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Cashew apple is a pseudo-fruit available abundantly during harvest seasons (March to July) and majority of them goes as waste because of their perishability and poor shelf life. However, the absence of distinct exocarp and seeds are some of the potential advantages for processing utility. Hence, in the present study, osmo-dehydrated products were prepared from two maturity stages i.e. breaker and ripe stages using sugar, spice mixture and were referred to as cashew fig and chew, respectively. The drying efficiency and product recovery were conquered by cashew chew and fig, respectively. Based on the biochemical and organoleptic qualities, ripe fruits were found suitable for preparation of chew and fig. The tannin content responsible for acridity got reduced (chew of ripe stage 1.18 to 0.53 mg/g and chew of breaker stage 1.85 to 0.68 mg/g) during the process of osmodehydration. Excluding total antioxidant activity, all other biochemical properties were found to be improved compared to their respective controls. [ABSTRACT FROM AUTHOR]

In the present study a comprehensive protocol to assess chewing in four children with Down syndrome is provided and described. One baseline and four assessment meals were conducted across four textures of foods to investigate the presence or absence of components of chewing (bite down, chew and tongue lateralization), as well as movements associated with the development of chewing. Results showed that at baseline all participants ate their typical diet (i.e., pureed food) but no chewing components or movements were observed. The findings of the assessment protocol indicated that it offers a prescriptive assessment of chewing and its components across different food textures. The results of the assessment provided useful information for clinicians by identifying a potential starting point for interventions to address chewing deficits. Furthermore, the findings add to the existing literature on the role of tongue lateralization and specific tongue movements in chewing. Implications of the findings for chewing interventions and future research are discussed. [ABSTRACT FROM AUTHOR]

The ability to control locomotion in a dynamic environment provides a competitive advantage for microorganisms, thus driving the evolution of sophisticated regulatory systems. In total, 19 known categories of chemotaxis systems control motility mediated by flagella or Type IV pili, plus other cellular functions. A key feature that distinguishes chemotaxis systems from generic two‐component regulatory systems is separation of receptor and kinase functions into distinct proteins, linked by CheW scaffold proteins. This arrangement allows for formation of varied arrays with remarkable signaling properties. We recently analyzed sequences of CheW‐like domains found in CheA kinases and CheW and CheV scaffold proteins. In total, 16 Architectures of CheA, CheW, and CheV proteins contain ~94% of all CheW‐like domains and form six Classes with likely functional specializations. We surveyed chemotaxis system categories and proteins containing CheW‐like domains in ~1900 prokaryotic species, the most comprehensive analysis to date, revealing new insights. Co‐occurrence analyses suggested that many chemotaxis systems occur in non‐random combinations within species, implying synergy or antagonism. Furthermore, many Architectures of proteins containing CheW‐like domains occurred predominantly with specific categories of chemotaxis systems, suggesting specialized functional interactions. We propose Class 1 (~80%) and Class 6 (~20%) CheW proteins exhibit preferences for distinct chemoreceptor structures. Furthermore, rare (~1%) Class 2 CheW proteins frequently co‐occurred with methyl‐accepting coiled coil proteins, which contain both receptor and kinase functions and so do not require connection via a CheW scaffold but may benefit from arrays. Last, rare multidomain CheW proteins may interact with different receptors than single‐domain CheW proteins. [ABSTRACT FROM AUTHOR]

Distinct brain regions are known to be associated with various emotional states. Cortical activity may be modulated by emotional states that are triggered by flavors during food intake. We examined cortical activity during chewing with different flavors and assessed the emotional modulation of cortical activity using multichannel near-infrared spectroscopy. Thirty-six right-handed volunteers participated in this crossover trial. The participants experienced positive and negative emotions from chewing flavorful (palatable) or less flavorful (unpalatable) gums, respectively for 5 min. Participants rated the taste, odor, and deliciousness of each gum using a visual analog scale. Bilateral hemodynamic responses in the frontal and parietal lobes, bilateral masseter muscle activation, and heart rate were measured during gum chewing. Changes in all measured data during gum chewing were also evaluated. The ratings of the tastes and odors of each gum significantly differed among the participants (P < 0.001). Hemodynamic response changes were significantly elevated in the bilateral primary sensorimotor cortex during gum-chewing, in comparison to resting. The difference in hemodynamic responses between palatable and unpalatable gum conditions was detected in the left frontopolar/dorsolateral prefrontal cortex. Muscle activation and heart rate were not significantly different between different gum types. Our findings indicate that differential processing in the left prefrontal cortex might be responsible for the emotional states caused by palatable and unpalatable foods. [ABSTRACT FROM AUTHOR]

