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We report on an extrusion test and its correlation with sensory perception. The extrusion test was implemented on a texture analyzer and applied to single-component or composite polysaccharide gels. The extrusion force did not depend strongly on the volumetric flow rate, indicating a predominantly elastic contribution to the force. The extrusion force correlated highly with sensory perception of the cutting effort and its ratio to the elastic modulus correlated highly with perception of the extensibility. A combination of the Young's modulus and the extrusion force correlated well with perception of firmness. The robust correlations depended weakly on the flow rate in extrusion, but were much higher for tapering ratios T ≥ 4.5 than for T = 2.5. Notably, the correlation obtained was higher than that with texture profile analysis parameters. We show the correlation of several empirical and fundamental large deformation tests with texture, and suggest that the higher correlation with extrusion reflects the closer mixed-mode deformation in mastication. Practical Applications The report highlights correlation of parameters from empirical and fundamental rheological tests with sensory evaluation. The forces generated in an empirical extrusion test emerge as appropriate and reliable descriptors of several sensory attributes. The approach outlined is appropriate in general for textural mapping of semisolid and solid foods with an apparent yield stress. [ABSTRACT FROM AUTHOR]

An in vitro evaluation system of food texture was developed using artificial tongue and a conventional uniaxial compression apparatus to mimic the tongue-palate compression. Deformation behavior of agar gels on artificial tongues from silicone rubber with three levels of elastic modulus was observed during compression by a nondeformable plate. The results were compared with the oral strategy for size reduction from sensory evaluation by human subjects. Agar gels fractured upon compression when the strain of the gels was larger than that of artificial tongue, whereas they did not when the strain of the gels was equivalent to or smaller than that of the artificial tongue. When apparent elastic modulus of artificial tongue was approximately 5.5 × 104 Pa, fracture profile of the gels corresponded well to human tests. Results suggest that the oral strategy for size reduction might be determined by sensing the relative strain of the gels to the tongue during compression to a somewhat small strain. Practical Applications In an aged society, there is an increasing demand for properly texturized foods for safe consumption by those who have mastication or chewing difficulty. Food of soft texture is often preferred by these people because of easy tongue-palate compression and no need of the teeth mastication. An in vitro evaluation system of food texture developed in the present study provides a simple method for food manufactures in assessing textural acceptability of products without using human subjects. This evaluation system can lead to the innovation of food product design for textural diversity and thus improved quality of life for these disadvantaged populations. [ABSTRACT FROM AUTHOR]

Abstract: Gelation behavior of sodium alginate was investigated in an aqueous system at various CaCO3 doses using two alginate samples of different mannuronate (M)/guluronate (G) ratios but with comparable molecular masses. Macroscopic rheological properties of the polysaccharide were discussed during gelation in relation to microscopic supermolecular structures imaged by atomic force microscopy and Ca2+ binding. At fixed concentrations of the polysaccharide (0.5 w/v%) and glucono-δ-lactone (15mM) as an acidic material, the G-rich sample was higher in elasticity with rod-like molecular assemblies at the highest CaCO3 dose; 15mM, while the M-rich sample was higher in elasticity with network-like molecular assemblies at the lowest CaCO3 dose; 3.75mM. Gelation behavior near the sol-to-gel transition was generally described by the percolation model, except for the M-rich sample at the lowest CaCO3 dose. A critical CaCO3 dose corresponded to 7.5mM at which both alginate samples showed essentially the same gelation kinetics. In an equilibrium state, it was estimated that the G-rich sample was bound to larger amount of Ca2+ at the lowest CaCO3 dose, while the M-rich sample was bound to larger amount of Ca2+ at the highest CaCO3 dose. The amount of bound Ca2+ did not directly relate to elasticity of the system. Based on these results, dominant block structures are suggested for gelation. [Copyright &y& Elsevier]

