High-speed sintered bodies of 5Y zirconia were evaluated by density measurements, translucency measurements, three-point flexural and fracture toughness tests, X-ray diffraction (XRD), and scanning electron microscopy (SEM). High-speed sintering reduced the translucency and mechanical properties of 5Y zirconia. XRD and SEM observation results clarified that these reductions were due to the change in crystal phase composition and to the increase in residual pores, respectively, both resulting from high-speed sintering. Moreover, in high-speed sintering, as the thickness of the specimen increased, the number and size of internal pores increased, and the translucency and strength decreased. The threshold value for avoiding a reduction in translucency and mechanical properties was found to lie at ~4.4 mm. From the above results, it was concluded that 5Y zirconia is not suitable for high-speed sintering applications.High-speed sintering of zirconia has become essential to single-visit dental prosthetic treatments. This important prosthetic dentistry technique demands a translucent material tougher than porcelain. Previous studies on high-speed sintered zirconia did not take heat and material thickness into consideration. We evaluated pre-sintered specimen thickness and the effect of high-speed sintering on the properties of 5 mol% Y Of these stabilizers, Y2O3 is used in most dental zirconia. The stabilizer concentration greatly influences the properties of zirconia. In general, the higher the concentration of the stabilizer, the higher the translucency, and conversely, the lower the mechanical properties [Dental prostheses are commonly produced from zirconia due to its high bending strength, fracture toughness, chemical stability, radiopacity, and biocompatibility ,2. The eoperties ,5. Howevoperties ,7 reportoperties ,7, yttri2O3-stabilized zirconia (3Y zirconia), 4 mol% Y2O3-stabilized zirconia (4Y zirconia), and 5 mol% Y2O3-stabilized zirconia (5Y zirconia), are used most commonly. Selection is dependent on the intended use. For example, 5Y zirconia, which has high translucency, is used where aesthetic demands are high, such as in anterior teeth, while 3Y zirconia, which has excellent mechanical properties, is used where heavy loads are applied such as in long span bridges [In the field of prosthodontics, 3 mol% Y bridges ,9.Zirconia dental prostheses are fabricated by employing computer-aided design and computer-aided manufacturing (CAD/CAM) systems. Since zirconia sintered bodies are difficult to process, they are generally produced after processing semi-sintered zirconia into the desired prosthesis shape and then sintering it for 6 to 10 h [In recent years, several manufacturers have released furnaces for high-speed sintering. CEREC Speedfire (Dentsply Sirona) is a well-known example. This sintering furnace can densify zirconia with 30 min of microwave heating; so, it enables the completion of a zirconia prosthetic treatment within a single dental visit (One Visit Treatment) ,12. As mIt is well known that sintering schedules such as heating rate and holding time affect the translucency, relative density, particle size, and mechanical properties of sintered ceramics. Therefore, it is important to investigate the effect of high-speed sintering on the properties of dental zirconia. In fact, there are several studies on high-speed sintering effects on the properties of zirconia ,14,15,16Jansen et al.  investigHowever, in these studies, the effect of high-speed sintering could not be accurately evaluated because the sintering temperature of conventional and high-speed sintering often differs. Furthermore, the effect of high-speed sintering on the crystal phase of zirconia and its effect on the properties of zirconia were not fully discussed. In addition, there is a lack of knowledge of the reliability of thick dental prostheses because the effect on the properties of zirconia of the test piece thickness during sintering has not been discussed.The aim of this study is to evaluate the effects of CEREC Speedfire high-speed sintering on the translucency and mechanical properties of 5Y zirconia at various specimen pre-sintered thicknesses, and to clarify the causes from crystal structure and microstructure assessments.Specimen dimensions and fabrication procedures are summarized in Zpex Smile  were used as raw materials for 5Y zirconia containing 0.05 wt% of alumina. The raw material was press-molded by a uniaxial press molding machine  to obtain a block having a diameter of 19 mm × 19 mm and a disc having a diameter of 100 mm × 17 mm. After that, CIP treatment was performed at 200 MPa using a cold hydrostatic isotropic press .The obtained zirconia block/disc was degreased at 500 °C in an inert gas oven  and then fired in a firing furnace  at 970 °C, to obtain a semi-sintered zirconia block/disk (φ18 mm × 18 mm/φ98.5 mm × 16 mm).The semi-sintered zirconia block/disk was cut with a cutting machine , and the surface was polished with SiC water-resistant polishing paper (# 1000), to reach a shape suitable for each test.Each test piece was subjected to high-speed sintering  or conventional sintering . CEREC Speed fire  was used for high-speed sintering, and AUSTROMAT 674i  was used for conventional sintering. Each sintering process was performed according to the schedule shown in Each sintered body was ground by a surface grinding machine  using diamond wheels  and processed to the dimensions corresponding to each test . SpecimeA: content of alumina (wt%);Ρ: measured density (g/cm3);ρ0: theoretical density (g/cm3);ρA: theoretical density of alumina;ρx: theoretical density of zirconia containing 5.5 mol% of yttria (6.0254 g/cm3 [54 g/cm3 ).The density of the specimens was measured by the Archimedes method (n = 3). The measurement was carried out in accordance with JIS R 1634: 1998. From the obtained density, the relative density was calculated by the following equation:Crystal structure characterization of the specimens was performed by X-ray Diffraction . The measurement was performed using CuKα as the X-ray source, tube current and tube voltage of 40 mA and 40 kV, respectively, 2θ range of 20–120°, scan step of 0.02°. A Rietveld analysis was performed for each diffraction profile using Rietan-FP . For thec/a was calculated from the lattice constant refined by Rietveld analysis. The yttria concentration in tetragonal zirconia was calculated using the following equations, as given by Miller et al. [The tetragonality r et al. :(2)YO1.5Microscopic characterization was performed by SEM  at an acceleration voltage of 15 kV. The specimens used for XRD were the same as those used for SEM observation. The specimens were Au-coated to prevent charge-up.TP (Translucency Parameter) according to the following equation:L*, a*, b*: CIE L* a* b* value;w: measured with the white background;Subscript b: measured with the black background.Subscript The translucency was evaluated by computing the L* a* b* of each specimen was measured by a spectroscopic colorimeter . The specimens were measured on a black and white background (n = 2).The σ (MPa) was calculated according to the following equation in accordance with ISO 6872:P: breaking load (N);L: test span (mm);w: width of the specimen (mm);b: thickness of the specimen (mm).The three-point flexural test was conducted in accordance with ISO6872  (n = 10). In order to investigate the effect of the specimen pre-sintered thickness on the strength, specimens made from two types of semi-sintered bodies with different thicknesses were tested . The tesK1C (F: fracture load (MN);S: test span (mm);w: specimen thickness (mm);b: specimen width (mm);α: relative V-notch depth (mm).a: average notch depth (mm);The fracture toughness test used the SEVNB method in accordance with ISO 6872 (n = 5). In this test, two types of specimens with different thicknesses (22 mm (l) × 4.0 mm (w) × 3.0 mm (b) and 22 mm (l) × 4.0 mm (w) × 1.5 mm (b)) were used in order to investigate the effect of the specimen pre-sintered thickness on the fracture toughness. The V-notch was applied along the thickness direction of each test piece to a depth of 0.8 to 1.2 mm, an angle of less than 20°, and a tip diameter of less than 20 μm using a razor blade . The test was carried out using a universal testing machine  under the conditions of a span of 16 mm and a crosshead speed of 0.5 mm/min. The fracture toughness value, ISO 6872 :(6)K1C=t-test was used to compare 5Y-SS and 5Y-CS in relative density and TP (specimen pre-sintered thickness 1.9 mm). Flexural strength and fracture toughness were analyzed using two-way analysis of variance (two-way ANOVA). The level of significance was set at 0.05 for all analyses.The Contrary to this study, Cokic et al.  reportedAs previously mentioned, Cokic et al. reported results that differed from those of the present study regarding the effect of high-speed sintering on the crystal phase composition of 5Y zirconia . In theiSince only a small amount of alumina was added to the zirconia raw material used in this study, precipitation of alumina particles was not observed in any specimen. The solubility of alumina in 8 mol% yttria-stabilized zirconia is reported to be ~1 wt% at 1500 °C . AlthougThe crystal phase composition is considered a factor affecting the translucency. Ceramic polycrystals generally exhibit higher translucency as they contain more optically isotropic crystal phases. From the XRD results, both 5Y-SS and 5Y-CS consist of tetragonal phases that are optically anisotropic. In the tetragonal phase, the lower the tetragonality, the closer to the optically isotropic cubic phase the sample becomes. Therefore, the light scattering due to optical anisotropy is reduced.Zhang et al. compared the translucency of a 5Y zirconia sintered body prepared by mixing 3Y zirconia powder and 8Y zirconia powder with the 5Y zirconia sintered body prepared from the uniform 5Y zirconia powder, and reported that the former was less translucent than the latter. Their study concluded that the higher the yttrium concentration of low yttrium tetragonal crystals, the higher the translucency when the overall yttrium concentration is the same .However, this study showed the opposite result to that reported by Zhang et al.: 5Y-SS had lower translucency than 5Y-CS, despite the high yttrium concentration of the low-yttrium tetragonal phase. This could be because, under the conditions of this experiment, the difference in the number of residual pores had a greater effect on translucency than the crystallographic difference.High translucency is the only reason to use 5Y zirconia, which is less strong than 3Y and 4Y zirconia, in dental prostheses. Therefore, it can be concluded that 5Y zirconia is not suitable for high-speed sintering applications.The results of the three-point flexural test and the fracture toughness test are shown in Crystal phase composition and microstructure are considered to be factors leading to low mechanical properties in 5Y-SS. Firstly, 5Y-SS has a lower content of low yttrium tetragonal and a higher yttria concentration in it than 5Y-CS. Therefore, the contribution of toughening caused by the “tetragonal → monoclinic stress-induced phase transformation” is smaller than that of 5Y-CS . As a reAs for flexural strength, the specimen thickness induced a significant difference: 5Y zirconia has a reduced flexural strength in thick specimens. This is because the residual pore concentration increases toward the center of the specimen. Moreover, since the fracture toughness does not change with specimen pre-sintered thickness, there is no difference in the degree of toughening caused by stress-induced phase transformation.5Y-SS-4.4 showed a flexural strength of 712 MPa. This strength value complies with ISO 6872 Class 4 . One Visit Treatment is not available for cases requiring prostheses larger than a 3-unit one, so 5Y-SS-4.4 seems to have a clinically suitable strength value. Even so, 5Y zirconia cannot be used for high-speed sintering because in some cases, e.g., pontic bridge, the dental prosthesis may be as thick as 10 mm. As mentioned above, the residual pores of 5Y-SS increase both in density and size as the specimen thickness increases . TherefoThis study shows that the translucency and mechanical properties of 5Y zirconia are greatly affected by high-speed sintering. On the other hand, previous studies on high-speed sintering did not show a significant reduction in translucency and mechanical properties of 3Y zirconia and 4Y zirconia ,14,29. TA similar discussion could be made for alumina. Matsui et al. reported that the addition of alumina to yttria-stabilized zirconia favors volume diffusion over grain boundary diffusion and increases the sintering rate . The addThis study revealed that high-speed sintering with Speedfire reduces the translucency and mechanical properties of 5Y zirconia. Crystallographic characterization by XRD and microstructure observation by SEM showed that these decreases were due to changes in crystal phase composition due to suppression of yttrium segregation and increased residual pores.Evaluation of pre-sintered specimens of various thickness revealed that the amount and size of residual pores inside 5Y zirconia increase as the specimen’s pre-sintered thickness increases, resulting in reduced translucency and mechanical properties. Especially as regards high-speed sintering, 5Y zirconia is not suitable for thicker dental prostheses because the translucency and strength are significantly reduced when the pre-sintered thickness is 8 mm or more.Discussions on the relationship between chemical composition and the effects of high-speed sintering suggested that high yttrium concentrations and the addition of alumina could adversely affect high-speed sintered zirconia.From the above results, we conclude that 5Y zirconia is not suitable for high-speed sintering applications.


