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This case report discusses how paraproteins interfere with multiple chemistry analyses and protocols to overcome such obstacles. A serum specimen containing two monoclonal IgA (llight chain) paraproteins is subjected to a battery of tests on three wet chemistry platforms - AU5800, Cobas Pure, and Alinityci; the results were compared with those on a Vitros 350/ ECiQ dry chemistry platform. Paraprotein interference was found to affect the bilirubins, inorganic phosphate, and iron, whose repeat runs were also found to be irreproducible. Dilution with normal saline also failed to produce a satisfactory effect. Deproteinization by polyethylene glycol and dilution of the specimen with a normal serum specimen were observed to produce desirable results. Interference by IgA paraprotein on measurement of the bilirubin, phosphate, and iron in the wet chemistry system can be mitigated either by deproteinization or by dilution with normal serum.

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BACKGROUND: Enamel conditioning with 37% phosphoric acid is the most common technique during orthodontic bracket bonding procedures. However, due to the repeated de-bonding of the orthodontic brackets during treatment, other methods were needed to condition the enamel surface and increase the bond strength. This study aimed to compare the effect of conditioning the enamel surface by sandblasting with aluminum oxide particles or 5.25% sodium hypochlorite gel in combination with acid etching compared to acid etching alone on shear bond strength (SBS). MATERIAL AND METHODS: One hundred eight extracted upper premolars were randomly divided into three groups according to the conditioning enamel surface method. After the first and second bonding of metal brackets, new metal brackets were bonded with a total-etching adhesive after enamel conditioning using different methods: acid etching only (37% phosphoric acid for 30 seconds) (AE group), sodium hypochlorite associated with acid etching (5.25% NaOCl gel for 60 seconds and then acid etching for 30 seconds) (NaOCl-AE group), and sandblasting associated with acid etching (sandblasting for five seconds and then acid etching for 30 seconds) (SB-AE group). The shear bond strengths of the brackets were tested with a universal testing machine. One-way analysis of variance (ANOVA) and Tukey's honestly significant difference (HSD) tests were used to detect significant differences in shear bond strength among groups at the third bonding. Repeated-measure ANOVA and Bonferroni's tests were used to detect significant differences in shear bond strength among the bonding attempts within each group. RESULTS: 5.25% sodium hypochlorite associated with the acid etching method produced significantly greater shear bond strength than sandblasting associated with acid etching and acid etching only methods at the third bonding (16.40 ± 5.80 MPa, 13.60.47 ± 6.40 MPa, and 9.90 ± 4.40 MPa, respectively; P < 0.001). However, there was no significant difference between the AE and SB-AE groups (P = 0.247). In addition, we found a significant decrease in the shear bond strength within each group after each bonding attempt. CONCLUSION: Conditioning the enamel surface with 5.25% sodium hypochlorite associated with acid etching produced greater bond strength than conditioning by sandblasting associated with acid etching and acid etching only at the third bonding. The bond strength of the metal bracket decreased with increasing bonding attempts, even with the application of enamel surface conditioning methods.

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Obtener una buena adhesión entre esmalte y bracket es un aspecto fundamental para el éxito del tratamiento en Ortodoncia. Algunos casos presentan desafíos en esta adhesión, especialmente cuando nos enfrentamos ante un esmalte con alteraciones como hipomineralizaciones, hipoplasias o fluorosis dental. Para sobreponer esta dificultad en la unión adhesiva se han propuesto diversas estrategias terapéuticas como es el uso de agentes desproteinizantes. El objetivo de esta revisión narrativa es describir el uso de hipoclorito de sodio como agente desproteinizante en dientes con alteraciones de esmalte para mejorar la adhesión en Ortodoncia. Se realizó una búsqueda bibliográfica en PubMed de los últimos 5 años. Se encontraron 116 artículos, de los cuales 23 cumplieron con los criterios requeridos y fueron seleccionados para la revisión. La desproteinización del esmalte con hipoclorito de sodio como paso previo al grabado ácido, es una estrategia útil en el proceso de cementación de aparatología de ortodoncia fija en dientes con alteraciones del esmalte. El uso de hipoclorito de sodio al 5,25 % es una alternativa de bajo co sto, no invasiva y eficiente para mejorar la fuerza de adhesión en pacientes con alteraciones del esmalte.