Background: Recent anatomical studies have reported the feasibility of the endoscopic endonasal approach to the middle fossa. However, its clinical applicability has been discussed in only a few cases. This article describes the case of a middle fossa epidural abscess successfully drained through a fully endoscopic endonasal corridor and discusses the key technical points., Observations: The authors describe an 8-year-old boy who presented with worsening headache, fatigue, emesis, and fever and was diagnosed with a left middle fossa epidural abscess associated with sphenoid sinusitis. Following endoscopic sinus surgery performed by a rhinologist, the middle fossa was accessed by removing the maxillary strut through the transmaxillary transpterygoid corridor. Complete drainage of the abscess was confirmed on postoperative magnetic resonance imaging. The patient tolerated the surgery without neurological deficit and demonstrated prompt symptom improvement. He was discharged home after completing a 6-week course of antibiotic therapy and remained free from recurrence at 1 year following surgery., Lessons: The endoscopic endonasal approach may be applicable to a middle fossa epidural abscess, resulting in prompt clinical improvement. The maxillary strut is a key structure for entering the middle fossa. https://thejns.org/doi/10.3171/CASE24288.

Background: There is no clear objective indicator for selecting soft foods that are required for food bolus formation in older people with impaired oral function., Objective: This study aimed to investigate the relationship between maximal isometric tongue pressure (MITP) and the mechanical properties of gels that can be crushed by the tongue., Methods: This study included 65 healthy participants aged 22-96 (young group; 15 males, 15 females; older dentate group; 7 males, 8 females; older edentulous group; 10 males, 10 females). MITP was measured by the balloon-probe device. Agar gel with 10 different kinds of fracture force from 10N to 100N was used. The limit of fracture force of gels (LFFG) that were crushed by the tongue was measured by the up-and-down method. In the older edentulous group, two items were measured with and without dentures. Spearman's rank correlation coefficient was used to evaluate the relationship between MITP and LFFG in each group (p < .05)., Results: There were positive correlations between MITP and LFFG in all groups (overall groups: r s  = .66, young group: r s  = .46, older dentate group: r s  = .61, older edentulous group with dentures: r s  = .60, older edentulous group without dentures: r s  = .47)., Conclusion: MITP and LFFG were positively correlated in young, older dentate and older edentulous groups, suggesting that MITP has the potential to be an objective indicator of the range of mechanical properties of soft food that can be crushed by the tongue., (© 2023 John Wiley & Sons Ltd.)

Background and Aims: To examine the roles of microRNAs in the development of colitis, we conducted the RNA-sequencing studies using RNA derived from normal and colitogenic CD4+ T cells. Colitogenic CD4 + T cells demonstrated the increased expression of miR-150. We focused on the involvement of miR-150 in the colitis., Methods: We crossed miR-150 knockout mice and T-cell-specific Rap1KO mice, which is colitis model mice and spontaneously develop the colitis with tubular adenomas in microbiota-dependent manner., Results: MiR-150 silencing completely inhibited the expansion of pathogenic Th17 cells and the development of colitis., Conclusion: MiR-150 is a potential therapeutic target of inflammatory bowel diseases., (© 2023 The Authors.)

Background: Acute encephalopathy with biphasic seizures and late reduced diffusion (AESD) and mild encephalopathy associated with excitotoxicity (MEEX) are the most frequent acute encephalopathies in pediatric patients in Japan. AESD typically presents with biphasic seizures and delayed reduced diffusion in the subcortical area, called bright tree appearance (BTA), on radiological examination. In patients with AESD, arterial spin labeling (ASL) shows decreased cerebral blood flow (CBF) in the hyperacute stage and increased CBF in the acute stage, suggesting the usefulness of ASL for the early diagnosis of AESD. Additionally, proton magnetic resonance spectroscopy (MRS) shows elevated glutamate (Glu) and glutamine (Gln) in AESD. MEEX is a group of mild encephalopathies with transient elevation of Gln on MRS similar to that in AESD; however, MEEX does not include any clinical biphasic course or abnormalities, including BTA on diffusion-weighted imaging. Although the usefulness of ASL for AESD has been reported, there are no reports for patients with MEEX. In this study, we report our experience with a 4-year-old girl diagnosed with MEEX who showed unique findings on ASL., Case Presentation: The patient was a 4-year-old girl admitted to the emergency room with febrile status epilepticus. Considering the possibility of AESD, vitamin therapy was initiated. ASL-MR imaging (MRI) of the brain performed on the second day showed increased blood flow in the frontal, temporal, and occipital regions with spared central sulcus, which indicated AESD with central sparing. The patient was diagnosed with AESD, and the treatment included pulse steroid therapy and immunoglobulin therapy from day 3. The patient remained mildly unconscious but gradually became conscious by day 7 with no seizures. Brain MRI performed on day 8 did not show any characteristic AESD findings, such as BTA. Furthermore, MRS showed elevated Gln, which, along with the clinical course, led to the diagnosis of MEEX. The patient was discharged on day 16 without obvious sequelae., Conclusions: ASL may be useful in the early diagnosis of MEEX as well as AESD, facilitating early intervention., (© 2022. The Author(s).)