Increasing the level of propylene oxide from 5% to 25% caused a significant increase in the substitution degree (DS) and swelling ability of starches and reduced the syneresis, while with increasing acid hydrolysis time from 5 h to 20 h, starch swelling decreased and syneresis increased (p < .05). AH process at high hydrolysis times (20 h) increased the gelatinization temperatures and decreased retrogradation temperatures. Increasing the level of propylene oxide in both single and dual modification reduced the temperatures and enthalpy of gelatinization and retrogradation of sago starch. In summary, dually modified sago starch has a great potential to use in specific food products such as frozen dough or frozen bakery products.The aim of this study was to evaluate the characteristics of dually modified sago starch by acid hydrolysis (AH)‐hydroxypropylation (HP). For this purpose, sago starch was modified with the combination by AH (5–20 h hydrolysis times) followed by HP (5%–25% ratio of propylene oxide) processes. The results showed that the dual modification of the sago starch structure didn't have a significant effect on the size of starch granules, and the granule size was in the range of 0.005–0.151 µm; however, the pasting properties and the glass transition temperature decreased significantly ( p < .05).Evaluation of the characteristics of dually modified sago starch by acid hydrolysis (AH)‐hydroxypropylation (HP). Increasing the level of propylene oxide from 5% to 25% caused a significant increase in the substitution degree (DS) and swelling ability of starches and reduced the syneresis, while with increasing acid hydrolysis time from 5 h to 20 h, starch swelling decreased and solubility in water increased ( For example, modifying the structure of native starches improves their behaviors in terms of retrogradation, pasting, and gelatinization , two similar methods are used, for example, two physical or two chemical methods. However, in the second type (heterogeneous), two different methods are used, such as combining the physical and chemical methods  was done by hydrochloric acid, and then hydroxypropylation (HP) of the hydrolyzed starch was performed. The sago starch slurry was prepared by mixing starch  with a dilute solution of hydrochloric acid (0.14 N) at 50°C to reach a final weight of 1000 g. While stirring (at 200 rpm), the starch slurry was incubated at 50°C for 5, 10, 15, and 20 h to prepare hydrolyzed sago starch with various molecular weights. After that, the pH of starch suspensions was reached 5.5 by the addition of 1% sodium hydroxide. The starch samples were then washed with distilled water and filtered through Whatman No. 4 filter paper. The hydrolyzed sago starches were kept at 40°C overnight in an oven to dry completely . For this purpose, 1 g of starch was coated with a layer of gold/palladium and transferred to the SEM and finally observed at 20 kV  and then heated at 60°C in a water bath to dissolve the starch sample. The starch solution was cooled at room temperature and diluted with distilled water (to a volume of 100 ml). The starch solution (1 ml) was transferred into graduated test tubes (25 ml) and immersed in an ice bath, and concentrated H2SO4 (8 ml) was incorporated dropwise. After complete stirring, the tubes were kept for 20 min in a hot water bath and then transferred to an ice bath. 0.6 ml of ninhydrin reagent solution (3% ninhydrin in 5% Na2S2O5) was incorporated into the solutions. After shaking, the tubes were placed in a hot water bath at 25°C for 100 min. The volume of solution was reached 25 ml with the addition of concentrated H2SO4 and stirred and kept still for 10 min. The absorbance of the starch solution was read at 590 nm. MS of the starch sample was obtained through the following equation: where W and M are the equivalent hydroxypropyl in 100 g of starch, and the molecular weight of C3H6O, respectively  and mixed with distilled water (30 ml). While stirring, the tube was heated in a hot water bath at 95°C for 30 min. The sample was then cooled with cold water to reach room temperature and then centrifuged for 15 min at 700 × g. The resulting supernatant was transferred to a container and dried (at 120°C for 4 h). Finally, the starch sample was weighed, and its water solubility and swelling amounts were obtained through the following equations . The starch sample (4 g) was mixed with distilled water (25 g). The initial desired speed and the speed of the resting stage were 960 rpm and 160 rpm, respectively. At first, the starch sample was kept at 50°C for 1 min, and then its temperature increased rapidly to 95°C (at a speed of 14°C/min) and kept at this temperature for about 5 min. After that, the sample was cooled to 50°C and kept for 2 min at this temperature. In this experiment, pasting temperature, time to reach peak viscosity, peak, and final viscosity were studied . The starch suspension in distilled water (in a ratio of 3:1 w/w) was prepared and weighed in the steel container of the DSC device and kept for 24 h at room temperature to reach equilibrium. The container containing the starch suspension was then transferred into the DSC device and heated and scanned at 10–115°C. A DSC container without starch suspension was used as a control. The thermal characteristics of starch samples including onset temperature (To), peak temperature (Tp), conclusion temperature (Tc), and gelatinization enthalpy (ΔH) were calculated from the DSC curves  for 3 weeks, and then their onset temperature (To), peak temperature (Tp), final temperature (Tf), and gelatinization enthalpy (ΔH) were measured by the DSC device  was prepared and heated for 30 min at 90°C. The starch suspension was cooled in an ice‐water bath to room temperature and then centrifuged at 3200 rpm for 15 min. Finally, the syneresis of starch gel was reported as a percentage of the amount of water separated after centrifugation  followed by Duncan multirange post hoc test was used to compare means at 33.1SEM micrographs of native sago starch and dual modified starches by acid hydrolysis‐hydroxypropylation. As can be seen in the figure, the dual modification of the sago starch structure caused partial destruction of the modified starch structure and increased the depressions in the surface of the granules, and also increased the accumulation of starch granules. Sago starch granules generally had an irregular round shape.Figure SEM micrographs of hydroxypropylated tapioca starch were approximately identical to those of native starch; however, the dual modification of this starch by carboxymethyl and hydroxypropyl caused the irregular shape of the granules. Surendra Babu et al. . Increasing the acid hydrolysis time at a constant level of 5% propylene oxide increased the MS values; however, at other levels of etherifying agent (propylene oxide), increasing the acid hydrolysis time didn't show a significant effect. The efficiency of hydroxypropylation depends on the diffusion or penetration of the etherifying agent and alkaline catalyst intro the granules of starch and the reactivity between the propylene oxide and starch alcoholate nucleophile  of hydroxypropyl groups in the structure of granular starches was used to determine the efficiency of the hydroxylpropylation and acid hydrolysis process , so that the water solubility value of native sago starch was 47.59%, and in HP5AH20, HP15AH10, HP15AH15, HP15AH20, HP25AH10, HP25AH15, and HP25AH20, the solubility reached 100%. Increasing water solubility of sago starch due to acid hydrolysis can be caused by breaking of amine and substructures into smaller structures as well as degradation of amylopectin structures and production of linear structures similar to amylose . At constant levels of propylene oxide, with increasing the acid hydrolysis time from 5 to 20 h, the swelling rate of starches decreased significantly (p < .05). Decreased swelling of starches due to the acid hydrolysis process may be due to an increase in the high proportion of soluble dextrin in the short and long chains in the starch granules . This increase is probably due to the fact that during the hydroxypropylation process, the starch structure weakens and the water penetration into the granules increases, as a result of which the water absorption capacity of the starch granules increases and their swelling power increases . At constant levels of propylene oxide, with increasing acid hydrolysis time from 5 to 20 h, the pasting properties of sago starch decreased, and also at constant times of acid hydrolysis, increasing the ratio of propylene oxide from 5% to 25% led to a significant reduction in pasting properties of modified starches (p < .05). The pasting temperature, the time to reach the peak viscosity, peak viscosity, and final viscosity of the sago starch samples, were in the range of 56.57–73.11°C, 1.86–4.83 min, 236.55–414.38 cP, and 283–323.40 cP, respectively. In general, the highest amount of pasting properties was observed in the native sago starch, and the lowest amount of these properties was related to HP25AH20. The results obtained from the study of pasting properties of modified sago starch generally demonstrated an increase in the strength of intermolecular bonding forces due to the chemical modification of the starch structure. The decrease in the peak and final viscosity of sago starch due to hydroxypropylation is due to the fact that hydrophilic groups weaken the network and cause excess water to enter the starch micelle and increase the solubility of starch  . At a constant ratio of propylene oxide, increasing the acid hydrolysis time from 5 to 20 h partially increased the gelatinization temperatures and decreased the enthalpy of modified starch samples, but these changes were not significant in most cases. The slight decrease in enthalpy of acid hydrolyzed starches is probably due to the fact that acid hydrolysis destroys some of the double helixes in both the crystalline and amorphous regions, thereby melting fewer double helixes during gelatinization and the enthalpy slightly reduced . During the hydroxypropylation process, the active groups introduced into the starch chains are able to destroy intramolecular and intermolecular bonds and increase water access and decrease gelatinization temperature. The decrease in gelatinization enthalpy due to hydroxypropylation is also related to the degradation of double helixes in amorphous regions by hydroxypropyl groups. As a result, the number of double helixes that dissolve and melt during gelatinization will be lower in hydroxypropylated starches. The values of the To, Tp, Tc, and ΔH