Obtaining good adhesion between enamel and bracket is a fundamental aspect for success in Orthodontics. Some cases present challenges in this adhesion, especially when we are faced with enamel with alterations such as hypomineralization, hypoplasia or dental fluorosis. To overcome this difficulty in adhesive bonding, various therapeutic strategies have been proposed, such as the use of deproteinizing agents. The objective of this study is to describe the use of sodium hypochlorite as a deproteinizing agent in teeth with enamel alterations to improve adhesion in Orthodontics. A bibliographic search was carried out in PubMed for articles within the last 5 years. In this study 116 articles were found, of which 23 met the required criteria and were selected for the review. Deproteinization of the enamel with sodium hypochlorite as a prior step to acid etching is an important stage in the cementation process of fixed appliances in orthodontics. The use of 5.25% sodium hypochlorite is a low-cost, non-invasive and efficient alternative to improve adhesion strength in patients with anomalies of tooth enamel.

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BACKGROUND: Interferences on chemistry and immunoassay results due to paraproteinemia may lead to erroneous diagnoses and treatment. Such interferences are difficult to recognize and even more difficult to deal with. This report describes 1 such case where multiple measurands were affected and how the interferant was overcome. CASE REPORT: Paraproteins present in an immunoglobulin (Ig)G-lambda multiple myeloma specimen interfered with results of total bilirubin, direct bilirubin, inorganic phosphate, iron, ferritin, and total thyroxine measured on 3 platforms: AU5800, Alinity ci, and cobas pure. Repeat testing upon dilution with normal saline or deproteinization by polyethylene glycol precipitation gave unsatisfactory results on some or all the affected measurands. Repeat testing after dilution of the interferant serum with a healthy serum corrected the anomalous results for all the affected measurands. CONCLUSION: Dilution of paraproteinemic serum with a healthy serum of known concentrations appears to be the most suitable method to negate the effects of paraproteinemic interferences.

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The aim of this study was to evaluate the 9-month clinical performance of different materials and treatment procedures in teeth with MIH in children, and to evaluate the effectiveness of Papacarie gel as a deproteinization agent. The study included 90 children (aged 8-15) who had 189 first permanent molars with MIH were restored randomly with 4 different materials/methods. Equia Forte HT (GC, Tokyo, Japan) was used in Group 1; In Group 2, G-eanial composite (GC, Tokyo, Japan) was used with a Fuji IX (GC, Tokyo, Japan) base; In Group 3 and Group 4, EverX Posterior (GC, Tokyo, Japan) base and G-eanial composite (GC, Tokyo, Japan) were used. In group 4, deproteinization was performed with Papacarie Duo gel (F&A, Sao Paulo, Brazil). The restorations were evaluated at 3-month intervals for 9 months using modified United States Public Health Service (USPHS) criteria. The overall recall rate was 94.1% for every 3-month clinical evaluation over 9 months. A total of 9 restorations were unsuccessful. Surface roughness of Group 1 was statistically different from all other groups in all control periods (p < 0.05). Marginal adaptation of Group 2 was found to be significantly different from Groups 3 and 4 at the both of 6th and 9th month controls. There was no significant difference between the groups in terms of retention, color match, marginal discoloration and secondary caries in all control months. Restoration of MIH with Equia Forte HT is almost as successful as composites. The use of dentin replacement materials instead of glass ionomer cements as a base in composite restorations shows better results. Papacarie deproteinization showed similar success with other composite groups. This study was the first clinical study in which Papacarie was used for deproteinization in teeth with MIH and will thus contribute to the literature.

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Suppressed ion chromatography with perchloric acid deproteinization was developed for the determination of phosphorus in commercially available milk. Although the perchloric acid deproteinization method is widely used in the medical field, it sees limited application in the food industry. Herein, the concentration of perchloric acid and hydrolysis conditions were examined, specifically regarding perchloric acid deproteinization, which was used as a deproteinization method in this study. The calibration curve constructed from the peak area of orthophosphoric acid (monohydrogen phosphate ion: HPO42-) was linear, with a correlation coefficient of 0.999. The relative standard deviation of the peak area of 50 mg/L of HPO42- from six replicates was 0.35%. The detection and quantitative limits of HPO42-, calculated from its signal-to-noise ratio were 0.033 mg/L and 0.100 mg/L, respectively. The proposed method was applied to the analysis of phosphorus in commercially available milk. Perchloric acid deproteinization has proved to be useful in the food industry.

