Microbial transglutaminases (mTGs) belong to the family of global TGs, isolated and characterised by various bacterial strains, with the first being Streptomyces mobaraensis. This literature review also discusses TGs of animal and plant origin. TGs catalyse the formation of an isopeptide bond, cross-linking the amino and acyl groups. Due to its broad enzymatic activity, TG is extensively utilised in the food industry. The annual net growth in the utilisation of enzymes in the food processing industry is estimated to be 21.9%. As of 2020, the global food enzymes market was valued at around $2.3 billion USD (mTG market was estimated to be around $200 million USD). Much of this growth is attributed to the applications of mTG, benefiting both producers and consumers. In the food industry, TG enhances gelation and modifies emulsification, foaming, viscosity, and water-holding capacity. Research on TG, mainly mTG, provides increasing insights into the wide range of applications of this enzyme in various industrial sectors and promotes enzymatic processing. This work presents the characteristics of TGs, their properties, and the rationale for their utilisation. The review aims to provide theoretical foundations that will assist researchers worldwide in building a methodological framework and furthering the advancement of biotechnology research.

The CryoPreservation Media (CPM) for mouse sperm using raffinose and skim milk have been improved by adding either monothioglycerol (MTG) or l-glutamine to reduce the oxidative damage during sperm freezing and thawing. The CARD-CPM utilizing l-glutamine, but not MTG, has been widely used to meet the rising demand for cryopreservation of genetically modified mice, as the CARD method also improved sperm capacitation and in vitro fertilization (IVF). However, the viability of sperm frozen in the CARD-CPM is highly variable, indicating a room for improvement. To develop a more dependable technique for mouse sperm cryopreservation, we investigate whether combining MTG and l-glutamine in the CPM (MG-CPM) can produce a synergistic impact on sperm thawing and IVF rate. We found that MG-CPM reduced the incidence of infertility and increased the IVF success rate. Therefore, cryopreservation of mouse sperm in MG-CPM is a reliable method to ensure embryo generation from frozen sperm.

The middle temporal gyrus (MTG) is understood to play a role in language-related tasks such as lexical comprehension and semantic cognition. However, a more specific understanding of its key white matter connections could promote the preservation of these functions during neurosurgery.
To provide a detailed description of the underlying white matter tracts associated with the MTG to improve semantic preservation during neurosurgery.
Tractography was performed using diffusion imaging obtained from 10 healthy adults from the Human Connectome Project. All tracts were mapped between cerebral hemispheres with a subsequent laterality index calculated based on resultant tract volumes. Ten postmortem dissections were performed for ex vivo validation of the tractography based on qualitative visual agreement.
We identified 2 major white matter bundles leaving the MTG: the inferior longitudinal fasciculus and superior longitudinal fasciculus. In addition to long association fibers, a unique linear sequence of U-shaped fibers was identified, possibly representing a form of visual semantic transfer down the temporal lobe.
We elucidate the underlying fiber-bundle anatomy of the MTG, an area highly involved in the brain\'s language network. Improved understanding of the unique, underlying white matter connections in and around this area may augment our overall understanding of language processing as well as the involvement of higher order cerebral networks like the default mode network in these functions.