Domains are the three‐dimensional building blocks of proteins. An individual domain can occur in a variety of domain architectures that perform unique functions and are subject to different evolutionary selective pressures. We describe an approach to evaluate the variability in amino acid sequences of a single domain across architectural contexts. The ability to distinguish different evolutionary outcomes of one protein domain can help determine whether existing knowledge about a specific domain will apply to an uncharacterized protein, lead to insights and hypotheses about function, and guide experimental priorities. We developed and tested our approach on CheW‐like domains (PF01584), which mediate protein/protein interactions and are difficult to compare experimentally. CheW‐like domains occur in CheW scaffolding proteins, CheA kinases, and CheV proteins that regulate bacterial chemotaxis. We analyzed 16 domain architectures that included 94% of all CheW‐like domains found in nature. We identified six Classes of CheW‐like domains with presumed functional differences. CheV and most CheW proteins contained Class 1 domains, whereas some CheW proteins contained Class 6 (~20%) or Class 2 (~1%) domains instead. Most CheA proteins contained Class 3 domains. CheA proteins with multiple Hpt domains contained Class 4 domains. CheA proteins with two CheW‐like domains contained one Class 3 and one Class 5. We also created SimpLogo, an innovative method for visualizing amino acid composition across large sets of multiple sequence alignments of arbitrary length. SimpLogo offers substantial advantages over standard sequence logos for comparison and analysis of related protein sequences. The R package for SimpLogo is freely available. [ABSTRACT FROM AUTHOR]

The purpose of this research is to examine conceptual metaphors with BITE and CHEW in two typologically different languages, English and Korean (BITE and CHEW in English and MWUL- ‘BITE’ and SSIP- ‘CHEW’ in Korean). There has been some research on conceptual metaphors with EAT and other words that depict general eating processes; however, little attention has been paid to conceptual metaphors with words that describe specific processes of eating events. This study first discusses key grammatical properties of BITE and CHEW and their conceptual metaphors in English and Korean based on an analysis of authentic corpus data. This study then shows that although the two verbs BITE and CHEW in each language can license some metaphors in common, overall they are more different than similar in terms of metaphor types, frequency distribution patterns, and preferred syntactic and semantic properties. This study further shows that although the pairs of the English verb and its Korean counterpart (i.e., BITE in English vs. MWUL- ‘BITE’ in Korean and CHEW in English vs. SSIP- ‘CHEW’ in Korean) can induce some conceptual metaphors in the same manner, their conceptual metaphors are also more different than similar with respect to metaphor types, frequency distribution patterns, and strong collocates. Taken together, the findings suggest that it is crucial to explore authentic uses of conceptual metaphors with specific verbs involved in eating processes in more detail across different languages, making use of attested corpus data, and that in this way we can make a significant contribution to the body of literature on conceptual metaphors. [ABSTRACT FROM AUTHOR]

While tobacco use nationwide is declining, smokeless tobacco (SLT) use remains steady, particularly among men in rural areas. Despite the harms of SLT, researchers know little about what initiates and sustains this use. In this study, we argue that SLT persistence is encouraged by its salience as an emblem of rural manhood. Based on interviews with 64 male and 19 female rural high school students we find that SLT symbolizes rural masculinity, and that many boys "spit and dip" to perform their status as rural men. We specify several peer, family, and community mechanisms that undergird this process. Finally, we discuss implications for men's health research and intervention efforts. [ABSTRACT FROM AUTHOR]

Background Limited evidence exists on the prevalence and social determinants of tobacco use in Afghanistan—a fragile post-war context where the tobacco epidemic is on the rise. This study aimed to estimate the prevalence and social determinants of tobacco use in Afghan men and women. Methods Data from the 2015 Afghanistan Demographic and Health Survey of 10 760 men and 29 461 women were used to generate weighted prevalence estimates for smoking, smokeless tobacco (SLT) products including chew and snuff tobacco, 'any tobacco use' and 'dual tobacco use'. We also modelled associations with tobacco outcomes using binary logistic regressions. Results We found that for men, smoking cigarettes was the most prevalent form of tobacco use (21.9% [95% confidence interval {CI} 21.2–22.7]). Prevalence rates were far lower for women, with cigarette/pipe smoking at 3.4% (95% CI 3.2–3.7). For both sexes, tobacco use was inversely associated with education and positively associated with agricultural and skilled and unskilled manual labour occupations. Wealth increased the odds of smoking for men but decreased the odds for women. Media exposure had little influence on tobacco use among women; however, the effects were more varied for men. Conclusions Our results demonstrate social inequalities in tobacco use among Afghan men and women, which calls for stronger tobacco control measures and continued monitoring of this growing epidemic. [ABSTRACT FROM AUTHOR]