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The chitin and chitosan biopolymers are extremely valuable because of their numerous industrial and pharmacological uses. Chitin and chitosan were extracted from the exoskeleton of Periplaneta americana (cockroaches) and termites using various acid and alkali techniques. The extraction process involves an initial demineralization step, during which integument dry powder was subjected to 500 mL (2.07 mol/L) of concentrated HCl at 100 degrees Celsius for 30 min, followed by meticulous rinsing with distilled water to restore the pH to its baseline. Deproteinization was conducted at 80 degrees Celsius using 500 mL (1 mol/L) of NaOH solution, which was repeated for 24 h. A total of 250 mL (0.06 mol/L) of NaOH was added at 100 degrees Celsius for 4 h to obtain chitosan, followed by extensive washing and subsequent drying. FTIR analysis was used to identify the functional groups in Periplaneta americana and termites. The crystallinity of these biopolymers, which have a face-centered cubic structure, was determined by X-ray diffraction analysis. This study assessed the analgesic properties of chitin and chitosan via an acetic-acid-induced writhing test in mice, revealing a significant reduction in writhing behavior following the chitin and chitosan extract. Notably, chitin exhibits the highest degree of analgesic activity compared to chitosan. Both chitin and chitosan show anti-inflammatory effects, with chitosan absorbing proton ions at sites of inflammation, while chitin effectively inhibits ear edema and elicits an analgesic response in mice. Furthermore, the present study revealed antipyretic activity, with termite chitin demonstrating the most significant effect at a concentration of 500 µL/mL, followed by chitosan and chitin at 100 µL/mL. These findings indicate the potential of using chitin and chitosan derived from termites and Periplaneta americana as natural anti-inflammatory compounds, implying prospective uses in anti-inflammatory, antipyretic, and analgesic capabilities.

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The physicochemical properties of grafting materials affect the quality of the osteointegration, resorption rate, and the new bone (NB) formation. This study assessed the physicochemical properties and integration of a low temperature deproteinized bovine bone xenograft (BBX), referred to as optimized MoaBone® (OMB). This novel BBX was physiochemically characterized both pre and post chemical bleaching and sterilization by gamma irradiation. OMB was compared to two commercial BBX; Bio-Oss® (BO) and MoaBone® (MB) using a rabbit cranial model. Residual graft and NB were quantified using histology and micro-computed tomography. Results showed that chemical treatment and gamma irradiation had limited effect on the surface texture. A significant decrease in the collagen content was detected post chemical treatment and in the carbonate content post gamma irradiation. There was no evidence of inflammatory infiltrate, necrosis, or connective tissue encapsulation, and a significant increase of NB in all grafted sites as compared to untreated defects could be observed. However, there was no statistically significant difference between the grafted sites. We conclude that chemical treatment and terminal sterilization strongly impact the final graft's properties. OMB graft showed equivalence with BO for in vivo bone formation and potentially results in lower levels of graft retention.