of different sago starch samples were in the range of 63.40–70.82°C, 72.77–78.92°C, 75.27–82.11°C, and 10.44–13.38 J/g, respectively. Gelatinization enthalpy indicates the energy required to destroy the organized structure of starch. In fact, low enthalpy demonstrates less stability of starch crystals and the structural order . Increasing the propylene oxide ratio and acid hydrolysis time caused a significant decrease in Tg (p < .05). The lowest Tg was observed in HP25AH20 (57.01°C). In general, acid hydrolysis and hydroxypropylation reduced the order of sago starch structure and thus significantly reduced the Tg compared to native sago starch (p < .05). Decreased Tg of modified starches due to acid hydrolysis and hydroxypropylation process has been reported by other researchers  is the temperature at which the glass state becomes a rubbery state. The more crystalline and glassy the starch polymer and the more orderly it is, the higher the Tg . At constant acid hydrolysis time, by increasing the propylene oxide ratio from 5% to 25%, the temperatures and enthalpy of retrogradation significantly decreased (p < .05). At a constant ratio of propylene oxide, increasing the time of acid hydrolysis also caused a slight decrease in starch retrogradation temperatures, but these reductions weren't significant in most cases. The lowest temperatures and enthalpy of retrogradation were obtained in the HP25AH20. The To, Tp, Tc, and ΔH of retrogradation of sago starch samples were in the range of 44.16–54.18°C, 54.74–60.27°C, 58.99–65.25°C, and 1.05–5.16 J/g, respectively.Changes in starch during gelatinization and retrogradation are important to evaluate its functional properties for food processing, during digestion and in industrial applications . However, at a constant ratio of propylene oxide, increasing the acid hydrolysis time from 5 to 20 h led to a significant increase in the percentage of syneresis (p < .05). The highest and lowest syneresis values were observed in HP5AH20 (4.65%) and HP25AH5 (1.61%), respectively. The syneresis is due to rearrangement and subsequent crosslinking between the amylopectin and amylose, but because the hydroxypropyl groups attached to the amylopectin and amylose during the hydroxypropylation process create a spatial barrier, this barrier prevents the chains from coming too close to each other during storage and reduces syneresis (Kaur et al., The syneresis percentage of native and dual modified sago starches by acid hydrolysis‐hydroxypropylation is compared in Figure 4In this study, it is observed that the dual modification of sago starch structure by acid hydrolysis‐hydroxypropylation improves the starch water solubility. Dual modification of starches at low acid hydrolysis time and high ratio of propylene oxide led to a remarkable reduction in the retrogradation intensity and syneresis percentage of modified starches compared to native sago starch. Due to the dual modification, the structure of sago starch became more irregular, and the peak viscosity occurred in less time. The results of this study generally demonstrated that the dual modified sago starch, especially low acid hydrolysis time and high ratio of propylene oxide, can be used in the food industry to reduce the staling rate and syneresis of food products.We thank Prof. Fazilah Ariffin from Universiti Sains Malaysia for her valuable input and critical reading of this manuscript.The authors declare no conflict of interest.This study does not involve any human or animal testing.


Article title: Nano-drug co-delivery system of natural active ingredients and chemotherapy drugs for cancer treatment: a reviewAuthors: Bingqian Li, Huili Shao, Lei Gao, Huan Li, Huagang Sheng, and Liqiao ZhuJournal:Drug DeliveryBibliometrics: Volume 29, Number 1, pages 2130–2161DOI:https://doi.org/10.1080/10717544.2022.2094498As per author’s request, the captions of figure 6 and 8 should be revised as shown below.International Journal of Nanomedicine 2020; 15: 10285–10304’ Originally published by and used with permission from Dove Medical Press Ltd.Figure 6. Illustration of the preparation, dual-drugs loading, pH-responsive intracellular release of MSNCA@GODOX-HA nanoparticles and the apoptosis induction in MCF-7 cells. International Journal of Nanomedicine 2021; 16: 1775–1787’ Originally published by and used with permission from Dove Medical Press Ltd.Figure 8. Schematic representation of the carrier-free nanoparticles (NPs) via co-assembly between UA and MTX.


While several CeD-relevant gluten T cell epitopes have been identified, epitopes recognized by a substantial proportion of gluten-reactive T cells remain unknown. The identification of such CeD-driving gluten epitopes is important for the food industry and in clinical settings. Here, we have combined the knowledge of a distinct phenotype of gluten-reactive T cells and key features of known gluten epitopes for the discovery of unknown epitopes. We tested 42 wheat gluten–reactive T cell clones, isolated on the basis of their distinct phenotype and with no reactivity to known epitopes, against a panel of synthetic peptides bioinformatically identified from a wheat gluten protein database. We were able to assign reactivity to 10 T cell clones and identified a 9-nucleotide oligomer core region of five previously uncharacterized gliadin/glutenin epitopes. This work represents an advance in the effort to identify CeD-driving gluten epitopes.CD4 Knowledge-based strategy identified five previously uncharacterized wheat gluten T-cell epitopes implicated in celiac disease. Three main selection factors have been identified, including (i) proteolytic stability to gastrointestinal digestion, (ii) substrate affinity to the enzyme transglutaminase 2 (TG2) mediating deamidation, and (iii) selectivity in binding to disease-predisposing HLA molecules  that are hallmarks of the gluten-specific T cells  from patients with CeD, 30 to 50% were found to be unreactive to known epitopes (Triticum aestivum) (table S1).In this study, we selected 179 TCCs generated in a previous study . This search generated a finite list of 17 unique peptide sequences in no particular order, of which 5 were known gliadin/glutenin epitopes.We identified a motif, P-[FQ]-P-Q-[PLQ]-[PQ]-[FLQY]-P-[FQWY], predominantly present in the native peptide sequences of four immunodominant gliadin/glutenin epitopes—DQ2.5-glia-α1a (PFPQPQLPY), DQ2.5-glia-α2 (PQPQLPYPQ), DQ2.5-glia-ω1 (PFPQPQQPF), and DQ2.5-glia-ω2 (PQPQQPFPW)—and searched for this motif in the GluPro I database by using the software tool ScanProsite (n = 17) (table S2), namely, TG2 deamidation preferences, amino acid composition, and immunodominance. Specifically, we designed a mixture model composed of three hierarchical hidden Markov models, where each included a position weight matrix–like subpath, to predict and score candidate 9-nucleotide oligomer sequences. These position weight matrices were created on the basis of the following parameters: (i) the presence of deamidation patterns “QXP” and “QXX” (where X can be any amino acid) at positions 4, 6, or both of the 9-nucleotide oligomer amino acid sequence, where a separate position weight matrix of amino acid preference was estimated for each pattern based on the amino acid composition of deamidation patterns of known gliadin/glutenin epitopes, and (ii) amino acid preference in the 9-nucleotide oligomer core sequences of the known gliadin/glutenin epitopes outside the deamidation patterns, as well as an arbitrarily weighted preference of such amino acids present in the four immunodominant gliadin epitopes (table S2). In addition, the algorithm did not allow generation of 9-nucleotide oligomer sequences with more than four consecutive glutamine residues (QQQQ) and the presence of two consecutive prolines in the deamidation pattern (QPP).Next, we developed a more advanced algorithm based on characteristic features of all known HLA-DQ2.5–restricted gliadin/glutenin epitopes . In strategy 2B, scores corresponding to each 9-nucleotide oligomer were multiplied with the number of hits within the GluPro I database to generate the second list of top 100 peptide sequence of potential gliadin/glutenin epitopes (table S3). Last, we selected the top 10 scoring 9-nucleotide oligomer peptide sequences of potential gliadin/glutenin epitopes from each variant of strategy 2 (2A and 2B), where five sequences were overlapping .Together, from strategies 1 and 2, we selected 18 unique peptide sequences of potential gliadin/glutenin epitopes, of which 9 were identified by both strategies . These 1We tested the reactivity of 42 of 56 gliadin/glutenin-reactive TCCs with unknown epitope specificity (table S1) against a panel of 18 selected TG2-deamidated synthetic 13-nucleotide oligomer peptides representing the potential novel gliadin/glutenin epitopes  in T celTo identify the true 9-nucleotide oligomer core sequences of these candidate epitopes, we designed shorter peptides derived from the 13-nucleotide oligomer peptides representing all the possible 9-nucleotide oligomer HLA-DQ2.5 peptide–binding registers . All of Together, we were able to identify five previously unknown epitopes, of which two originated from α-gliadin, two from γ-gliadin, and one from ω-gliadin. On the basis of previously established nomenclature, the tentative names DQ2.5-glia-α4 (PQPEQPYPQ), DQ2.5-glia-α5 (PQPEYPQPQ), DQ2.5-glia-γ4f (PFPQPEQEL), DQ2.5-glia-γ6 (PFPQPEQEL), and DQ2.5-glia-ω3 (PFPEQPYPE) are suggested . When we+ T cells recognizing peptides from cereal gluten proteins of wheat, barley, and rye are the key players in the pathogenesis of CeD  in triplicate, and the results show one representative independent experiment.The main aim of this study was to develop an efficient method for identification of yet unidentified gluten epitopes. To do that, we obtained gluten-reactive TCCs with unknown epitope specificity. This was done by assessing the grain reactivity and epitope specificity of TCCs isolated on the basis of the phenotype typical for gluten-reactive T cells. To increase the chances of obtaining TCCs with unknown gluten epitope specificity, we only selected for TCCs that previously did not bind to HLA-DQ2.5 tetramers representing five immunodominant gluten epitopes. In addition, we designed an efficient strategy to identify candidate gluten epitopes. This was done by using the prior knowledge of the hitherto identified gluten epitopes to generate candidate peptide sequences and subsequently searching the GluProI The study was approved by the Regional Committee for Medical and Health Research Ethics South-East Norway (project no. 6544). All patient samples were collected with an informed written consent from patients who visited the endoscopy unit at Oslo University Hospital—Rikshospitalet or the endoscopy unit at Akershus University Hospital for the endoscopic routine procedure for the diagnosis of CeD.