Magnetospirillum gryphiswaldense employs iron-rich nanoparticles for magnetic navigation within environmental redox gradients. This behavior termed magnetoaerotaxis was previously shown to rely on the sensory pathway CheOp1, but the precise localization of CheOp1-related chemoreceptor arrays during the cell cycle and its possible interconnection with three other chemotaxis pathways have remained unstudied. Here, we analyzed the localization of chemoreceptor-associated adaptor protein CheW1 and histidine kinase CheA1 by superresolution microscopy in a spatiotemporal manner. CheW1 localized in dynamic clusters that undergo occasional segregation and fusion events at lateral sites of both cell poles. Newly formed smaller clusters originating at midcell before completion of cytokinesis were found to grow in size during the cell cycle. Bipolar CheA1 localization and formation of aerotactic swim halos were affected depending on the fluorescent protein tag, indicating that CheA1 localization is important for aerotaxis. Furthermore, polar CheW1 localization was independent of cheOp2 to cheOp4 but lost in the absence of cheOp1 or cheA1. Results were corroborated by the detection of a direct protein interaction between CheA1 and CheW1 and by the observation that cheOp2- and cheOp3-encoded CheW paralogs localized in spatially distinct smaller clusters at the cell boundary. Although the findings of a minor aerotaxis-related CheOp4 phenotype and weak protein interactions between CheOp1 and CheOp4 by two-hybrid analysis implied that CheW1 and CheW4 might be part of the same chemoreceptor array, CheW4 was localized in spatially distinct polar-lateral arrays independent of CheOp1, suggesting that CheOp1 and CheOp4 are also not connected at the molecular level. [ABSTRACT FROM AUTHOR]

Introduction The Florida Youth Tobacco Survey (FYTS) was administered in the spring of 2008 to 38,510 middle school students and 40,283 high school students in 744 public schools throughout the state. The survey response rate for middle schools was 79%, and the survey response rate for high schools was 73%. The FYTS has been conducted annually since 1998. The data presented in this fact sheet are weighted to represent the entire population of public middle and high school students in Florida.

The present study was aimed at assessing the ingestive behavior of ¾ Zebu × Holstein heifers confined to different levels of substitution of sorghum silage by marandu grass silage. Twenty heifers were used with initial average weight of 346.25 kg, divided into completely randomized experimental design with 5 repetitions and the following treatments: treatment 1) roughage fraction of the diet composed of 100% of sorghum silage; treatment 2) roughage fraction of the diet composed of 70% of sorghum silage and 30% of marandu grass silage; treatment 3) roughage fraction of the diet composed of 30% of sorghum silage and 70% of marandu grass silage and treatment 4) roughage fraction of the diet composed of 100% of marandu grass silage. Concentrate was provided (25.25% soybean meal, 73.44% ground corn and 1.31% mineral mixture, based on natural matter), made calculations for ingestion of 1.2% of the live weight. Visual observations were accomplished for determination of ingestive behavior, every 21 days. The substitution of sorghum silage by marandu grass silage increased time with feeding, it did not affect time with rumination, time of chew, number of chews a day nor number of meals a day, but it resulted in lower feed efficiency, without interfering in the rumination efficiency of dry matter (DM) and neutral detergent insoluble fiber (NDF). [ABSTRACT FROM AUTHOR]

Chew, written by John Layman and drawn by Rob Guillory, is a disgusting comic. Yet that is precisely its appeal. This article begins with the paradox of aversion, a question drawn from the realm of aesthetic theory, to ask why readers made a bestseller of this comic about a cannibal cop. A close textual analysis of Chew shows how Layman and Guillory use the possibilities and constraints of the medium of comics, along with a substantial infusion of humour, to skilfully deploy the simultaneous attraction and repulsion inherent in disgust. The article then argues that the comic effectively challenges the functions of moral disgust. Chew implicitly undermines the racist discourses associated with Asians and food in the West, and it suggests that cannibalism can serve as an acceptable manner of gaining information and of communing with the dead. Chew's balance between the visceral repulsion and fascination of the disgusting, its humorous play at the borders of cultural transgression, and the narrative necessity of disgusting actions results in a meaningful and highly entertaining engagement with the aesthetics and politics of disgust that redraws the boundaries of what is fit for human consumption. [ABSTRACT FROM AUTHOR]