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OBJECTIVES: To evaluate the effect of bromelain associated with Biosilicate on the bond strength (BS) of a universal adhesive system to sound (SD) and caries-affected dentin (CAD), and on the proteolytic activity. MATERIALS AND METHODS: Cavities were prepared in 360 molars, half submitted to cariogenic challenge. Teeth were separated into groups (n=20): Control-No treatment; CHX-0.12% chlorhexidine; NaOCl-5% sodium hypochlorite; Br5%-5% bromelain; Br10%-10% bromelain; Bio-10% Biosilicate; NaOClBio-NaOCl+Bio; Br5%Bio-Br5%+Bio; Br10%Bio-Br10%+Bio. Following treatments, the adhesive system was applied, and cavities were restored. Samples were sectioned into sticks and stored at 37 °C for 24 h, 6 months, and 1 year. Microtensile BS (2-way ANOVA, Bonferroni's test, α=0.05), fracture patterns (SEM), and adhesive interfaces (TEM) were evaluated. Bacterial collagenase assay and in situ zymography were performed. RESULTS: In CAD, Br10% presented higher BS (p=0.0208) than Br5%Bio. Br5% presented higher BS (p=0.0033) after 6 months than after 24 h; and association of treatments, higher BS (p<0.05) after aging than after 24 h. Mixed fractures were the most prevalent. Association of treatments promoted a more uniform hybrid layer with embedded Bio particles. Experimental groups presented lower (p<0.0001) relative fluorescence units than Control. Bromelain, associated or not with Bio, showed collagenolytic degradation. CONCLUSIONS: Bromelain associated with Biosilicate did not affect the BS to SD. In CAD, Br5%Bio decreased immediate BS but had no long-term influence. This association decreased the proteolytic activity. CLINICAL RELEVANCE: Bromelain and Biosilicate may enhance the longevity of adhesive restorations by inhibiting endogenous proteases.

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This study evaluates the effect of the deproteinization agents hypochlorous acid and sodium hypochlorite upon the bonding of the two different pit and fissure sealant, self-adhesive flowable composites with the enamel. Thirty-six third molars were randomly divided into six different groups. The groups were formed as follows: Group 1: 37% phosphoric acid + VertiseTM Flow; Group 2: 200 ppm hypochlorous acid + 37% phosphoric acid VertiseTM Flow; Group 3: 5.25% sodium hypochlorite + 37% phosphoric acid + VertiseTM Flow; Group 4: 37% phosphoric acid + Constic; Group 5: 200 ppm hypochlorous acid + 37% phosphoric acid + Constic; Group 6: 5.25% sodium hypochlorite + 37% phosphoric acid + Constic. In each group, samples were obtained that were rectangular prisms in shape (n = 12). Groups to which a deproteinization agent was applied (Groups 2, 3 and 5, 6) showed statistically higher microtensile bonding strength than Group 1, Group 4. There was no statistically significant difference in terms of microtensile bonding strength values between the Groups 3 and the Group 6. The study found that the groups to which deproteinization agents were applied had statistically higher microtensile bonding strength values compared with those groups to which acid and fissure sealants were applied. In this study, it was concluded that the use of fissure-sealing self-adhesive flowable composites after acid application to permanent tooth enamel provides an acceptable bond strength given the limitations of in vitro studies. In line with the results obtained, it was observed that in addition to the removal of the inorganic structure with the application of acid, the removal of the organic structure with the use of deproteinization agent increased the bond strength to the enamel.

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The study aimed to develop an effective and eco-friendly enzymatic process to extract carotenoproteins from shrimp waste. The optimization of enzymatic hydrolysis conditions to maximize the degree of deproteinization (DDP) of carotenoprotein from shrimp head waste (SHW) and shrimp shell waste (SSW) was conducted separately using the Box-Behnken design of response surface methodology (RSM). To achieve a maximum DDP of 92.32% for SSW and 96.72% for SHW, the optimal hydrolysis conditions were determined as follows: temperature (SSW: 53.13 °C; SHW: 45.90 °C), pH (SSW: 7.13; SHW: 6.78), time (SSW: 90 min; SHW: 61.18 min), and enzyme/substrate ratio (SSW: 2 g/100 g; SHW: 1.18 g/100 g). The carotenoprotein effluent obtained was subjected to spray drying and subsequently assessed for color, nutritional, and functional characteristics. The carotenoprotein from shrimp shell (CpSS) contained a higher essential amino acid score than carotenoprotein from shrimp head (CpSH). CpSS had a higher whiteness index of 82.05, while CpSH had 64.04. Both CpSS and CpSH showed good functional properties viz solubility, emulsion, and foaming properties. The maximum solubility of CpSH and CpSS was determined to be 92.94% and 96.48% at pH 10.0, respectively. The highest emulsion capacity (CpSH: 81.33%, CpSS: 70.13%) and stability (CpSH: 57.06%, CpSS: 63.05%) were observed at 3% carotenoprotein concentration. Similarly, the highest values of foaming capacity (CpSH: 27.66%, CpSS: 105.5%) and stability (CpSH: 23.83%, CpSS: 105.33%) were also found at the same 3% carotenoprotein concentration. In conclusion, the carotenoproteins obtained from shrimp waste showed favorable attributes in terms of color, amino acid composition, and functional properties. These findings strongly suggest the potential applicability of CpSS and CpSH as valuable resources in various domains. CpSS, with its higher whiteness index, greater amino acid content, and superior functional characteristics, may find suitability as functional ingredients in human food products. Conversely, CpSH could be considered for incorporation into animal feed formulations.