+, CD4+, PD-1+, CD39+, CD161+, ICOS+, CXCR3+, CD25−, and CD127-) (+) or not (Ttet-). The antigen-free culture medium was composed of feeder mix {irradiated [60 gray (Gy)] peripheral mononuclear cells from three healthy donors, 1 × 106/ml} in 10% human serum (HS) , RPMI 1640 (Sigma-Aldrich), supplemented with penicillin-streptomycin (Sigma-Aldrich), 0.01 M β-mercapthoethanol (Sigma-Aldrich), interleukin-2 , IL-15 , and phytohemagglutinin (PHA) . TCCs were generated by performing cloning by limiting dilution (one TCC per three wells in a volume of 20 μl) using Terasaki plates (VWR). TCCs were cultured for 10 days in Terasaki plates that were placed in a moist chamber inside a humidified incubator at 37°C with 5% CO2. All growing TCCs were expanded for an additional 10 days into a well of a 48-well culture plate (Corning) with antigen-free culture medium described above. The TCCs were supplemented with additional medium , supplemented with penicillin-streptomycin (Sigma-Aldrich), 0.01 M β-mercapthoethanol (Sigma-Aldrich), IL-2 , and IL-15  as required during the 10 days. The TCCs were either used directly from culture or cryopreserved before being used in T cell proliferation assays.The TCCs used in the current study were generated from biopsy samples from five untreated patients with CeD  recruited for a different study  at 1:100 w/w at 37°C for 5 hours and later dialyzed twice against NH4HCO3 , at first for 5 hours at 4°C and later overnight also at 4°C. Dialyzed proteins were stored as freeze-dried pellets at −20°C. The proteins were then resuspended in 100 mM (pH 7.4) tris-HCl containing 2 mM CaCl2 for a protein concentration of 1 mg/ml and deamidated using in-house–produced recombinant human TG2 (50 μg/ml) for 2 hours at 37°C. The deamidated proteins were used in T cell proliferation assays.Wheat (gliadin/gluteninin), barley (hordein), and rye  proteins were extracted in-house from grocery store flours, wheat (Møllerens—siktet hvetemel), barley , and rye (Møllerens—siktet rugmel), as described previously (2 for a protein concentration of 500 μM in a volume of 500 μl and deamidated using in-house–produced TG2 (100 μg/ml) for 2 hours at 37°C.All the peptides used in this study were commercially synthesized by GenScript at a minimal purity of 90% and with quality assessment by reversed-phase high-performance liquid chromatography and electrospray ionization mass spectrometry. No additional modifications were introduced into synthesized peptides with the exception of peptides with N-terminal glutamine (Q) that were N-terminally acetylated to prevent pyroglutamate formation. Peptides in 3H-thymidine  diluted in 0.9% NaCl solution (Braun) was added to the wells. The 3H-thymidine incorporation was measured no later than 16 hours after 3H-thymidine addition to the plates. Cells were harvested using an automated harvester , and the thymidine incorporation was measured by liquid stimulation counting  as counts per minute (CPM). The stimulation of the TCCs by the tested antigen was assessed using the stimulation index (SI) calculated using the following formulaT cell proliferation assay was performed as described earlier , as described in Results, was implemented in Python (version 3.8). The code reads in a training set of known gluten epitopes, estimates a mixture model of sequence preference according to alternative deamidation patterns, and outputs predicted gluten epitopes according to this model. The output is given in deamidated and nondeamidated versions and with or without filtering and sorting of candidate epitopes according to their presence in provided fasta files (GluProI database) of gluten proteins.Statistical analysis was performed using GraphPad Prism software (version 8) (San Diego). Flow cytometry data were analyzed using FlowJo software (Three Star). All the figures were generated in Adobe Illustrator.


Starch hydrolysis by gut microbiota involves a diverse range of different enzymatic activities. Glucan-branching enzyme GlgB was identified as the most abundant glycosidase in Firmicutes in the swine intestine. GlgB converts α-(1→4)-linked amylose to form α- branching points. This study aimed to characterize GlgB cloned from a swine intestinal metagenome and to investigate its potential role in formation of α--branched α-glucans from starch. The branching activity of purified GlgB was determined with six different starches and pure amylose by quantification of amylose after treatment. GlgB reduced the amylose content of all 6 starches and amylose by more than 85% and displayed a higher preference towards amylose. The observed activity on raw starch indicated a potential role in the primary starch degradation in the large intestine as an enzyme that solubilizes amylose. The oligosaccharide profile showed an increased concentration of oligosaccharide introduced by GlgB that is not hydrolyzed by intestinal enzymes. This corresponded to a reduced in vitro starch digestibility when compared to untreated starch. The study improves our understanding of colonic starch fermentation and may allow starch conversion to produce food products with reduced digestibility and improved quality. Bacteroides thetaiotaomicron [Ruminococcus bromii, which releases oligosaccharides during the hydrolysis of resistant starch, facilitates the growth of other amylolytic bacteria and is, therefore, considered to be a keystone species for the metabolism of resistant starch [Dietary polysaccharides are a major source of energy for intestinal microorganisms in the gut of monogastric animals . Of the aomicron . In geneaomicron . A portiaomicron ,10,11,12t starch .Starch hydrolysis by intestinal bacteria is carried out predominantly by extracellular or periplasmic glycosyl hydrolase (GH) family 13 amylases or (neo-)pullulanases, which collectively hydrolyze α-(1→4)-, α-(1→6)- or α--linked α-glucans, including amylose and amylopectin . BranchiglgB coding for a glucan-branching enzyme found in swine intestine and to investigate its role in the formation of α--branched oligosaccharides from starch. In this study, glgB was cloned and over-expressed in E. coli to investigate the branching activity of the purified glucan-branching enzyme GlgB on amylose and starch and to elucidate its role in colonic starch utilization.To date, only a few branching enzymes from intestinal bacteria have been biochemically characterized ,19. It wglgB in swine intestinal microbiota was predicted based on the annotation of metagenomic-assembled genomes. The glgB sequence was cloned from an uncharacterized member of the phylum Firmicutes [glgB sequences were verified by PCR amplification of 1941 bp amplicons and sequencing . Purification of GlgB with a predicted molecular weight of 72 kDA was verified by SDS-PAGE -chains, but not the α- branching points. The resulting oligosaccharide profiles after hydrolysis were analyzed using HPAEC-PAD . StarcheThe size distribution of GlgB-treated starch was analyzed using HPSEC , with a To directly determine the branching activity of GlgB, reducing ends were quantified after the debranching of amylose and starches with isoamylase and pullulanase. The concentration of reducing ends was expressed in µM/g of starch . The conp < 0.05) reduced the glucose release for pea, fava bean and wheat starches. GlgB enzymatic treatment, thus, showed a moderate impact on the in vitro starch digestibility.The digestibility of GlgB-treated starch products was determined by measuring the amount of glucose released after digestion of the starch products with pancreatic amylases and brush border enzymes. The concentration of glucose released in the GlgB-treated and untreated starch samples were compared . GlgB trFirmicutes, was identified as the most abundant glycosidase in swine intestine [glgB from community DNA isolated from swine feces and expressed the gene in E. coli to characterize the enzyme activity on amylose and starches of different botanical origin. The branching activity of GlgB on amylose and starch was assessed by quantifying the reducing ends and by oligosaccharides analysis after hydrolysis with amylases, as well as an in vitro digestibility test, which provide us insight into its potential role for starch utilization in swine large intestine and in the development of functional foods.Intestinal bacterial communities in swine and other monogastric animals harbor an extensive metabolic potential for starch utilization, but the amylolytic system has only been fully characterized in a few species . The gluntestine . In thisglgB gene was isolated from Butyrivibrio fibrisolvens [Butyrivibrio fibrisolvens. The two enzymes share similar optimum conditions for enzymatic reaction, and both showed activity on amylose [Bifidobacterium longum [Rhodothermus obamensis, which preferred branched amylopectin as its acceptor substrate [Glucan-branching enzymes were predominantly studied from thermophilic microorganisms or hyper-thermophilic microorganisms; a commercially available branching enzyme is also derived from a hyper-thermophilic bacterium ,26,27,28isolvens . The ami amylose . Li et am longum . Howeverm longum . When coubstrate ,30. In aRuminococcaceae based on its 16S rRNA sequence [B. fibrisolvens in E. coli revealed extracellular starch-clearing activity [https://biocomputo.ibt.unam.mx/operon_mapper/, accessed on 27 January 2023) revealed that GlgB homologues are found in 6 different types of operons  linkages; however, brush border glycosyl hydrolases act slower on α-(1→6) linkages, when compared to α-(1→4) linkages, and slower on α- branching points than on α-(1→6)- or α-(1→4)-linked linear oligosaccharides ,17,25. HIn the baking industry, the nutritional and physical properties of bread are largely related to the physicochemical properties of starch . High amIn conclusion, the successfully cloned glucan-branching enzyme GlgB from swine intestinal bacteria showed strong branching activity, which forms branched oligosaccharides that are not hydrolyzed by intestinal enzymes. The biochemical characteristics of this branching enzyme indicate a higher preference towards amylose as its substrate, which further indicates a potential role in colonic starch digestion as an amylose solubilization enzyme. Those findings improved our understanding of colonic starch fermentation and may also allow starch conversion to produce bread