Objective Some crush-resistant tablet formulations (CRTs) reduce prescription opioid abuse by nonoral routes of administration (ROAs), especially insufflation and injection, while oral abuse increases. Oral abuse involving product manipulation vs swallowing whole for CRTs and comparators was examined. Methods Abuse by oral modes of administration (e.g. swallowing whole, chewing, dissolving in the mouth), was examined using the ASI-MV, a computerized, clinical interview for adults in substance abuse treatment from January 2009 to March 2015. CRTs (reformulated oxycodone extended-release [ER], reformulated oxymorphone ER, and tapentadol ER) were compared with non-CRT versions, morphine ER, and oxycodone immediate-release single entity. Analyses employed descriptive statistics and logistic regression. Results Among 364,329 unique assessments, 18,135 patients reported oral abuse of the CRTs and comparators examined. CRTs had a higher prevalence of oral abuse involving product manipulation than comparators (P  < 0.0001) among all abusers of product. Oral abuse involving product manipulation for CRTs was greater among the subset of patients reporting oral abuse and significantly higher than comparators (P  < 0.003). CRTs were significantly less likely than comparators to be swallowed whole (P  < 0.0001) and significantly more likely to be chewed (P  < 0.003). CRTs were more likely to be dissolved in the mouth than most comparators. Conclusions Results suggest the need for abuse-deterrent formulations designed to reduce abuse by oral administration with product manipulation, such as chewing. Advances in this area may reduce the overall abuse of prescription opioids and interrupt the progression from abuse by swallowing whole to oral administration involving product manipulation and other ROAs. [ABSTRACT FROM AUTHOR]

Copyright of Archives of Dental Science / Arquivos em Odontologia is the property of Universidade Federal de Minas Gerais, Faculdade de Odontologia and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

In addition to its role in DNA damage repair and recombination, the RecA protein, through its interaction with CheW, is involved in swarming motility, a form of flagella-dependent movement across surfaces. In order to better understand how SOS response modulates swarming, in this work the location of RecA and CheW proteins within the swarming cells has been studied by using super-resolution microscopy. Further, and after in silico docking studies, the specific RecA and CheW regions associated with the RecA-CheW interaction have also been confirmed by site-directed mutagenesis and immunoprecipitation techniques. Our results point out that the CheW distribution changes, from the cell poles to foci distributed in a helical pattern along the cell axis when SOS response is activated or RecA protein is overexpressed. In this situation, the CheW presents the same subcellular location as that of RecA, pointing out that the previously described RecA storage structures may be modulators of swarming motility. Data reported herein not only confirmed that the RecA-CheW pair is essential for swarming motility but it is directly involved in the CheW distribution change associated to SOS response activation. A model explaining not only the mechanism by which DNA damage modulates swarming but also how both the lack and the excess of RecA protein impair this motility is proposed.

For many vertebrate species, bite force plays an important functional role. Ecological characteristics of a species' niche, such as diet, are often associated with bite force. Previous evidence suggests a biomechanical trade-off between rodents specialized for gnawing, which feed mainly on seeds, and those specialized for chewing, which feed mainly on green vegetation. We tested the hypothesis that gnawers are stronger biters than chewers. We estimated bite force and measured skull and mandible shape and size in 63 genera of a major rodent radiation (the myomorph sigmodontines). Analysis of the influence of diet on bite force and morphology was made in a comparative framework. We then used phylogenetic path analysis to uncover the most probable causal relationships linking diet and bite force. Both granivores (gnawers) and herbivores (chewers) have a similar high bite force, leading us to reject the initial hypothesis. Path analysis reveals that bite force is more likely influenced by diet than the reverse causality. The absence of a trade-off between herbivores and granivores may be associated with the generalist nature of the myomorph condition seen in sigmodontine rodents. Both gnawing and chewing sigmodontines exhibit similar, intermediate phenotypes, at least compared to extreme gnawers (squirrels) and chewers (chinchillas). Only insectivorous rodents appear to be moving towards a different direction in the shape space, through some notable changes in morphology. In terms of diet, natural selection alters bite force through changes in size and shape, indicating that organisms adjust their bite force in tandem with changes in food items. [ABSTRACT FROM AUTHOR]

