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Tardigrades are microscopic animals that survive desiccation by inducing biostasis. To survive drying tardigrades rely on intrinsically disordered CAHS proteins, which also function to prevent perturbations induced by drying in vitro and in heterologous systems. CAHS proteins have been shown to form gels both in vitro and in vivo, which has been speculated to be linked to their protective capacity. However, the sequence features and mechanisms underlying gel formation and the necessity of gelation for protection have not been demonstrated. Here we report a mechanism of fibrillization and gelation for CAHS D similar to that of intermediate filament assembly. We show that in vitro, gelation restricts molecular motion, immobilizing and protecting labile material from the harmful effects of drying. In vivo, we observe that CAHS D forms fibrillar networks during osmotic stress. Fibrillar networking of CAHS D improves survival of osmotically shocked cells. We observe two emergent properties associated with fibrillization; (i) prevention of cell volume change and (ii) reduction of metabolic activity during osmotic shock. We find that there is no significant correlation between maintenance of cell volume and survival, while there is a significant correlation between reduced metabolism and survival. Importantly, CAHS Ds fibrillar network formation is reversible and metabolic rates return to control levels after CAHS fibers are resolved. This work provides insights into how tardigrades induce reversible biostasis through the self-assembly of labile CAHS gels.

Background: A concern with hierarchy messages, which promote male condoms and female-controlled barrier methods along a prevention continuum, is that they may discourage condom use.Goal: To measure male-condom and female-condom use among women who received hierarchy counseling and compare this with women counseled about condoms only.Study Design: Three observational cohorts that correspond to prevention message received were assembled, and consisted of female sexually transmitted disease clinic patients who were counseled about male condoms, female condoms, or a hierarchy message. The hierarchy message promoted male and female condoms, the diaphragm and cervical cap, spermicides, and withdrawal, in descending order of effectiveness against sexually transmitted diseases. After counseling, women were interviewed and returned for follow-up visits at 2 weeks, 4 months, and 6 months. The outcome was the mean proportion of male condom- or female condom-protected coital acts at each follow-up visit in the hierarchy cohort. The outcome was dichotomized as high (> or = 70% of coital acts protected) or low (< 70%), and generalized estimating equations were used to compare observed follow-up condom use with baseline within the hierarchy cohort and observed follow-up condom use between cohorts. It was assumed that condom use in persons not present at 6 months was equal to baseline levels, and condom use estimates were calculated for each full cohort that was initially enrolled. [ABSTRACT FROM AUTHOR]

Cellular desiccation - the loss of nearly all water from the cell - is a recurring stress in an increasing number of ecosystems that can drive protein unfolding and aggregation. For cells to survive, at least some of the proteome must resume function upon rehydration. Which proteins tolerate desiccation, and the molecular determinants that underlie this tolerance, are largely unknown. Here, we apply quantitative and structural proteomic mass spectrometry to show that certain proteins possess an innate capacity to tolerate rehydration following extreme water loss. Structural analysis points to protein surface chemistry as a key determinant for desiccation tolerance, which we test by showing that rational surface mutants can convert a desiccation sensitive protein into a tolerant one. Desiccation tolerance also has strong overlap with cellular function, with highly tolerant proteins responsible for production of small molecule building blocks, and intolerant proteins involved in energy-consuming processes such as ribosome biogenesis. As a result, the rehydrated proteome is preferentially enriched with metabolite and small molecule producers and depleted of some of the cell's heaviest consumers. We propose this functional bias enables cells to kickstart their metabolism and promote cell survival following desiccation and rehydration., Competing Interests: Competing Interests The authors declare that they have no competing interests.

The conformational ensemble and function of intrinsically disordered proteins (IDPs) are sensitive to their solution environment. The inherent malleability of disordered proteins combined with the exposure of their residues accounts for this sensitivity. One context in which IDPs play important roles that is concomitant with massive changes to the intracellular environment is during desiccation (extreme drying). The ability of organisms to survive desiccation has long been linked to the accumulation of high levels of cosolutes such as trehalose or sucrose as well as the enrichment of IDPs, such as late embryogenesis abundant (LEA) proteins or cytoplasmic abundant heat soluble (CAHS) proteins. Despite knowing that IDPs play important roles and are co-enriched alongside endogenous, species-specific cosolutes during desiccation, little is known mechanistically about how IDP-cosolute interactions influence desiccation tolerance. Here, we test the notion that the protective function of desiccation-related IDPs is enhanced through conformational changes induced by endogenous cosolutes. We find that desiccation-related IDPs derived from four different organisms spanning two LEA protein families and the CAHS protein family, synergize best with endogenous cosolutes during drying to promote desiccation protection. Yet the structural parameters of protective IDPs do not correlate with synergy for either CAHS or LEA proteins. We further demonstrate that for CAHS, but not LEA proteins, synergy is related to self-assembly and the formation of a gel. Our results suggest that functional synergy between IDPs and endogenous cosolutes is a convergent desiccation protection strategy seen among different IDP families and organisms, yet, the mechanisms underlying this synergy differ between IDP families.