with reduced digestibility while remaining higher quality.Starches were chosen to represent a diverse botanical origin and a range of amylose contents of 30–70%. Amylose from potato and starches from potato and wheat were purchased from Sigma Aldrich . Starches from pea, fava bean and barley with over 95% purity were kindly provided by Thava Vasanthan; these starches were obtained by aqueous extraction from seeds obtained from Tomtene Seed Farms, Birch Hills, Saskatchewan, Canada. The commercial amylases Termamyl (α-amylase) and Fungamyl  were provided by BioNeutra Inc. . Isoamylase HP  and pullulanase M1  were purchased from Megazyme .Escherichia coli BL21 Star (DE3)  with pET-28b+  was cultivated aerobically at 37 °C in Luria-Bertani (LB) broth containing 0.05 g/L kanamycin.Butyrivibrio fibrisolvens [glgB genes were amplified from intestinal community DNA [TM Taq DNA Polymerase High Fidelity, Invitrogen), with primers (5′ to 3′) B34F-SacI (GCTGAGCTCATGACAACTGTAGAAAAGAAA) and B34R-SalI (GAAGTCGACGAATTCAAATACCGCAACG), using DNA isolated from fecal samples [glgB. Chemically competent cells of E. coli BL21 Star (DE3)  were transformed with the recombinant plasmids, according to the One Shot BL21 (DE3) Competent Cell Manual . Transformants were screened with the primers B34F-SacI and B34R-SalI to identify clones harboring glgB, and the sequence of the insert was verified by Sanger-sequencing using the T7 primers 5′-TAATACGACTCACTATAGGG-3′ . Clones B342 and B344 share the same nucleotide sequence , and clone B342 was selected for all subsequent experiments.Homologues of starch branching enzymes were identified in metagenomic assembled genomes by protein blast . Two proisolvens  were selnity DNA  with hig samples  as templE. coli was induced by addition of 0.2 mM isopropyl β-D-1-thiogalactopyranoside (IPTG) to exponentially growing cultures in LB broth, corresponding to an optical density (OD600nm) of about 0.4, followed by overnight incubation at 25 °C. Cells were harvested by centrifugation at 5000 rpm for 10 min and disrupted with a bead beater for 20 s for 8 times. GlgB was purified using the HisPurTM Ni-NTA Resin , concentrated using an Amicon® centrifugal filter with 30 kDa molecular weight cut off . Purification was verified by sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Protein concentration was measured by Bio-Rad protein assay dye reagent , with bovine serum albumin as the standard.Overexpression of GlgB in Amylose from potato and starch from pea, fava bean, potato, corn, wheat and barley were used as substrates. The enzyme activity of GlgB was determined by measuring the reduction of the iodine-binding amylose , with mov/v) α-amylase at 95 °C and pH 5–6 for 1.5 h, followed by incubation with 0.02% β-amylase at 55 °C for 24 h. The oligosaccharides profiles after amylase hydrolysis were analyzed using high-performance anion-exchange chromatography, coupled to pulsed amperometric detection (HPAEC-PAD) on a Dionex ICS-3000 Ion Chromatography System . The samples were separated on a Carbopac PA20, coupled to an ED40 chemical detector . Water (A), 0.2 M NaOH (B) and 1 M NaOAc (C) were used as eluents, and samples were eluted at a 0.25 mL/min flow rate with the following gradients: 0 min, 68.3% A, 30.4% B and 1.3% C; 30 min, 54.6% A, 30.4% B and 15.0% C; 50 min, 46.6% A, 30.4% B and 23% C; 95 min, 33.3% A, 30.4% B and 36.3% C; followed by re-equilibration. Glucose, fructose, isomaltose and maltose were used as standards. Untreated amylose and starches served as controls.To determine the presence of branching points that are resistant to hydrolysis of linear α-(1→4)-chains by amylase, GlgB-treated amylose and starches were incubated with 0.02% (The molecular size distribution of starch samples after GlgB treatment was determined using high-performance size-exclusion chromatography (HPSEC) on an Agilent 1200 HPLC system , coupled to a refractive index (RI) detector. Starches were separated on a Superdex 200 Increase 10/300 GL column  that was eluted with 18 MΩ water at 0.2 mL/min. Untreated starches served as controls.The branching activity of GlgB was also determined by quantification of the branching points in GlgB-treated and untreated starches. Branching points were quantified by quantification of reducing ends after the debranching of amylose and starches with isoamylase and pullulanase. In brief, after GlgB treatment, the pH of amylose and starch solutions was adjusted to 4.5 using 1 M hydrochloride acid, and samples were incubated with 23 mg/L isoamylase and 241 mg/L pullulanase at 40 °C for 24 h. Reducing ends after debranching were quantified by quantification of reducing ends with bicinchoninic acid [g, and the glucose concentration was quantified using the glucose oxidase kit .The in vitro digestibility of starch samples with and without the GlgB treatment was quantified using pancreatic and intestinal brush border enzymes . Starch t-test. p < 0.05 was considered statistically significant. Results are expressed as averages ± standard deviation or as representative chromatograms.Data analysis of the reducing ends and in vitro digestibility assay was performed using paired


Small- and medium-sized enterprises (SMEs) play an important role in sustainable development not only for their significant contribution to China's economy but also for their large share of total discharged pollutants. Despite the widely acknowledged importance and benefits of environmental management accounting (EMA), the level of adoption and implementation of EMA practice is still weak within SMEs in many countries, especially in China. The current systematic review aims to identify the barriers affecting the Chinese SMEs for adopting EMA practices along with the critical success factors required for adopting EMA practices by SMEs and their top management for ensuring sustainable corporate environmental performance in China. The study is carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. In total, 73 articles were found to be eligible to be included in the systematic review, which was published on EMA in small- and medium-sized enterprises in China. Our study aims to document barriers to the adoption of EMA among Chinese SMEs. The review concluded that strict legislation and the availability of flexible financing options for SMEs can promote the adoption of EMA by SMEs. The establishment of environmental reporting systems and auditing mechanisms can further increase the utilization of EMA by small and medium firms. Barriers to EMA adoption can be mitigated after careful consideration of the current situation in SMEs. Documentation of significant barriers may help to form supportive policies which ultimately add to the efforts toward climate change mitigation. During the past two decades, a rapid evolution has been observed in the industrial and corporate sectors among the developed and developing economies. Along with the introduction of services and products to ensure improved standards of living, this evolution has brought upon a negative impact on the environment as well. Increased emission of gas from greenhouses, enhanced utilization of natural resources, and augmented waste and toxins disposal have a major consequence on climate change and organizational sustainability . To imprThroughout the globe among developed and developing countries, it has been observed that the regulatory policies promoting environmentally sustainable economic activity have usually focused on larger firms in the manufacturing sector. But in the current decade, the attention has been increased to the importance of small- and medium-sized enterprises (SMEs) in promoting environment-friendly businesses. Awareness regarding environmental issues and the relevant solutions has been increased among the current corporate stakeholders, which leads to their increased focus on the assessment of environmental performance , 9. The Larger firms are considered to be responsible for being the driving forces behind climate change and the depletion of natural resources. However, the newer small and medium enterprises contribute to approximately more than half of the material and energy resources utilization producing 64% of pollution in European countries . It is nSmall- and medium-sized enterprises (SMEs) play an important role in sustainable development not only for their significant contribution to China's economy but also for their large share of total discharged pollutants. China's economic and enterprise reforms since the year 1978 have dramatically altered the structure and dynamics of its enterprises. One of the most remarkable changes during the entire reform process is the rapid growth of SMEs . Each yeDespite the widely acknowledged importance and benefits of EMA, the level of adoption and implementation of EMA practice is still weak within SMEs in many countries, especially in China. This might be due to the low environmental awareness, ineffective role of professional bodies, lack of stakeholder pressure, weakness of environmental legislation, and firm difficulties . HoweverChina is a country where a high emphasis is laid on centralization by means of determining future moves through the use of its political ideology. Xu et al.  by usingTo weave a web of relationship between these thoughts, the systematic review seems sane approach which will enable to answer following research questions logically:Despite a long history of the presence of an accounting system in China, what are the barriers that hinder the way of SMEs adopting EMA practices?How perfect fit can be developed between Chinese political ideology and EMAP (Western)?How do Chinese SMEs follow the footstep of state-owned enterprises in the adoption of EMA for achieving sustainable corporate environmental performance?The current systematic review was carried out following the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) , 23 guidTo look for relevant articles, an initial search was carried out by using the keyword “Environmental Management Accounting Practices” in WOS, Scopus, and Google Scholar. The search came with 2,323 articles in WOS, 1,149 in Scopus, 980 in Google Scholar. The first refinement used “business, management, business finance, accounting” criteria that reduced the numbers to 126 in WOS, 289 in Scopus, and 74 in Google Scholar. The final refinement in which assessment was made by using PICO and CASP criteria's these numbers are further refined to 3 from WOS, 9 from Scopus, and 38 from Google Scholar. This means in total 50 articles were identified for EMAP. Similarly, the use of the keyword “Chinese SMEs” ended with 21 final