T-cell-specific Rap1 deletion causes spontaneous colitis in mice. In the present study, we revealed that Rap1 deficiency in T cells impaired the preceding induction of intestinal RORγt + Treg cells. In the large intestinal lamina propria (LILP) of T-cell-specific Rap1-knockout mice (Rap1KO mice), Th17 cells were found to increase in a microbiota-dependent manner, and the inhibition of IL-17A production prevented the development of colitis. In the LILP of Rap1KO mice, RORγt + Treg cells were scarcely induced by 4 weeks of age. The expression of CTLA-4 on Rap1-deficient Treg cells was reduced and the expression of CD80 and CD86 on dendritic cells was consequently elevated in Rap1KO mice. When cultured under each polarizing condition, Rap1-deficient naïve CD4 + T cells did not show biased differentiation into Th17 cells; their differentiation into Treg cells as well as Th1 and Th2 cells was lesser than that of wild-type cells. Rap1-deficient naïve CD4 + T cells were found to exhibit the defective nuclear translocation of NFAT and formation of actin foci in response to TCR engagement. These data suggest that Rap1 amplifies the TCR signaling required for Treg-mediated control of intestinal colitogenic Th17 responses., (© 2022. The Author(s).)

Integrin activation is associated with conformational regulation. In this study, we developed a system to evaluate conformational changes in α 4 β 7 integrin. We first inserted the PA tag into the plexin-semaphorin-integrin (PSI) domain of β 7 chain, which reacted with an anti-PA tag antibody (NZ-1) in an Mn 2+ -dependent manner. The small GTPase Rap1 deficiency, as well as chemokine stimulation and the introduction of the active form of Rap1, Rap1V12, enhanced the binding of NZ-1 to the PA-tagged mutant integrin, and increased the binding affinity to mucosal addressing cell adhesion molecule-1 (MAdCAM-1). Furthermore, we generated two kinds of hybridomas producing monoclonal antibodies (mAbs) that recognized Mn 2+ -dependent epitopes of β 7 . Both epitopes were exposed to bind to mAbs on the cells by the introduction of Rap1V12. Although one epitope in the PSI domain of β 7 was exposed on Rap1-deficienct cells, the other epitope in the hybrid domain of β 7 was not. These data indicate that the conversion of Rap1-GDP to GTP exerts two distinct effects stepwise on the conformation of α 4 β 7 . The induction of colitis by Rap1-deficient CD4 + effector/memory T cells suggests that the removal of constraining effect by Rap1-GDP on α 4 β 7 is sufficient for homing of these pathogenic T cells into colon lamina propria (LP).

Background: Lymphocytes circulate between peripheral lymphoid tissues via blood and lymphatic systems, and chemokine-induced migration is important in trafficking lymphocytes to distant sites. The small GTPase Rap1 is important in mediating lymphocyte motility, and Rap1-GEFs are involved in chemokine-mediated Rap1 activation. Here, we describe the roles and mechanisms of Rap1-GEFs in lymphocyte trafficking., Results: In this study, we show that RA-GEF-1 and 2 (also known as Rapgef2 and 6) are key guanine nucleotide exchange factors (GEF) for Rap1 in lymphocyte trafficking. Mice harboring T cell-specific knockouts of Rapgef2/6 demonstrate defective homing and egress of T cells. Sphingosine-1-phosphate (S1P) as well as chemokines activates Rap1 in a RA-GEF-1/2-dependent manner, and their deficiency in T cells impairs Mst1 phosphorylation, cell polarization, and chemotaxis toward S1P gradient. On the other hand, B cell-specific knockouts of Rapgef2/6 impair chemokine-dependent retention of B cells in the bone marrow and passively facilitate egress. Phospholipase D2-dependent production of phosphatidic acid by these chemotactic factors determines spatial distribution of Rap1-GTP subsequent to membrane localization of RA-GEFs and induces the development of front membrane. On the other hand, basal de-phosphorylation of RA-GEFs is necessary for chemotactic factor-dependent increase in GEF activity for Rap1., Conclusions: We demonstrate here that subcellular distribution and activation of RA-GEFs are key factors for a directional movement of lymphocytes and that phosphatidic acid is critical for membrane translocation of RA-GEFs with chemokine stimulation.