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Management of crustacean shell waste (SW) through an eco-friendly technique is an environmental obligation to control pollution. The present study showed a novel approach through the simultaneous application of proteolytic and chitinolytic bacteria to effectively degrade unprocessed crustacean SW. For this, the bacteria with concurrent chitinolytic and proteolytic activity (Bacillus subtilis, Priestia megaterium, or Bacillus amyloliquefaciens) were applied either alone or in combination with one proteolytic strain (Paenibacillus alvei) in the unprocessed lobster, crab, and shrimp SW. The method degraded the shells with high deproteinization (> 90%) and demineralization efficiency (> 90%). The degradation was confirmed through scanning electron microscopy. The highest weight loss achieved with shrimp, crab, and lobster shells was 93.67%, 82.60%, and 83.33%, respectively. B. amyloliquefaciens + P. alvei combination produced the highest weight loss in crab and lobster SW, whereas all combinations produced statistically similar weight loss in shrimp SW. There was a concurrent production of N-acetyl glucosamine (up to 532.89, 627.87, and 498.95 mg/g of shrimp, lobster, and crab shell, respectively, with P. megaterium + P. alvei and B. amyloliquefaciens + P. alvei in all SW) and amino acids (4553.8, 648.89, 957.27 µg/g of shrimp, lobster, and crab shells, respectively with B. subtilis + P. alvei in shrimp and B. amyloliquefaciens + P. alvei in crab and lobster). Therefore, it is concluded that, for the first time, efficient degradation of crustacean shell waste was observed using chitinolytic and proteolytic bacterial fermentation with the obtention of byproducts, providing a basis for further application in SW management.

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Natural Rubber (NR), extracted from Hevea brasiliensis rubber trees, is a biocompatible biopolymer with properties that support in the tissue repair process. However, its biomedical applications are limited due to the presence of allergenic proteins, hydrophobicity, and unsaturated bonds. To overcome these limitations and contribute to the development of new biomaterials, this study aims to deproteinize, epoxidize, and subject NR to copolymerization by grafting with hyaluronic acid (HA), which is widely recognized for its bioactive properties in the medical field. The deproteinization, epoxidation, and graft copolymerization through the esterification reaction were confirmed by Fourier Transform Infrared Spectroscopy and Hydrogen Nuclear Magnetic Resonance Spectroscopy analysis. Thermogravimetry and Differential Scanning Calorimetry demonstrated that the grafted sample exhibited a lower degradation rate and a higher glass transition temperature, indicating strong intermolecular interactions. Moreover, contact angle measurement revealed that the grafted NR exhibited a high hydrophilic character. The results obtained suggest the formation of a novel material with great potential for application in biomaterials involved in tissue repair processes.

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Unless better measures are put in place to address the environmental and social impacts emanating from the huge waste generated from sea food processing industries; 'tragedy of the commons' is inevitable. Needless to re-emphasise the enormous contributions of aquaculture as the perfect substitute to capture fisheries which has been proven unsustainable. Be that as it may, the huge amount of bio-waste produced could be transformed into useful products such as chitin and chitosan with far reaching applications. Chitin and chitosan have been consistently processed from many sources following the traditional chemical sequence of Demineralization (DM), Deproteinization (DP), Decolouration (DC) and Deacetylation (DA). In this study, this method was re-ordered, resulting to 4 sequences of chemical processes. HCl, NaOH, ethanol (97%) and NaOH (50%) were used for DM, DP, DC and DA respectively. The results of this study showed that better chitin (23.99 ± 0.61%) and chitosan (15.17 ± 1.69%) yields were obtained from sequence four (SQ4) following the order of DC-DM-DP-DA. In addition, physicochemical properties such as DDA (80.67 ± 2.52%) and solubility (66.43 ± 2.61%) were significantly higher (p ≤ 0.05) in SQ4 thereby making the obtained product suitable for use as coagulant and flocculant in wastewater treatment. Results of FTIR, XRD and SEM of the study proved that the resultant product exhibited the characteristic nature of chitosan with porous and fibril nature. In the analysis of the physical properties of chitosan obtained from bio-waste of Macrobrachium rosenbergii, the high Carr's index (CI) and low bulk as well as tapped densities were an indication that the chitosan produced in this study had poor flowability and compressibility, thereby making it unfit for application in pharmaceutical industries.