In addition to its role in DNA damage repair and recombination, the RecA protein, through its interaction with CheW, is involved in swarming motility, a form of flagelladependent movement across surfaces. In order to better understand how SOS response modulates swarming, in this work the location of RecA and CheW proteins within the swarming cells has been studied by using super-resolution microscopy. Further, and after in silico docking studies, the specific RecA and CheW regions associated with the RecA-CheW interaction have also been confirmed by site-directed mutagenesis and immunoprecipitation techniques. Our results point out that the CheW distribution changes, from the cell poles to foci distributed in a helical pattern along the cell axis when SOS response is activated or RecA protein is overexpressed. In this situation, the CheW presents the same subcellular location as that of RecA, pointing out that the previously described RecA storage structures may be modulators of swarming motility. Data reported herein not only confirmed that the RecA-CheW pair is essential for swarming motility but it is directly involved in the CheW distribution change associated to SOS response activation. A model explaining not only the mechanism by which DNA damage modulates swarming but also how both the lack and the excess of RecA protein impair this motility is proposed. [ABSTRACT FROM AUTHOR]

Distinct brain regions are known to be associated with various emotional states. Cortical activity may be modulated by emotional states that are triggered by flavors during food intake. We examined cortical activity during chewing with different flavors and assessed the emotional modulation of cortical activity using multichannel near-infrared spectroscopy. Thirty-six right-handed volunteers participated in this crossover trial. The participants experienced positive and negative emotions from chewing flavorful (palatable) or less flavorful (unpalatable) gums, respectively for 5 min. Participants rated the taste, odor, and deliciousness of each gum using a visual analog scale. Bilateral hemodynamic responses in the frontal and parietal lobes, bilateral masseter muscle activation, and heart rate were measured during gum chewing. Changes in all measured data during gum chewing were also evaluated. The ratings of the tastes and odors of each gum significantly differed among the participants ( P < 0.001). Hemodynamic response changes were significantly elevated in the bilateral primary sensorimotor cortex during gum-chewing, in comparison to resting. The difference in hemodynamic responses between palatable and unpalatable gum conditions was detected in the left frontopolar/dorsolateral prefrontal cortex. Muscle activation and heart rate were not significantly different between different gum types. Our findings indicate that differential processing in the left prefrontal cortex might be responsible for the emotional states caused by palatable and unpalatable foods., Competing Interests: 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., (Copyright © 2022 Hasegawa, Sakuramoto, Suzuki, Sakagami, Shiramizu, Tachibana, Kishimoto, Ono and Ono.)

Abstract: Chewing reportedly contributes to satiation and satiety signals. Attempts to document and quantify this have led to small and inconsistent effects. The present trial manipulated oral processing effort though required chewing of gums of different hardness and measured appetitive sensations, energy intake, gastric emptying, GI transit time, and concentrations of glucose, insulin, GLP-1, ghrelin and pancreatic polypeptide. Sixty adults classified by sex and BMI (15 each of lean females, obese females, lean males and obese males) were tested in a randomized, controlled, cross-over trial with three arms. They chewed nothing, soft gum or hard gum for 15min while sipping grape juice (10% of individual energy needs) containing acetaminophen and lactulose on one day each separated by 7days. Electromyographic recordings and self-reports were obtained during and after chewing to quantify oral processing effort. Blood was sampled through an indwelling catheter and appetite ratings were obtained at baseline and at 0, 15, 30, 45, 60, 90, 120, 180 and 240min after chewing initiation. Breath samples were collected at 10min intervals for the first 2h and at 30min intervals for the next 2h. No effects of chewing were observed for appetitive sensations or gut peptide concentrations. Energy intake tended to decline in lean and increase in obese participants so that daily energy intake differed significantly between the two groups when chewing either gum, while no difference was observed on the non-chewing day. Serum glucose and insulin were significantly lower at selected time points 90–240min after chewing compared to baseline and the non-chewing day. These data indicate chewing effort does not affect appetitive sensations or gut peptide secretion, but may exert a small differential effect on acute energy intake in lean and obese individuals and lead to greater post-prandial declines of serum glucose and insulin. The efficacy of gum chewing as a substitute for eating for weight management remains uncertain. [Copyright &y& Elsevier]