papers for review. Similarly keyword “Sustainable Corporate Environmental Performance” came with 18 final articles. In the same vein keyword, political ideology came up with 23 articles from Google Scholar only. Apart from this, several other combinations were used which include “EMAP and Chinese Small and Medium Enterprise”: “EMAP and SME,” “EMA and SME,” “SMAP and SCEP,” and “Chinese SMEs and Sustainable Corporate Environmental Performance” came with results from 0 to max 20. The result of these articles was either totally irrelevant or they are already found in the initial research.The systematic search conducted through the use of mentioned databases generated a total of 9,546 papers published on the predefined keywords. The papers were screened for probable inclusion according to the PRISMA guidelines 1,592 were screened based on their titles and abstracts. Out of these, 792 articles were excluded after screening and the remaining 112 were assessed for eligibility to be included in a systematic review. These research articles were fully evaluated according to the research questions of the systematic review. Seventy-three articles were found to be eligible to be included in the systematic review. The subject-wise and database-wise details of 73 articles are in shown in The in-depth systematic review of 112 articles, assessed for their eligibility and enabled to highlighting of several themes which were identified in an attempt to search for arguments and findings from these studies to answer research questions. These themes were used as a guidance mechanism to arrange the 73 finalized articles for systematic review .Issues regarding business sustainability are becoming issues of prime importance for political and corporate stakeholders over the past decade . EMA serThe study by Bartolomeo et al.  providedInspired by the growing interest of researchers  further Dellios  while exThe economy of China is of global importance as every country has trade relations with it. China is considered as one of the lowest energy efficient economies of the world due to reduced environmental performance and inadequate natural resources. Despite this fact, firms in China have not focused on the environmental costs which have led to increased damage of ecosystems . RecentlZhou's  study exThe systematic review has revealed that the increased worldwide regulatory pressure for implementing EMA practices and reporting compliance to environmental certification organizations have led to adopting EMA practices in Chinese firms. It has been reported that managers working in heavy manufacturing companies are willing to change and adopt EMA due to regulatory, economic, environmental, and international pressure . In the Certain barriers have been identified toward the implementation of EMA practices which include lack of awareness, inadequate resources, and reduced external stakeholders support for the firms . Many SMThe government along with Chinese SMEs are engaged in pacing themselves with the international trend of protection of the environment. The main barriers of EMA are related to the specification of environmental accounting information, environmental costs allocation, issues related to legislation, and the lack of standardized environmental accounting standards. There is a need for market-sensitive instruments which are designed according to the Chinese economy . AnotherThis systematic review gave insights into the different factors that hinder the development and adoption of EMA practices in Chinese SMEs. The review concluded that strict legislation and the availability of flexible financing options for SMEs can promote the adoption of EMA by SMEs. The establishment of environmental reporting systems and auditing mechanisms can further increase the utilization of EMA by small and medium firms. The findings are useful for key governmental stakeholders to improve EMA practices implementation in Chinese firms. The current review contributes to the existing knowledge of EMA as this is a new area for Chinese SMEs. This systematic review focused on the following three questions.Despite the long history of the presence of an accounting system in China what are the barriers that hinder the way of SMEs adopt EMA?How perfect fit can be developed between the Chinese political ideology approach and western EMA?How do Chinese SMEs follow the footstep of state-owned enterprises in the adoption of EMA for achieving sustainable corporate performance?The analysis of the literature on EMAP can answer Q1, for instance, an important observation was made in the literature relating to the adoption of environmental management practices in the large companies and avoidance  by SMEs toward it; despite being responsible for causing environmental challenges . One reaIn the same vein, the analyses of literature on political ideology and western environmental management practices help answer Q2. The literature revealed that there was a time when both systems coexisted in China. Although after independence the traditional Confucius culture was ignored and more state roles emerged. This situation of the dominant role of the state is against very sole of western approach. The equilibrium between political ideologies of less state control to significant state control was achieved by the Chinese political leadership vision of the Ecological civilization approach. This approach enabled them to incorporate the positive aspect of western EMA in the Chinese accounting system , as globally it is regarded as a weapon of control, without comprising on their culture and political ideology. Achievement of this can be the perfect fit China needs to maintain its leadership position in creating a culture of an environmentally responsible nation.Lastly, Q3 the literature analysis suggests that SMEs who are challenged by limitation of resources can approach partner firms, education institutes, and industry councils for guidance on the implementation of EMAP for sustainable corporate performance.The raw data supporting the conclusions of this article will be made available by the authors, without undue reservation.FJ and FS: introduction. FJ: literature. FJ and ZF: formal analysis. FJ and KY: funding acquisition. KY: project supervision and proof reading. NI, ZF, and FS: review. NI and ZF: conclusion. NI: discussion. All authors contributed to the article and approved the submitted version.The authors declare that the research was conducted in the absence of any commercial or financial relationships that could be construed as a potential conflict of interest.All claims expressed in this article are solely those of the authors and do not necessarily represent those of their affiliated organizations, or those of the publisher, the editors and the reviewers. Any product that may be evaluated in this article, or claim that may be made by its manufacturer, is not guaranteed or endorsed by the publisher.


To evaluate the diagnostic performance of multiparametric transrectal ultrasound (TRUS) and to design diagnostic scoring systems based on four modes of TRUS to predict peripheral zone prostate cancer (PCa) and clinically significant prostate cancer (csPCa).A development cohort involved 124 nodules from 116 patients, and a validation cohort involved 72 nodules from 67 patients. Predictors for PCa and csPCa were extracted to construct PCa and csPCa models based on regression analysis of the development cohort. An external validation was performed to assess the performance of models using area under the curve (AUC). Then, PCa and csPCa diagnostic scoring systems were established to predict PCa and csPCa. The diagnostic accuracy was compared between PCa and csPCa scores and PI-RADS V2, using receiver operating characteristics (ROC) and decision curve analysis (DCA).Regression models were established as follows: PCa = − 8.284 + 4.674 × Margin + 1.707 × Adler grade + 3.072 × Enhancement patterns + 2.544 × SR; csPCa = − 7.201 + 2.680 × Margin + 2.583 × Enhancement patterns + 2.194 × SR. The PCa score ranged from 0 to 6 points, and the csPCa score ranged from 0 to 3 points. A PCa score of 5 or higher and a csPCa score of 3 had the greatest diagnostic performance. In the validation cohort, the AUC for the PCa score and PI-RADS V2 in diagnosing PCa were 0.879  and 0.873 (95%CI 0.778–0.969). For the diagnosis of csPCa, the AUC for the csPCa score and PI-RADS V2 were 0.806 (95%CI 0.700–0.912) and 0.829 (95%CI 0.727–0.931).The multiparametric TRUS diagnostic scoring systems permitted better identifications of peripheral zone PCa and csPCa, and their performances were comparable to that of PI-RADS V2.The online version contains supplementary material available at 10.1186/s12894-022-01013-8. Prostate cancer (PCa) is the most frequently diagnosed cancer among men in most countries of the world . In partMultiparametric magnetic resonance imaging (mpMRI) has proven to be particularly valuable for the evaluation of PCa, including detection, staging, and evaluation of aggressiveness . mpMRI iAdvanced prostate US imaging techniques have undergone incremental improvements in detection of PCa and csPCa, but none currently provides sufficient accuracy when considered separately. Some reports have suggested that multiparametric TRUS may offer an effective alternative for early diagnosis of PCa and csPCa , 11. To From January 2016 to March 2021, 116 patients with suspected PCa who were treated at the Second Affiliated Hospital of Soochow University were enrolled as a development cohort in this study. Then, we continuously enrolled 67 patients from the same center as a validation cohort. The inclusion criteria were: (1) patients who received standardized prostate multiparametric TRUS and mpMRI before biopsy; (2) an interval between prostate biopsy and imaging examinations of less than 1 week; (3) performing of standardized prostatic biopsy after examination and the availability of pathological results; (4) availability of PI-RADS V2 results; (5) location of the nodule in the peripheral zone; and (6) lack of radiation therapy, hormonal therapy or other treatments prior to examination. The exclusion criterion were: (1) unsatisfactory quality of images; (2) unable to give informed consent.Multiparametric TRUS was performed for patients presenting with an elevated prostate-specific antigen (PSA) level (> 4 ng/mL). Grayscale US, CDUS, CEUS and SE were performed with a US system (MyLab Twice) using an EC123 transrectal end-fire probe (3–9 MHz)  was administered intravenously. This was followed by administration of 5 mL of a normal saline flush. A video file was recorded to