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OBJECTIVE: To investigate the effect of enamel deproteinization and air abrasion on shear bond strength (SBS), adhesive remnant index (ARI) scores, and surface topography when bonding orthodontic brackets to fluorosed enamel. MATERIALS AND METHODS: The sample included 90 fluorosed and 30 normal premolars divided into four groups: group I (fluorosed premolars subjected to air abrasion before acid etching), group II (fluorosed premolars subjected to deproteinization before acid etching), group III (fluorosed premolars; control for groups I and II), and group IV (normal premolars; control for group III). Bonding procedures included etching with 37% phosphoric acid, priming with TransbondTM XT primer (3M Unitek, Monrovia, CA, USA), and application of TransbondTM XT adhesive paste (composite; 3M Unitek, Monrovia, CA, USA). Air abrasion was done using 50 µm aluminum oxide particles under 0.28 MPa pressure for 5 s with the micro-etcher held at a distance of 10 mm. Deproteinization was done for 60 s with 5% sodium hypochlorite (NaOCl). RESULTS: Fluorosed premolars subjected to deproteinization showed the lowest (median = 6.57 MPa) SBS among the four groups, followed by 8.14, 8.90, 8.14 MPa for groups I, III, and IV respectively. ARI scores were significantly different between the four groups (p = 0.006). Fluorosed enamel etched after air abrasion or deproteinization with NaOCl showed a predominance of type 4 etching pattern with some areas appearing unetched. CONCLUSIONS: Shear bond strength of all groups was within the 6-8 MPa acceptable range for orthodontic purposes. Fluorosed premolars subjected to deproteinization showed the lowest values. Further studies are recommended to scrutinize the deproteinization technique.

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The polysaccharides derived from various deproteinization methods were prepared from Flos Sophorae Immaturus (FSI) to investigate the prebiotic efficacy of Lactobacillus fermentum (L.f ). The implications of polysaccharides from FSI (PFSI) gained after purification performed by non-deproteinization and different deproteinization processes (Savage method, papain method, and TCA method) via one-factor optimization were firstly investigated for the influences on the growth of L.f. The utilization of carbohydrate sources and the synthesis of protein and lactate during its growth were analyzed, as well as the variations of LDH, SOD, and GSH- Px enzyme dynamics. The results showed that the one-factor optimization of the deproteinization process with the protein removal rate and polysaccharide retention rate as the indexes led to the optimal methods of the Sevage method with 5 elution times, papain method with 80 U/mL concentration, and TCA method with 2.5 ratio, respectively. In addition, the PFSI obtained with or without deproteinization purification had a certain effect on promoting L.f proliferation. Moreover, the PFSI gained by the third deproteinization purification, at a concentration of 10 g/L, significantly elevated L.f biomass and growth rate compared with the blank control, and the utilization of reducing sugars and the synthesis of protein and lactic acid were higher than the control (P < 0.05); improved LDH, SOD, and GSH-Px activity in L.f (P < 0.05), and the TCA method could be effectively applied to eliminate the proteins affecting FSI in probiotics, and PFSI may be a potentially beneficial prebiotic and intestinal reinforcer.