Injectable hydrogels can be useful tools for facilitating wound healing since they conform to the irregular shapes of wounds, serving as a temporary matrix during the healing process. However, the lack of inherent pore structures of most injectable hydrogels prohibits desired interactions with the cells of the surrounding tissues limiting their clinical efficacy. Here, we introduce a simple, cost-effective and highly biofunctional injectable macroporous hydrogel made of gelatin microgels crosslinked by microbial transglutaminase (mTG). Pores are created by the interstitial space among the microgels. A water-in-oil emulsion technique was used to create gelatin microgels of an average size of 250μm in diameter. When crosslinked with mTG, the microgels adhered to each other to form a bulk hydrogel with inherent pores large enough for cell migration. The viscoelastic properties of the porous hydrogel were similar to those of nonporous gelatin hydrogel made by adding mTG to a homogeneous gelatin solution. The porous hydrogel supported higher cellular proliferation of human dermal fibroblasts (hDFs) than the nonporous hydrogel over two weeks, and allowed the migration of hDFs into the pores. Conversely, the hDFs were unable to permeate the surface of the nonporous hydrogel. To demonstrate its potential use in wound healing, the gelatin microgels were injected with mTG into a cut out section of an excised porcine cornea. Due to the action of mTG, the porous hydrogel stably adhered to the cornea tissue for two weeks. Confocal images showed that a large number of cells from the cornea tissue migrated into the interstitial space of the porous hydrogel. The porous hydrogel was also used for the controlled release of platelet-derived growth factor (PDGF), increasing the proliferation of hDFs compared to the nonporous hydrogel. This gelatin microgel-based porous hydrogel will be a useful tool for wound healing and tissue engineering.

Previous electrophysiological work argues that predictability and semantic incongruity rapidly impact comprehension, as indicated by modulation of the N400 component between ~300 and 500 ms. An ongoing question is whether effects of predictability in fact reflect pre-activation in long-term memory as opposed to modulating the kind of integration processes triggered by incongruity. Using fMRI, we compared the impact of predictability and incongruity in adjective-noun phrases, in regions identified with lexical and phrasal localizer scans. We found that predictability impacted activity in left posterior middle temporal gyrus (pMTG), while incongruity impacted activity in left precentral gyrus. Together with parallel data from ERP, these data are consistent with the hypothesis that left pMTG activity is a key contributor to N400 effects of predictability and that the relevant mechanism is reduced activation of stored lexical representations. We tentatively suggest that the left precentral region may play a role in reanalysis when incongruity is encountered.

Valence is a dimension of emotion and can be either positive, negative, or neutral. Valences can be expressed through the visual and auditory modalities, and the valences of each modality can be conveyed by different types of stimuli (face, body, voice or music). This study focused on the modality-general representations of valences, that is, valence information can be shared across not only visual and auditory modalities but also different types of stimuli within each modality. Functional magnetic resonance imaging (fMRI) data were collected when subjects made affective judgment on silent videos (face and body) and audio clips (voice and music). The searchlight analysis helped to locate four areas that might be sensitive to the representations of modality-general valences, including the bilateral postcentral gyrus, left middle temporal gyrus (MTG) and right middle frontal gyrus (MFG). Further cross-modal classification based on multivoxel pattern analysis (MVPA) was performed as a validation analysis, which suggested that only the left postcentral gyrus could successfully distinguish three valences (positive versus negative and versus neutral: PvsNvs0) across different types of stimuli (face, body, voice or music), and the classification was also successful in left MTG across the stimuli types of face and body. The univariate analysis further found the valence-specific activation differences across stimulus types in MTG. Our study showed that the left postcentral gyrus was informative to valence representations, and extended the research about valence representation that the modality-general representation of valences across not only visual and auditory modalities but also different types of stimuli within each modality.

During public addresses, speakers accompany their discourse with spontaneous hand gestures (beats) that are tightly synchronized with the prosodic contour of the discourse. It has been proposed that speech and beat gestures originate from a common underlying linguistic process whereby both speech prosody and beats serve to emphasize relevant information. We hypothesized that breaking the consistency between beats and prosody by temporal desynchronization, would modulate activity of brain areas sensitive to speech-gesture integration. To this aim, we measured BOLD responses as participants watched a natural discourse where the speaker used beat gestures. In order to identify brain areas specifically involved in processing hand gestures with communicative intention, beat synchrony was evaluated against arbitrary visual cues bearing equivalent rhythmic and spatial properties as the gestures. Our results revealed that left MTG and IFG were specifically sensitive to speech synchronized with beats, compared to the arbitrary vision-speech pairing. Our results suggest that listeners confer beats a function of visual prosody, complementary to the prosodic structure of speech. We conclude that the emphasizing function of beat gestures in speech perception is instantiated through a specialized brain network sensitive to the communicative intent conveyed by a speaker with his/her hands.