Abstract: The basic structural unit of the signaling complex in bacterial chemotaxis consists of the chemotaxis kinase CheA, the coupling protein CheW, and chemoreceptors. These complexes play an important role in regulating the kinase activity of CheA and in turn controlling the rotational bias of the flagellar motor. Although individual three-dimensional structures of CheA, CheW, and chemoreceptors have been determined, the interaction between chemoreceptor and CheW is still unclear. We used nuclear magnetic resonance to characterize the interaction modes of chemoreceptor and CheW from Thermotoga maritima. We find that chemoreceptor binding surface is located near the highly conserved tip region of the N-terminal helix of the receptor, whereas the binding interface of CheW is placed between the β-strand 8 of domain 1 and the β-strands 1 and 3 of domain 2. The receptor–CheW complex shares a similar binding interface to that found in the “trimer-of-dimers” oligomer interface seen in the crystal structure of cytoplasmic domains of chemoreceptors from Escherichia coli. Based on the association constants inferred from fast exchange chemical shifts associated with receptor–CheW titrations, we estimate that CheW binds about four times tighter to its first binding site of the receptor dimer than to its second binding site. This apparent anticooperativity in binding may reflect the close proximity of the two CheW binding surfaces near the receptor tip or further, complicating the events at this highly conserved region of the receptor. This work describes the first direct observation of the interaction between chemoreceptor and CheW. [Copyright &y& Elsevier]

Abstract: The bacterial chemotaxis adaptor protein CheW physically links the chemoreceptors (MCPs) and the histidine kinase CheA. Extensive investigations using bacterium Escherichia coli have established the central role of CheW in the MCP-modulated activation of CheA. Here we report the solution structure of CheW from E. coli determined by NMR spectroscopy. The results show that E. coli CheW shares an overall fold with previously reported structure of CheW from Thermotoga maritima, whereas local conformational deviations are observed. In particular, the C-terminal α-helix is considerably longer in E. coli CheW and appears to shrink the active binding pocket with CheA. Our study provides the structural basis for further investigations in E. coli chemotaxis. [Copyright &y& Elsevier]

The motility and chemotaxis systems are critical for the virulence of leptospires. In this study, the phylogenetic profiles method was used to predict the interaction of chemotaxis proteins. It was shown that CheW1 links to CheA1, CheY, CheB and CheW2; CheW3 links to CheA2, MCP (LA2426), CheB3 and CheD1; and CheW2 links only to CheW1. The similarity analysis demonstrated that CheW2 of Leptospira interrogans strain Lai had poor homology with CheW of Escherichia coli in the region of residues 30–50. In order to verify the function of these proteins, the putative che W genes were cloned into pQE31 vector and expressed in wild-type E. coli strain RP437 or che W defective strain RP4606. The swarming results indicated that CheW1 and CheW3 could restore swarming of RP4606 while CheW2 could not. Overexpression of CheW1 and CheW3 in RP437 inhibited the swarming of RP437, whereas the inhibitory effect of CheW2 was much lower. Therefore, we presumed that CheW1 and CheW3 might have the function of CheW while CheW2 does not. The existence of multiple copies of chemotaxis homologue genes suggested that L. interrogans strain Lai might have a more complex chemosensory pathway. Edited by Ming-Hua XU [ABSTRACT FROM AUTHOR]

Measurements of the 15N relaxation parameters have been used to characterize the backbone dynamics of CheW from Thermotoga maritima. The dynamic nature of residues that appeared disordered in our recent solution structure of CheW is confirmed by these dynamics measurements. We have interpreted the data in terms of the Lipari and Szabo ‘model-free’ approach. The derived order parameter, S2, the {1H}–15N heteronuclear nuclear Overhauser effect (NOE) values, the chemical exchange rate, Rex, and the internal correlation time, τe, show that CheW exhibits considerable motional freedom from the picosecond to millisecond time scales. These regions of the protein cluster within the framework of the three-dimensional structure and may indicate possible binding sites for other protein components of the bacterial chemotaxis receptor-signaling complex. The structure of CheW consists of two five-stranded β-barrel domains that pack together with an extensive hydrophobic core between the domains. Regions highlighted by dynamics measurements co-localize to specific regions of the three-dimensional structure of CheW previously implicated in the formation of bacterial chemotaxis receptor signaling complex. The motional properties of domain 2 of CheW suggest that this domain may be able to experience structural rearrangements that allow the exposure of a hydrophobic surface area that could be used as a binding surface for the other members of the receptor complex. Residues within domain 2 have been implicated in binding interactions for two chemotaxis proteins, CheA and the receptor. We further propose that domain 1 interacts with other components of the chemotaxis machinery, such as CheZ, or in the formation of clusters of signaling components. [Copyright &y& Elsevier]