Introduction: Collagen peptides have been widely used as a food supplement. After ingestion of collagen peptides, oligopeptides containing hydroxyproline (Hyp), which are known to have some physiological activities, are detected in peripheral blood. However, the effects of collagen-peptide administration on immune response are unclear. In the present study, we tested the effects of collagen-peptide ingestion on allergic response and the effects of collagen-derived oligopeptides on CD4 + T-cell differentiation., Methods: BALB/c mice fed a collagen-peptide diet were immunized with ovalbumin (OVA), and their serum IgE and IgG levels, active cutaneous anaphylaxis, and cytokine secretion by splenocytes were examined. Naive CD4 + T cells were stimulated with anti-CD3 and anti-CD28 in the presence of collagen-derived oligopeptides, and the expression of IFN-γ, IL-4, and Foxp3 was analyzed., Results: In an active anaphylaxis model, oral administration of collagen peptides suppressed serum OVA-specific immunoglobulin E (IgE) production and diminished anaphylaxis responses. In this model, the ingestion of collagen peptides skewed the pattern of cytokine production by splenocytes toward T-helper (Th) type 1 and regulatory T (Treg) cells. In vitro T-helper cell differentiation assays showed that Hyp-containing oligopeptides promoted Th1 differentiation by upregulating IFN-γ-induced signal transducer and activator of transcription 1 (STAT1) signaling. These oligopeptides also promoted the development of Foxp3 + Treg cells in response to antigen stimulation in the presence of TGF-β., Conclusions: Collagen-peptide ingestion suppresses allergic responses by skewing the balance of CD4 + T cells toward Th1 and Treg cells and seems to be a promising agent for preventing allergies and inflammatory diseases., (© 2018 The Authors. Immunity, Inflammation and Disease Published by John Wiley & Sons Ltd.)

This paper proposes a novel texture sensing method for nursing-care gel by using an artificial mastication system, in which not only mechanical characteristics but also geometrical ones are objectively and quantitatively evaluated. When human masticates gel food, she or he perceives the changes of the shape and contact force simultaneously. Based on the impressions, they evaluate the texture. For reproducing such a procedure, the pressure distribution of gel is measured in the simple artificial mastication, and the information associated to both the geometrical and mechanical characteristics is simultaneously acquired. The relationship between the value of sensory evaluation (i.e. impression human perceives), and the pressure distribution data is numerically modeled by applying the image texture analysis. Experimental results show that the proposed method succeeds in estimating the values of sensory evaluation of nine kinds of gel with the coefficient of determination greater than 0.93.

Semisynthetic cephalosporins, the best-selling antibiotics worldwide, are derived from 7-aminocephalosporanic acid (7-ACA). Currently, in the pharmaceutical industrie, 7-ACA is mainly produced from cephalosporin C by sequential application of D-amino acid oxidase and cephalosporin acylase. Here we study the potential of industrially amenable enzyme gamma-glutamyltranspeptidase from Bacillus subtilis for 7-ACA production, since the wild-type gamma-glutamyltranspeptidase of B. subtilis has inherent glutaryl-7-aminocephalosporanic acid acylase activity with a k(cat) value of 0.0485 s(-1). Its activity has been enhanced by site directed and random mutagenesis. The k(cat)/K(m) value was increased to 3.41 s(-1) mM(-1) for a E423Y/E442Q/D445N mutant enzyme and the kcat value was increased to 0.508 s(-1) for a D445G mutant enzyme. Consequently, the catalytic efficiency and the turnover rate were improved up to about 1000-fold and 10-fold, compared with the wildtype gamma-glutamyltranspeptidase of B. subtilis.