monitor perfusion behavior in the target lesion with time. We examined perfusion patterns of the target lesion compared to those of adjacent tissue. Fig. d. TargetAll cases were scanned thoroughly by two radiologists with 10 years of experience in TRUS. A total of 8 TRUS parameters for each lesion was obtained. Values of continuous variables (such as nodule size and SR) were recorded as numbers, and positive or negative results of binary variables  were recorded as 1 or 0.b values of 0 and 1000 s/mm2) and dynamic contrast-enhanced (DCE) images. Apparent diffusion coefficient maps were calculated on a designated workstation  with a 32-channel body phased array coil as the receiving coil. Scan sequences included sagittal T2-weighted images (T2WI), axial T2WI, T1WI, diffusion-weighted images (DWI)  were selected for the drawing of ROC curves. Parameters with AUC values greater than 0.5 were included in a binary logistic regression approach to establish two models: a PCa model and a csPCa model. Only TRUS parameters were included in the models, and the enter method was used while running the multivariable logistic regression. For each subpopulation, we performed a second logistic regression analysis using the dichotomized explanatory parameters, and then the coefficient of each of these parameters was divided by the smallest coefficient in the model and allocated a weight based on rounding this to the nearest integer. Specifically, the weight for each parameter was defined as the absolute value of the coefficient, and the overall score for each lesion was obtained by summing the weights. The point with highest sum of sensitivity and specificity was used as the diagnostic endpoint.Eight TRUS parameters in the PCa and non-PCa groups were compared, and the parameters that were significantly different between the two groups . Baseline patient data, including age, prostate volume, PSA and prostate-specific antigen density (PSAD) are presented as mean ± standard deviation. Binary parameters were evaluated through The characteristics of the development and validation cohorts are listed in Table For the Grayscale US , Grayscale US , CDUS  and SE  analyses, the interrater reliabilities were substantial. For the CEUS , the interrater reliability was almost perfect. For the PI-RADS V2, the interrater reliability was substantial . Taken together, these results demonstrate the consistently high agreement among raters and thus support the quality of the present analysis.P < 0.05). ROC curves of the 6 significantly different parameters were drawn, and these curves were also found to have AUC values larger than 0.5 (Table P > 0.05), which indicates that they are not of diagnostic value for PCa.Regarding the investigation of PCa by multiparametric TRUS, 8 TRUS parameters were extracted for analysis Table . Six of .5 Table . The othP < 0.05). ROC curves of the 7 significantly different parameters were drawn and were found to have AUC values larger than 0.5 (Table P > 0.05), which suggests that it does not have diagnostic value for csPCa.To explore to the diagnostic use of multiparametric TRUS in csPCa, 8 TRUS parameters were extracted for analysis Table . Seven o.5 Table . EchogenP = 0.46 and P = 0.37, respectively).The regression model of PCa and csPCa was developed based on the 6 and 7 significantly different parameters. The parameters ultimately the finally selected parameters were margin, Alder grade, enhancement patterns and SR for the PCa model, and margin, enhancement patterns and SR for the csPCa model. The resulting models were as follows: PCa = − 8.284 + 4.674 × Margin + 1.707 × Adler grade + 3.072 × Enhancement patterns + 2.544 × SR; csPCa = − 7.201 + 2.680 × Margin + 2.583 × Enhancement patterns + 2.194 × SR. No collinearity among parameters was noted; all tolerances were more than 0.1 and all variance inflation factors were less than 10. The PCa model was found to have an AUC of 0.971 . The csPCa model was found to have an AUC of 0.921 . Clearly greater AUCs were obtained for the PCa and csPCa models than for the use of any single parameter alone. The PCa and csPCa models both showed good calibration as assessed by the Hosmer–Lemeshow goodness-of-fit test . The AUC of the csPCa model was 0.880 .P < 0.001) and csPCa (P = 0.001). The diagnostic accuracy of different cutoff values of the PCa score and the csPCa score are shown in Table For the PCa score, we weighted the parameters by attributing 1 point to Adler grade and SR, and 2 points to margin and enhancement patterns, with a final score ranging from 0 to 6 points Table . For theP > 0.05)   and 0.873 (CI 0.778–0.969), respectively (05) Fig. a. For th05) Fig. b. As a rAccording to the DCA, in the development cohort, ranges of threshold probabilities from 15 to 100% for PCa and from 10 to 85% for csPCa were predictive of a net benefit of using PCa and csPCa scores for the diagnosis of PCa and csPCa. For PCa and csPCa, when threshold probabilities ranged from 42 to 100% and 30–85%, respectively, the related PCa and csPCa scores became more benefit as compared with PI-RADS V2  were obtained. Ultimately, a regression model based on 6 significant parameters in PCa and a regression model based on 7 significant parameters in csPCa were established in the development cohort. The diagnostic performance of both models was then validated using a validation cohort. In addition, we designed 2 simple multiparametric scores, including the PCa score and the csPCa score, to diagnose these two diseases.In patients with PCa, the parameters individually associated with the highest diagnostic accuracy were margin, Adler grade, enhancement patterns and SR. The good diagnostic accuracy of parameters involving CDUS, CEUS, and SR is not surprising. CDUS is well known to be able to reveal an increased number of visualized vessels as well as an increase in flow rate, size, and irregularity of vessels within a PCa lesion . CEUS alPCa tissue is stiffer than surrounding normal tissue due to several changes, including increased cellular density, destruction of glandular architecture, and development of stromal reactions combined with collagen deposition in the surrounding prostate parenchyma . Thus, SIn patients with csPCa, the parameters associated with the best diagnostic accuracy were margin, enhancement patterns and SR. Here, we focused more on the exclusion of CDUS from the csPCa model. CDUS reflects increased tumor blood vessels, but as lymph nodes increase as the tumor progresses, the ratio of the tumor volume to the total blood volume decreases, which may lead to less accurate CDUS scores.These analyses confirm that the various TRUS parameters are associated with a variable degree of diagnostic accuracy and that a combination of parameters has the potential to increase the diagnostic accuracy of PCa and csPCa. The research of Mingbo et al.  also demPCa score showed very good diagnostic accuracy in identifying patients with PCa, with an AUC of 0.920. Because confirming or excluding PCa has a significant impact on biopsy and treatment strategies, we propose the use of highly sensitive and highly specific cutoff scores (PCa score < 1 and ≥ 5) to exclude or confirm the diagnosis of PCa. csPCa score also showed very good diagnostic accuracy in identifying patients with csPCa, with an AUC of 0.806. We propose the use of a highly sensitive and highly specific cutoff score (csPCa score = 3) to confirm the diagnosis of csPCa. Mannaerts et al. believe that multiparametric US had significantly improved sensitivity for all csPCa definitions at the 2 Likert threshold, with a sensitivity of 74–85%, when considering a Likert score of 3 or greater to be suspicious . Our stuP > 0.05). These results are consistent with those of the study of Mingbo et al. [We futher investigated PCa and csPCa scores for identifying PCa and csPCa with an AUC of 0.879 and 0.806 in the validation cohort. Moreover, we analyzed the diagnostic performance of the PCa and csPCa scores as compared with PI-RADS V2. PCa score performance may be similar to that of PI-RADS V2 0.879 (95% CI 0.790–0.967) vs. 0.873 (95% CI 0.778–0.969) (o et al.  (mpUS: 0Based on results of DCA, patients with a 20–92% probability threshold in the PCa and a 22–83% probability threshold in the csPCa should be encouraged to undergo prostatic biopsy for further evaluation. Similarly, for patients with a 60–92% probability threshold in the PCa and a 59–83% probability threshold in the csPCa, clinicians should have more confidence in identifying PCa and csPCa using the multiparametic TRUS scoring system.Multiparametric TRUS currently lacks the standardization and consistency that PI-RADS V2 provides for mpMRI. As an initial exploration, our study established multiparametric TRUS diagnostic scoring systems, which may be seen as an important first step for multicenter standardization, evaluation and implementation of multiparametric TRUS in the clinical setting.However, our scoring systems still need to be improved. For example, limitations exists have been identified regarding systematic evaluations using that use real-time elastography identified to identify prostate cancer . In partIn addition, quantitative analysis of the CEUS was used in the CADMUS trial . This maThere were several limitations to this study. First, the current present study has used a relatively small sample size and is a retrospective, single-center study. Therefore, larger sample sizes with populations including diverse demographics from multiple institutions or race are necessary to validate our preliminary primary findings. Second, we did not include transition zone PCa and csPCa. Third, no pathological results of radical prostatectomy specimens were available for reference. Further research will continue to refine these diagnostic tools.We proposed regression models and diagnostic scoring systems based on multiparametric TRUS to assess peripheral zone PCa and csPCa and to improve the diagnostic performance of imaging techniques. The diagnostic power of these models is comparable to that of PI-RADS V2 analyses.Additional file 1. Lesions variables in the development cohort, shows all TRUS parameters and preoperative variables for each lesion in the development cohort.Additional file 2. Lesions variables in the validation cohort, shows all TRUS parameters and preoperative variables for each lesion in the validation cohort.


Correction to: Neurological Sciences (2022) 43:2571–2578https://doi.org/10.1007/s10072-021-05636-xMissing funding information has been added in the Funding Note.Funding Note Research partially funded by the Italian Ministry of Health to N.B.


