL-like size suggest that similar lipoproteins may form in vivo during inflammation or injury when SAA concentration is high and membranes from dead cells require rapid removal. We speculate that solubilization of membranes by SAA to generate lipoproteins in a spontaneous energy-independent process constitutes the primordial function of this ancient protein, providing the first line of defense in clearing cell debris from the injured sites.

Improved Performance of Recombinant Protein A Immobilized on Agarose Beads by Site-Specific Conjugation.

Protein A affinity adsorbent with high antibody-binding capacity plays a prominent part in the purification of biopharmaceuticals to decrease the manufacturing costs. We describe a site-specific covalent conjugation strategy for protein A to immobilize on agarose beads. Recombinant protein A, which has one cysteine introduced at the C terminus through genetic engineering technology, was immobilized site-specifically on maleimide-functionalized agarose beads by the thiol–maleimide reaction. As a comparison, the recombinant protein A was randomly immobilized on the aldehyde-functionalized agarose beads via free amino groups on the protein surface. The site-specific conjugation of recombinant protein A on the agarose beads was validated through the assay of free SH groups on the adsorbents using the Ellman’s reagent. Adsorbents containing various amounts of protein A were used to adsorb antibody from human plasma. Analysis of immunoturbidimetry showed that the adsorbed fractions contained the 90.1% IgG, 4.2% IgA, and 5.7% IgM. The maximal antibodies-binding capacities with static adsorption and dynamic adsorption were approximately 64 and 50 mg, respectively, per swollen gram for site-specifically conjugated adsorbent and 31 and 26 mg for randomly conjugated adsorbent. Remarkably, the high antibody-binding capacity for site-specifically conjugated adsorbent outperformed the existing commercial protein A Sepharose (approximately 30 mg/g). The orientation of a protein is crucial for its activity after immobilization, and these results demonstrate that the site-specifically conjugated protein molecule is in a functionally active form to interact with the antibody with weak steric hindrance. The proposed approach may be an attractive strategy to synthesize affinity adsorbents with high-binding capacity.

Structural characterization of sulfated arabinans extracted fromCladophora glomerataKützing and their macrophage activation

Water-soluble sulfated heteropolysaccharides were extracted from Cladophora glomerata Kützing and fractionated by ion-exchange chromatography, which yielded two subfractions, F1 and F2. The crude and fractionated polysaccharides (F1 and F2) mostly consisted of carbohydrates (62.8-74.5%) with various amounts of proteins (9.00-17.3%) and sulfates (16.5-23.5%), including different levels of arabinose (41.7-54.4%), galactose (13.5-39.0%), glucose (0.80-10.6%), xylose (6.84-13.4%), and rhamnose (0.20-2.83%). Based on the size exclusion chromatography (SEC) profiles, the crude and fractions mainly contained one peak with shoulders having molecular weight (Mw) ranges of 358-1,501×10(3). The F1 fraction stimulated RAW264.7 cells to produce considerable amounts of nitric oxide and cytokines compared to the crude and F2 fraction. The backbone of the most potent immunostimulating fraction (F1) was α-(1→4)-L-arabinopyranoside with galactose and xylose residues as branches at O-2 position, and sulfates mainly at O-2 position as well.

Recombinant Protein A Immobilized on Cross-linked Cellulose Microspheres for Immunoglobulin G Adsorption from Human Plasma

Cross-linked cellulose microspheres (CL-CMs) were successfully prepared using an inverse crosslinking suspension method from a cellulose solution with sodium hydroxide/urea aqueous solution as a solvent and epichlorohydrin as the crosslinker. The effects of epichlorohydrin content on the appearance and dispersity, average pore volume, moisture content, and wet real density of CL-CMs were studied. The microspheres presented a good spherical shape and porous surface structure. After activation with NaIO4, the recombinant protein A was immobilized onto the surface of CL-CMs to form an immunoadsorbent. Adsorbents containing various amounts of protein A were applied to adsorb immunoglobulin G (IgG) from human plasma. The maximum IgG adsorption capacities with static adsorption and dynamic adsorption were 23 and 13 mg, respectively, per gram of CL-CMs carrying 6.8 mg of recombinant protein A. Therefore, CL-CMs immobilized with recombinant protein A have great potential for application in the field of blood purification.

Structural characteristics of polysaccharides extracted from Cladophora glomerata Kützing affecting nitric oxide releasing capacity of RAW 264.7 cells

Abstract The effect of molecular structures of sulfated polysaccharide (NF1) isolated from Cladophora glomerata Kutzing on the NO releasing capacity was investigated. It was possible to obtain the NF1 derivatives having various amounts of proteins (2.55-8.50%) and sulfates (6.88-13.1%) as well as different Mw (141-610 × 103 g/mol), which enabled to investigate the effects of various proteins, sulfates and Mw of NF1 on the NO releasing capacity from RAW 264.7 cells. The activity was lost after desulfation of the polysaccharides and moreover slightly increased NO releasing capacity after oversulfation of NF1 polysaccharides with the degree of sulfation (DS, 3.70). Suggesting that the sulfate groups were essential to activate NF1 polysaccharides are key factors to regulate the immunomodulatory activities.