Background: It has been widely recognized that mastication behaviors are related to the health of the whole body and to lifestyle-related diseases. However, many studies were based on subjective questionnaires or were limited to small-scale research in the laboratory due to the lack of a device for measuring mastication behaviors during the daily meal objectively. Recently, a small wearable masticatory counter device, called bitescan (Sharp Co), for measuring masticatory behavior was developed. This wearable device is designed to assess objective masticatory behavior by being worn on the ear in daily life., Objective: This study aimed to investigate the relation between mastication behaviors in the laboratory and in daily meals and to clarify the difference in mastication behaviors between those with metabolic syndrome (MetS) and those without (non-MetS) measured using a wearable device., Methods: A total of 99 healthy volunteers (50 men and 49 women, mean age 36.4 [SD 11.7] years) participated in this study. The mastication behaviors (ie, number of chews and bites, number of chews per bite, and chewing rate) were measured using a wearable ear-hung device. Mastication behaviors while eating a rice ball (100 g) in the laboratory and during usual meals for an entire day were monitored, and the daily energy intake was calculated. Participants' abdominal circumference, fasting glucose concentration, blood pressure, and serum lipids were also measured. Mastication behaviors in the laboratory and during meals for 1 entire day were compared. The participants were divided into 2 groups using the Japanese criteria for MetS (positive/negative for MetS or each MetS component), and mastication behaviors were compared., Results: Mastication behaviors in the laboratory and during daily meals were significantly correlated (number of chews r=0.36; P<.001; number of bites r=0.49; P<.001; number of chews per bite r=0.33; P=.001; and chewing rate r=0.51; P<.001). Although a positive correlation was observed between the number of chews during the 1-day meals and energy intake (r=0.26, P=.009), the number of chews per calorie ingested was negatively correlated with energy intake (r=-0.32, P=.002). Of the 99 participants, 8 fit the criteria for MetS and 14 for pre-MetS. The number of chews and bites for a rice ball in the pre-MetS(+) group was significantly lower than the pre-MetS(-) group (P=.02 and P=.04, respectively). Additionally, scores for the positive abdominal circumference and hypertension subgroups were also less than the counterpart groups (P=.004 and P=.01 for chews, P=.006 and P=.02 for bites, respectively). The number of chews and bites for an entire day in the hypertension subgroup were significantly lower than in the other groups (P=.02 and P=.006). Furthermore, the positive abdominal circumference and hypertension subgroups showed lower numbers of chews per calorie ingested for 1-day meals (P=.03 and P=.02, respectively)., Conclusions: These results suggest a relationship between masticatory behaviors in the laboratory and those during daily meals and that masticatory behaviors are associated with MetS and MetS components., Trial Registration: University Hospital Medical Information Network Clinical Trials Registry R000034453; https://tinyurl.com/mwzrhrua., (©Fumiko Uehara, Kazuhiro Hori, Yoko Hasegawa, Shogo Yoshimura, Shoko Hori, Mari Kitamura, Kohei Akazawa, Takahiro Ono. Originally published in JMIR mHealth and uHealth (https://mhealth.jmir.org), 24.03.2022.)

Chemotaxis responses of Escherichia coli and Salmonella are mediated by type I membrane receptors with N-terminal extracytoplasmic sensing domains connected by transmembrane helices to C-terminal signaling domains in the cytoplasm. Receptor signaling involves regulation of an associated protein kinase, CheA. Here we show that kinase activation by a soluble signaling domain construct involves the formation of a large complex, with ∼14 receptor signaling domains per CheA dimer. Electron microscopic examination of these active complexes indicates a well defined bundle composed of numerous receptor filaments. Our findings suggest a mechanism for transmembrane signaling whereby stimulus-induced changes in lateral packing interactions within an array of receptor-sensing domains at the cell surface perturb an equilibrium between active and inactive receptor­kinase complexes within the cytoplasm. [ABSTRACT FROM AUTHOR]

The CheW protein plays a key role in bacterial chemotaxis signal transduction by coupling CheA to chemotaxis receptors. CheW from Thermotoga maritima has been overexpressed in Escherichia coli and crystallized at 298 K using ammonium sulfate as a salt precipitant. X-ray diffraction data have been collected to 3.10 Å resolution at 100 K using synchrotron radiation. The crystal belonged to space group P63, with unit-cell parameters a = b = 61.265, c = 361.045 Å. The asymmetric unit may contain four to six CheW molecules. [ABSTRACT FROM AUTHOR]