Extrusion is a thermomechanical technology that has been widely used in the production of various starch-based foods and can transform raw materials into edible products with unique nutritional characteristics. Starch digestibility is a crucial nutritional factor that can largely determine the human postprandial glycemic response, and frequent consumption of foods with rapid starch digestibility is related to the occurrence of type 2 diabetes. The extrusion process involves starch degradation and order–disorder structural transition, which could result in large variance in starch digestibility in these foods depending on the raw material properties and processing conditions. It provides opportunities to modify starch digestibility by selecting a desirable combination of raw food materials and extrusion settings. This review firstly introduces the application of extrusion techniques in starch-based food production, while, more importantly, it discusses the effects of extrusion on the alteration of starch structures and consequentially starch digestibility in various foods. This review contains important information to generate a new generation of foods with slow starch digestibility by the extrusion technique. As the main source of carbohydrates and energy in the diet, starch has a critical role for human health. Starch in food can be divided into rapidly digestible starch (RDS), slowly digestible starch (SDS) and resistant starch (RS) according to its digestion rate and location in the human gastrointestinal tract . ConsumpExtrusion has been widely applied in the production of starch-based foods, such as biscuits, pasta and breakfast cereals, due to its convenience, high production efficiency and low cost . During This review aims to firstly introduce the extrusion technique and its application in the food industry, followed by a comprehensive review on the effects of extrusion on starch structures and digestibility, as well as corresponding mechanisms. Although some reviews have discussed the effect of extrusion on starch digestibility, this paper attempts to explain the digestibility of extruded starch from the perspective of different starch structure levels. This review could thus act as the basis for the development of extruded starch-based foods with slow starch digestibility  in the future.The aim of this section is to briefly introduce the extrusion technique, which could serve as the basis to better discuss and understand its effects on starch structures and digestibility in following sections. For further details on the extrusion technique, readers are encouraged to refer to other previous reviews .According to the number of screws, extruders can be divided into single-screw, twin-screw and multi-screw extruders  11]. Th. Th11]. The extrusion process can be generally described as follows: raw material enters the extruder from the feeding cavity and is transported forward in the barrel under the force of the rotating screw. Due to the friction among the screw, material and inner wall of the barrel, the material is strongly squeezed, stirred and sheared, resulting in further refinement and homogenization of the material. With the continuous increase in pressure and temperature in the barrel cavity, the raw material could be melted and changed from a solid state to fluid state when certain moisture content is present, accompanied by a series of physical and chemical reactions. When the material is finally discharged from the die of the extruder, the water from the extruded material evaporates quickly and produces a huge expansion force owing to the instantaneous pressure drop, which causes the extruded material to instantly expand, thereby forming a loose, porous and crispy expanded product ,13. ManyThere are many advantages of applying extrusion technology in food production. For example, the die of the extruder can be designed into a variety of complex structures c, thus gStarch has a complex structure, which can be generally divided into five levels . IndividEach level of starch structure can potentially have a significant effect on the final starch digestibility in different food products, depending on their order–disorder structural transition during food processing, as well as their physical, chemical or combined modifications. The major difference in starch digestibility in various foods is related to whether the starch is ingested native, gelatinized or retrograded. Native starch is inherently difficult to digest as it has crystalline  and short-range ordered structure (double helices)) and granule structures  . CrystalTherefore, it is conceivable that by modifying the order–disorder state of starch, including the long-range ordered structure  and short-range ordered structure (double helices), in various food products by extrusion could largely determine their starch digestibility. The following section is thus focused on the effects of extrusion on different levels of starch structures, aiming to elucidate the mechanisms by which extrusion affects starch structures and digestibility.Starch is a glucose polymer, which can be divided into amylose and amylopectin. Amylose typically accounts for 20–30% of starch and is an essentially linear molecule linked with α-1,4-glycosidic bonds. Amylopectin is a highly branched molecule connected by α-1,4 and α-1,6-glycosidic bonds. Starch molecules could undergo significant degradation during extrusion, which has a critical effect on the physiochemical properties and digestibility of starch . DiffereThe high temperature, pressure and mechanical shearing force in the extrusion process can easily break hydrogen bonds among starch molecules, especially with the amylopectin molecules . As showOn the other hand, SEC CLD results show that amylose also undergoes degradation during extrusion, causing the production of shorter amylose chains and the loss of iodine binding capacity by these amylose chains . InteresAs mentioned above, the degradation of starch molecules is of significance in terms of determining the starch digestibility in both its gelatinized and retrograded state. Excessive shearing may cause amylose to degrade into molecules with a much shorter chain, which cannot retrograde efficiently, inhibiting the formation of retrograded amylose double helices, which are known as type 3 RS (RS3) . Small dStarch granules are composed of semi-crystalline and amorphous growth rings (approximately 100~400 nm thickness), which can be frequently characterized by X-ray diffractometry (XRD) and small-angle X-ray scattering (SAXS) techniques . The semAs mechanically explained in the second section, extrusion involves both thermal and mechanical energy, which could largely damage the starch crystalline structure, including the long-range ordered structure  and short-range ordered structure (double helices). During extrusion, starch granules could rapidly absorb water and swell, leading to starch gelatinization. On the other hand, after extrusion, melted starch molecules could be re-associated into double helices during cooling, leading to starch retrogradation. Therefore, starch undergoes a transition between order and disorder structures (as mentioned above) over the extrusion process, involving both starch gelatinization and retrogradation; this process could significantly determine the starch digestibility in different starch-based foods .According to XRD results, the original diffraction peak intensity of native starch obviously decreases or disappears, and there may be new diffraction peaks appearing after extrusion  58]. Th. Th58]. As mentioned above, the digestion rate of native starch is largely determined by the starch crystalline structure. For example, hexagonal crystals are more difficult to be digested by starch digestive enzymes than orthorhombic crystals . AmyloseThere is large variance in starch granule structures among different starch sources due to the influence of genetics and the growing environment, which can be frequently characterized by scanning electron microscopy (SEM). For example, the size of starch granules varies from less than 1μm to more than 100 μm in diameter . Potato Extrusion could largely destroy the structural integrity of starch granules through fragmentation and finally results in irregular hole-shaped structures due to the sudden drop in pressure and evaporation of water when starch material is extruded from the die  30,75].,75.30,75Extrusion destroys the compact granular structure of starch and turns it into a loose and porous structure, which may promote the starch digestion rate and lead to less starch reaching the colon (a decrease in the RS content) . FurtherRaw material characteristics such as the source and size of starch granules, amylose/amylopectin ratio, lipid, protein and dietary fiber content could largely determine the digestibility of extruded starch. Bean genotype has been proven to affect the digestibility of starch, largely due to the varied organization and amylose content of starch granules . DependiAmylose content and structure  can affect the extruded starch digestibility by forming complexes with both endogenous and extrinsically added lipids, which is known as RS5 . This caProtein can form a matrix around starch granules, delaying or preventing its contact with digestive enzymes, thereby reducing starch digestibility . For exaFeed moisture has a significant effect on both starch structure and digestibility during extrusion . As the In terms of starch digestibility, the influence of moisture content depends on the balance between starch gelatinization and retrogradation  94]. St. St94]. Higher temperatures can frequently promote starch gelatinization and the destruction of starch crystallites during extrusion, which can thus increase the starch digestibility . For exaScrew speed is another critical factor affecting starch digestibility . With thp > 0.05) affect the starch digestibility of sorghum–barley blends [Besides moisture content, extrusion temperature and screw speed, other important extrusion variables, such as feed rate, screw configuration and die design, will also affect starch digestibility. The feed rate mainly affects the residence time of the material in the extruder barrel, which further affects the degree of starch gelatinization and degradation. For example, lower feed rates imply a longer residence time and enhanced shearing action on starch molecules. Therefore, feed rate had a negative effect on the RDS content of extruded bean powders . Howevery blends . The cony blends . Differey blends . The shaOverall, there are sometimes contradictory conclusions about the influence of different extrusion parameters on starch digestibility, which might be related to the botanical source of the starch. Depending on the plant source, the crystalline structure of starch and the ratio of amylose to amylopectin differ. In addition, flour is quite different from pure starch, because starch interacts with other ingredients in flour during extrusion. Therefore, from this point of view, it is impossible to draw a general conclusion about how extrusion parameters change the starch structure and digestibility, and this review can only provide partial references for explaining the mechanisms.Starch digestibility is a key factor in determining the human postprandial glycemic response, and the frequent consumption of RDS has been associated with the occurrence of many chronic diseases. Extrusion, as a common food processing technology, has a significant effect on the alteration of starch’s structure  and consequently starch digestibility. This review focused on the summarization of these effects and the possible mechanisms, with the aim to facilitate the development of starchy foods with slow starch digestibility. Extrusion could significantly degrade starch, especially amylopectin molecules around their branching points. Starch crystalline structures undergo continuous order–disorder–reorder transitions during extrusion, through starch gelatinization and retrogradation. As a result, the starch granule structure could also be largely modified. As a consequence, starch digestibility can be altered by extrusion processing. The alteration of starch digestibility by extrusion depends on the raw feed material composition, as well as the extrusion processing parameters, such as feed moisture, extrusion temperature and screw speed. This provides opportunities for developing starch-based foods with desirable starch digestibility by controlling these extrusion factors.However, many aspects remain to be investigated in the future, in order to better apply the extrusion technique to develop starch-based foods with slow starch digestibility. For example, it is known that many factors, including the raw feed material composition, extrusion moisture, temperature and screw speed, can affect the starch structure and digestibility. However, it remains unclear how these factors combined determine starch digestibility after extrusion. Most of the past studies only focus on a single or a few of these factors. Therefore, it is still highly necessary to systematically consider the effects of all these different factors on the starch digestibility after extrusion. Furthermore, extrusion is frequently used together with other techniques, such as acid or enzymatic treatments, in order to better modify starch properties. Investigations are required to fully understand the effects of the combination of these techniques with extrusion on starch digestibility in the future. The emergence of new food extrusion techniques such as supercritical fluid extrusion technology, two-stage or multi-stage extrusion and the combination of extruders and three-dimensional (3D) printers should also be investigated in the future in order to expand the applications of extrusion in modifying starch properties.