Characterization and immunomodulatory activities of polysaccharides from Spirogyra neglecta (Hassall) Kützing.

Sulfated polysaccharides (SP) isolated from freshwater green algae, Spirogyra neglecta (Hassall) Kützing, and fractionated SPs were examined to investigate their molecular characteristics and immunomodulatory activity. The crude and fractionated SPs (F1, F2, and F3) consisted mostly of carbohydrates (68.5-85.3%), uronic acids (3.2-4.9%), and sulfates (2.2-12.2%) with various amounts of proteins (2.6-17.1%). D-galactose (23.5-27.3%), D-glucose (11.5-24.8%), L-fucose (19.0-26.7%), and L-rhamnose (16.4-18.3%) were the major monosaccharide units of these SPs with different levels of L-arabinose (3.0-9.4%), D-xylose (4.6-9.8%), and D-mannose (0.4-2.3%). The SPs contained two sub-fractions with molecular weights (Mw) ranging from 164 × 10(3) to 1460 × 10(3) g/mol. The crude and fractionated SPs strongly stimulated murine macrophages, producing considerable amounts of nitric oxide and various cytokines via up-regulation of their mRNA expression by activation of nuclear factor-kappa B and mitogen-activated protein kinases pathways. The main backbone of the most immunoenhancing SP was (1→3)-L-Fucopyranoside, (1→4,6)-D-Glucopyranoside, and (1→4)-D-Galactopyranoside.

Structure-activity relationships of sulfated glycoproteins from Codium fragile on nitric oxide releasing capacity from RAW264.7 Cells.

The effects of sulfate and protein contents as well as molecular weights of the sulfated glycoproteins (NF2) from Codium fragile on the immunomodulation were systematically investigated. The obtained NF2 derivatives displayed various amounts of proteins (2.3-8.7 %) and sulfates (4.3-8.1 %) as well as different molecular weights (47.3-128.0 × 10(3) g/mol). NF2 was not able to stimulate RAW264.7 cells to release NO without its protein moiety, which was essential to activate NF-κB pathway through the degradation and phosphorylation of IκB-α and the subsequent translocation of p65/p50 complex in the cell nucleus. In addition, the proteins in NF2 were required to trigger MAPK pathway for the phosphorylation of ERK1/2, p38, and JNK1/2 as well as the nuclear translocation of c-JUN and c-FOS. However, the protein moiety itself could not activate RAW264.7 cells, thus the complex formation of the polysaccharide and protein moieties in NF2 was pivotal to stimulate macrophage cells.

Structural Effects of Sulfated-Glycoproteins from Stichopus japonicus on the Nitric Oxide Secretion Ability of RAW 264.7 Cells.

The effect of various levels of proteins, sulfates, and molecular weight (Mw) of a sulfated-glycoprotein (NF3) from a sea cucumber, Stichopus japonicus, on nitric oxide (NO) releasing capacity from RAW 264.7 cells was investigated. The NF3 derivatives had various amounts of proteins (4.8~11.2%) and sulfates (6.8~25.2%) as well as different Mw (640.3×103~109.2×103 g/mol). NF3 was able to stimulate RAW 264.7 cells to release NO with lower protein contents, indicating that the protein moiety was not an important factor to stimulate macrophages. On the other hand, the NO inducing capacity was significantly reduced with decreased levels of sulfates and Mw, implying that sulfates and Mw played a pivotal role in activating RAW 264.7 cells. It was not clear why sulfates and a certain range of Mw were essential for stimulating macrophages. It appeared that certain levels of sulfates and Mw of sulfated-glycoproteins were required to bind to the surface receptors on RAW 264.7 cells.

Role of prothrombin complex concentrate in perioperative coagulation therapy.