Purpose: The aim of this study was to evaluate the effect of oral rehabilitation using immediately loaded fixed implant-supported mandibular prostheses, considering chewing, swallowing, speech and voice aspects. Material and methods: Fourteen patients subjected to this treatment were evaluated by a clinical examination of the stomatognathic system and perceptual evaluation of voice quality before oral rehabilitation, as well as after 1 and 4 months. Results: After oral rehabilitation, the results showed that there were no significant modifications in the aspects investigated. Conclusion: Thus, implant-supported prosthetic rehabilitation, despite providing a more satisfactory occlusal standard, did not yield changes in the functional patterns of individuals in this study. [ABSTRACT FROM AUTHOR]

Rabbits are the third most common mammalian pet in the United States. They make good pets because they generally are nonaggressive and are playful, active, and curious. They form strong social bonds, both with rabbits they live with in the household and with the humans who care for them. They have several behaviors derived from their wild counterparts that can cause problems, if not properly allowed for, or be beneficial, such as their proclivity to use a specific site for elimination., Competing Interests: Disclosure The author has nothing to disclose., (Copyright © 2020 Elsevier Inc. All rights reserved.)

Magnetospirillum gryphiswaldense employs iron-rich nanoparticles for magnetic navigation within environmental redox gradients. This behavior termed magneto-aerotaxis was previously shown to rely on the sensory pathway CheOp1, but the precise localization of CheOp1-related chemoreceptor arrays during the cell cycle and its possible interconnection with three other chemotaxis pathways have remained unstudied. Here, we analyzed the localization of chemoreceptor-associated adaptor protein CheW 1 and histidine kinase CheA 1 by superresolution microscopy in a spatiotemporal manner. CheW 1 localized in dynamic clusters that undergo occasional segregation and fusion events at lateral sites of both cell poles. Newly formed smaller clusters originating at midcell before completion of cytokinesis were found to grow in size during the cell cycle. Bipolar CheA 1 localization and formation of aerotactic swim halos were affected depending on the fluorescent protein tag, indicating that CheA 1 localization is important for aerotaxis. Furthermore, polar CheW 1 localization was independent of cheOp2 to cheOp4 but lost in the absence of cheOp1 or cheA 1 Results were corroborated by the detection of a direct protein interaction between CheA 1 and CheW 1 and by the observation that cheOp2 - and cheOp3 -encoded CheW paralogs localized in spatially distinct smaller clusters at the cell boundary. Although the findings of a minor aerotaxis-related CheOp4 phenotype and weak protein interactions between CheOp1 and CheOp4 by two-hybrid analysis implied that CheW 1 and CheW 4 might be part of the same chemoreceptor array, CheW 4 was localized in spatially distinct polar-lateral arrays independent of CheOp1, suggesting that CheOp1 and CheOp4 are also not connected at the molecular level. IMPORTANCE Magnetotactic bacteria (MTB) use the geomagnetic field for navigation in aquatic redox gradients. However, the highly complex signal transduction networks in these environmental microbes are poorly understood. Here, we analyzed the localization of selected chemotaxis proteins to spatially and temporally resolve chemotaxis array localization in Magnetospirillum gryphiswaldense Our findings suggest that bipolar localization of chemotaxis arrays related to the key signaling pathway CheOp1 is important for aerotaxis and that CheOp1 signaling units assemble independent of the three other chemotaxis pathways present in M. gryphiswaldense Overall, our results provide deeper insights into the complex organization of signaling pathways in MTB and add to the general understanding of environmental bacteria possessing multiple chemotaxis pathways., (Copyright © 2020 American Society for Microbiology.)

The objective of this study was to investigate the influence of daily feeding of an oral care chew on the composition of canine supragingival plaque microbiota. Twelve beagle dogs were recruited to the randomized cross-over study. The dogs were fed one of two dietary regimes, both consisting of a commercially available wet and dry diet mix, either with or without daily supplementation with an oral care chew. After each 28-day test phase, supragingival plaque samples were collected and processed via Illumina sequencing to determine the microbiota composition. A comparative analysis of bacterial species associated with health and periodontal disease, identified from prior clinical studies, revealed differences between the dietary regimes. Consumption of the daily oral care chew, resulted in a significant increase in proportion of 6 health associated taxa but only 3 disease associated taxa compared to no chew. In contrast, 8 disease and 1 health associated taxa showed increased proportions for no chew versus the oral care chew. Daily feeding of the oral care chew tested in this study has therefore been shown to increase the proportion of health associated bacteria, over bacteria associated with periodontal disease, in supragingival plaque compared to no chew. By influencing plaque microbiota towards a bias for health associated bacteria, feeding of the oral care chew provides a means to reduce the prevalence of bacterial species shown to be associated with periodontal disease in dogs., (Copyright © 2020 Elsevier Ltd. All rights reserved.)