The story-like organization of dreams is characterized by a pervasive bizarreness of events and actions that resembles psychotic thought, and largely exceeds that observed in normal waking fantasies. Little is known about the neural correlates of the confabulatory narrative construction of dreams. In this study, dreams, fantasies elicited by ambiguous pictorial stimuli, and non-imaginative first- and third-person narratives from healthy participants were recorded, and were then studied for brain blood oxygen level-dependent functional magnetic resonance imaging on a 3.0-Tesla scanner while listening to their own narrative reports and attempting a retrieval of the corresponding experience. In respect to non-bizarre reports of daytime activities, the script-driven recall of dreams and fantasies differentially activated a right hemisphere network including areas in the inferior frontal gyrus, and superior and middle temporal gyrus. Neural responses were significantly greater for fantasies than for dreams in all regions, and inversely proportional to the degree of bizarreness observed in narrative reports. The inferior frontal gyrus, superior and middle temporal gyrus have been implicated in the semantic activation, integration and selection needed to build a coherent story representation and to resolve semantic ambiguities; in deductive and inferential reasoning; in self- and other-perspective taking, theory of mind, moral and autobiographical reasoning. Their degree of activation could parallel the level of logical robustness or inconsistency experienced when integrating information and mental representations in the process of building fantasy and dream narratives.

Actions influence perceptions, but how this occurs may change across the lifespan. Studies have investigated how object-directed actions (e.g., learning about objects through manipulation) affect subsequent perception, but how abstract actions affect perception, and how this may change across development, have not been well studied. In the present study, we address this question, teaching children (4-7 year-olds) and adults sung melodies, with or without an abstract motor component, and using functional Magnetic Resonance Imaging (fMRI) to determine how these melodies are subsequently processed. Results demonstrated developmental change in the motor cortices and Middle Temporal Gyrus. Results have implications for understanding sensori-motor integration in the developing brain, and may provide insight into motor learning use in some music education techniques.

Myocardial ischemia/reperfusion (I/R) injury is a major clinical problem leading to cardiac dysfunction and myocyte death. It is widely held that I/R causes damage to membrane phospholipids, and is a significant mechanism of cardiac I/R injury. Molecular dissection of sarcolemmal damage in I/R, however, has been difficult to address experimentally. We studied here cardiac I/R injury under conditions targeting gain- or loss-of sarcolemma integrity. To implement gain-in-sarcolemma integrity during I/R, synthetic copolymer-based sarcolemmal stabilizers (CSS), including Poloxamer 188 (P188), were used as a tool to directly stabilize the sarcolemma. Consistent with the hypothesis of sarcolemmal stabilization, cellular markers of necrosis and apoptosis evident in untreated myocytes were fully blocked in sarcolemma stabilized myocytes. Unexpectedly, sarcolemmal stabilization of adult cardiac myocytes did not affect the status of myocyte-generated oxidants or lipid peroxidation in two independent assays. We also investigated the loss of sarcolemmal integrity using two independent genetic mouse models, dystrophin-deficient mdx or dysferlin knockout (Dysf KO) mice. Both models of sarcolemmal loss-of-function were severely affected by I/R injury ex vivo, and this was lessened by CSS. In vivo studies also showed that infarct size was significantly reduced in CSS-treated hearts. Mechanistically, these findings support a model whereby I/R-mediated increased myocyte oxidative stress is uncoupled from myocyte injury. Because the sarcolemma stabilizers used here do not transit across the myocyte membrane this is evidence that intracellular targets of oxidants are not sufficiently altered to affect cell death when sarcolemma integrity is preserved by synthetic stabilizers. These findings, in turn, suggest that sarcolemma destabilization, and consequent Ca(2+) mishandling, as a focal initiating mechanism underlying myocardial I/R injury.