Prothrombin complex concentrate (PCC) is a term to describe pharmacological products that contain lyophilized, human plasma-derived vitamin K-dependent factors (F), FII, FVII, FIX, FX, and various amounts of proteins C and S. PCCs can be rapidly reconstituted in a small volume (20 ml for about 500 international units (IU)) at bedside and administered regardless of the patient’s blood type. PCCs are categorized as 4-factor PCC if they contain therapeutic amounts of FVII, and 3-factor PCC when FVII content is low. In addition, activated PCC which contains activated FVII and FX with prothrombin is available for factor VIII bypassing therapy in hemophilia patients with inhibitors. Currently, 4-factor PCC is approved for the management of bleeding in patients taking warfarin, but there has been increasing use of various PCCs in the treatment of acquired perioperative coagulopathy unrelated to warfarin therapy and in the management of bleeding due to novel oral anticoagulants. There is also an ongoing controversy about plasma transfusion and its potential hazards including transfusion-related lung injury (TRALI). Early fixed ratio plasma transfusion has been implemented in many trauma centers in the USA, whereas fibrinogen concentrate and PCC are preferred over plasma transfusion in some European centers.In this review, the rationales for including PCCs in the perioperative hemostatic management will be discussed in conjunction with plasma transfusion.

Animal Protein and the Risk of Kidney Stones: A Comparative Metabolic Study of Animal Protein Sources

We compared the effect of 3 animal protein sources on urinary stone risk. A total of 15 healthy subjects completed a 3-phase randomized, crossover metabolic study. During each 1-week phase subjects consumed a standard metabolic diet containing beef, chicken or fish. Serum chemistry and 24-hour urine samples collected at the end of each phase were compared using mixed model repeated measures analysis. Serum and urinary uric acid were increased for each phase. Beef was associated with lower serum uric acid than chicken or fish (6.5 vs 7.0 and 7.3 mg/dl, respectively, each p <0.05). Fish was associated with higher urinary uric acid than beef or chicken (741 vs 638 and 641 mg per day, p = 0.003 and 0.04, respectively). No significant difference among phases was noted in urinary pH, sulfate, calcium, citrate, oxalate or sodium. Mean saturation index for calcium oxalate was highest for beef (2.48), although the difference attained significance only compared to chicken (1.67, p = 0.02) but not to fish (1.79, p = 0.08). Consuming animal protein is associated with increased serum and urine uric acid in healthy individuals. The higher purine content of fish compared to beef or chicken is reflected in higher 24-hour urinary uric acid. However, as reflected in the saturation index, the stone forming propensity is marginally higher for beef compared to fish or chicken. Stone formers should be advised to limit the intake of all animal proteins, including fish.

Protein intake in type 1 diabetes

Protein intake in type 1 diabetes

Protein Deposition and Its Effect on Bacterial Adhesion to Contact Lenses

Bacterial adhesion to contact lenses is believed to be the initial step for the development of several adverse reactions that occur during lens wear such as microbial keratitis. This study examined the effect of combinations of proteins on the adhesion of bacteria to contact lenses. Unworn balafilcon A and senofilcon A lenses were soaked in commercially available pure protein mixtures to achieve the same amount of various proteins as found ex vivo. These lenses were then exposed to Pseudomonas aeruginosa and Staphylococcus aureus. Following incubation, the numbers of P. aeruginosa or S. aureus that adhered to the lenses were measured. The possible effect of proteins on bacterial growth was investigated by incubating bacteria in medium containing protein. Although there was a significant (p < 0.003) increase in the total or viable counts of one strain of S. aureus (031) on balafilcon A lenses soaked in the lysozyme/lactoferrin combination, the protein adhered to lenses did not alter the adhesion of any other strains of P. aeruginosa or S. aureus (p > 0.05). Growth of S. aureus 031 (p < 0.0001) but not of P. aeruginosa 6294 was stimulated by addition of lysozyme/lactoferrin combination (2.8/0.5 mg/mL). Addition of lipocalin did not affect the growth of any strains tested (p > 0.05). Adsorption of amounts of lysozyme and lactoferrin or lipocalin equivalent to those extracted from worn contact lenses did not affect the adhesion of most strains of S. aureus or P. aeruginosa to lens surfaces.

Binding between Proteins and Cationic Spherical Polyelectrolyte Brushes: Effect of pH, Ionic Strength, and Stoichiometry

Cationic spherical polyelectrolyte brushes (SPBs) were synthesized by photoemulsion polymerization, consisting of a polystyrene core with a diameter around 80 nm and a poly(2-aminoethylmethacrylate hydrochloride) (PAEMH) shell with a thickness from 10 to 50 nm densely grafted on the core surface. The binding of various proteins onto SPBs was observed by turbidimetric titration, dynamic light scattering (DLS), zeta potential, and isothermal titration calorimetry (ITC). The binding, aggregation, and releasing of proteins by SPB can be tuned by modulating pH. The pH regions of binding for bovine serum albumin (BSA), β-lactoglobulin (BLG), and papain onto SPBs are markedly different and tunable by ionic strength and stoichiometry between protein and SPB. Binding energetics, affinity, and amount of various proteins onto cationic SPBs were determined by ITC. These findings lay the foundation for SPB applications in the protein purification and selective immobilization of different proteins, enzymes, and antibodies.