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Amino acids play an important role in metabolism. Comprehensive analytical validation of an assay for the concurrent measurement of a large number of amino acids in dogs is lacking, which precludes its usefulness in a clinical setting. Amino acids are often measured in plasma or whole blood. However, serum is commonly used for gastrointestinal diagnostic testing in dogs and is therefore convenient to use. This study aimed to analytically validate an assay for the concurrent measurement of amino acids in dog serum and to evaluate differences in amino acid concentrations in whole blood, plasma, and serum in dogs. Analytical validation of the assay (Biochrom 30+ Amino Acid Analyzer) was performed on fresh or banked serum samples from dogs. Whole blood, plasma, and serum from 36 healthy dogs were analyzed, and concentrations of the three sample types were compared. The assay was demonstrated to be precise, reproducible, accurate, linear, and stable for the measurement of the majority of compounds detected in dog serum. Cystine, glutamic acid, and ethanolamine were shown to be unstable at conditions commonly encountered in clinical settings. Significant differences in concentrations were identified between whole blood, plasma, and serum for 33 of 42 compounds. Amino acid profiles in serum and plasma were more similar to each other than to those in whole blood. While some amino acids are present in similar concentrations in whole blood, plasma, and serum, others are highly dependent on the type of biofluid, and measurements warrant strict adherence to sample type-based reference intervals.

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Nano-hydroxyapatite (nHAp) as a bio-filler used in PLA composites was prepared from fish by acid deproteinization (1DP) and a combination of acid-alkali deproteinization (2DP) followed by alkali heat treatment. Moreover, the PLA/nHAp composite films were developed using solution casting method. The mechanical and thermal properties of the PLA composite films with nHAp from different steps deproteinization and contents were compared. The physical properties analysis confirmed that the nHAp can be prepared from fish scales using both steps deproteinization. 1DP-nHAp showed higher surface area and lower crystallinity than 2DP-nHAp. This gave advantage of 1DP-nHAp for use as filler. PLA composite with 1DP-nHAp gave tensile strength of 66.41 ± 3.63 MPa and Young's modulus of 2.65 ± 0.05 GPa which were higher than 2DP-nHAp at the same content. The addition of 5 phr 1DP-nHAp into PLA significantly improved the tensile strength and Young's modulus. PLA composite solution with 1DP-nHAp at 5 phr showed electrospinnability by giving continuous fibers without beads.

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Natural Rubber Field Latex (NRFL) allergens restrict its use in some markets due to health-threatening allergic reactions. These molecules are proteins that are related to asymptomatic sensitization and hypersensitivity mediated by immunoglobulin E (IgE). Although NRFL allergens have been investigated since the 1980s, there are still gaps in knowledge regarding the development of deproteinized natural rubber (DPNR). Therefore, in this study, the deproteinization of NRFL from the lower basin of the Cauca River, Antioquia-Colombia was evaluated using eight systems. The highest removal value was 84.4% and was obtained from the treatment containing SDS (Sodium dodecyl sulfate), Urea, and Ethanol. It was also possible to determine that at high concentrations of SDS, removal percentages higher than 70% are reached. On the other hand, all deproteinizing systems decreased NRFL Zeta potentials without self-coagulation, suggesting enhanced colloidal stability in DPNR latex. On the other hand, the bibliometric analysis presented technological advances in DPRN through different parameters and bibliometric networks. The analysis presented makes an important contribution from the bibliometric approach that could be positive for the development of research on DPNR.

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Residual protein in chitosan-based biomaterials may cause inflammation, allergy, and immune rejection after surgery, impeding their clinical application. Facile production of chitosan with ultra-low protein content (residual protein <0.2 %) is yet to be addressed. Herein, we proposed a one-step method for preparing chitosan with residue protein content <0.2 % by using hydrogen peroxide and sodium dodecyl sulfate, which is simple, time-saving, cost-effective, and acid/alkali-free. Notably, the molecular weight of chitosan can be reduced simultaneously. The effects of experimental parameters (i.e. hydrogen peroxide concentration (0.01 %-1 %), SDS concentration (5 %-20 %), and reaction temperature (50 °C-70 °C)) on the protein removal and molecular weight decrease were systematically analyzed by response surface methodology. The results show that temperature and H2O2 concentration are the main parameters affecting the deproteinization of chitosan. Further characterizations on the resulting ultra-low protein residue chitosan revealed unchanged chemical structure, enhanced crystallinity, and reduced thermal stability. The proposed one-step deproteination method may have great potential for industrial mass production of ultra-low protein residue chitosan.

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