Break Up with Salt (BUWS) is a four-session community-based nutrition education program aimed at reducing key controllable hypertension risk factors. This pilot study utilized a pre-post survey design to assess short-term outcomes on food behaviors (including DASH diet eating patterns), physical activity, and overall well-being, in two groups of participants. The first "pilot" group (n = 25) completed a comprehensive, 16-item survey; the second "abbreviated" group (n = 27) completed a 5-item survey. The pilot group experienced improvements in whole grain ( p = 0.04), sweetened beverage consumption, watching/reducing sodium ( p = 0.04) and fat ( p = 0.05) consumption, and time spent sitting ( p = 0.04). The abbreviated group improved confidence in using food labels ( p = 0.02), following the DASH diet ( p < 0.01), preparing food without salt ( p = 0.03), selecting lower sodium items when eating out ( p = 0.04), and making a positive lifestyle change ( p = 0.01). The BUWS program provides information and teaches strategies to manage or prevent hypertension. By effectively improving diet and food behaviors, BUWS has the potential to reduce hypertension risk factors and improve the general health of participants.

To survive extreme drying (anhydrobiosis), many organisms, spanning every kingdom of life, accumulate intrinsically disordered proteins (IDPs). For decades, the ability of anhydrobiosis-related IDPs to form transient amphipathic helices has been suggested to be important for promoting desiccation tolerance. However, evidence empirically supporting the necessity and/or sufficiency of helicity in mediating anhydrobiosis is lacking. Here, we demonstrate that the linker region of CAHS D, a desiccation-related IDP from the tardigrade Hypsibius exemplaris, that contains significant helical structure, is the protective portion of this protein. Perturbing the sequence composition and grammar of the linker region of CAHS D, through the insertion of helix-breaking prolines, modulating the identity of charged residues, or replacement of hydrophobic amino acids with serine or glycine residues results in variants with different degrees of helical structure. Importantly, correlation of protective capacity and helical content in variants generated through different helix perturbing modalities does not show as strong a trend, suggesting that while helicity is important, it is not the only property that makes a protein protective during desiccation. These results provide direct evidence for the decades-old theory that helicity of desiccation-related IDPs is linked to their anhydrobiotic capacity., (© 2023 The Protein Society.)

The home food environment (HFE), the availability and accessibility of foods and food products within the home, has a strong influence on healthy eating behaviors. Studies assessing the HFE commonly utilize a home food inventory (HFI) for data collection. However, this approach tends to be burdensome for participants. This study validated a low-burden digital photo method for assessing the home food environment and confirmed that this method is preferred by participants. Study participants completed an HFI, submitted photos of household foods, then identified preference for the HFI or photo reporting method. Researchers completed an HFI based on each participant's photo submissions. Researcher-to-participant and researcher-to-researcher comparisons were made through ANOVA and randomized block analyses to determine concurrent validity and inter-rater reliability. Method preference was assessed using the Z-test. The participant group (N = 53) was predominantly female (68%), young adult (90.5%), and Hispanic or Latino (71.7%). Concurrent validity was initially moderate (ĸ = 0.54); adjustments yielded substantial agreement (ĸ = 0.61). The inter-rater reliability ( p = 0.98) demonstrated significant consistency among reviewers. The photo-documentation method was found to be valid and preferred ( p = 0.01) for reporting on the HFE. The photo method can be used advantageously to collect quality data.

Snacks are a staple of the American diet, contributing to approximately 20% of energy intake. Most U.S. adults consume one to three snacks/day, yet few reviews have focused on snacking among this population. This scoping review was conducted to characterize snacks and snacking occasions among U.S. adults to further inform healthy eating practices. The protocol was prepared following the PRISMA-Extension for Scoping Reviews. Three web databases were used to identify articles using snacking or eating occasions as primary or secondary outcomes among U.S. adults. A search strategy was developed using subject headings, truncation, and phrase searching in the title and abstract of articles published between 2010 and 2022. A two-stage, multi-step screening process identified 31 of 4795 publications as meeting the inclusion criteria. Findings included identification of snacking themes, e.g., cues and motivations; diet composition; and weight management. Food quality, time of consumption, and convenience emerged as characteristics of snacking; time of day was found to influence food choice. Snacks contribute to or detract from a healthy diet. Strategic selection of healthy snack options can improve diet quality. Applied to nutrition education, this information can help strengthen programs or policies, ultimately contributing to health and wellbeing.

The community-based Small Changes, Healthy Habits (SCHH) program was developed to teach skills and techniques to help adults in Louisiana make and maintain small behavioral changes in their food selection, preparation, and consumption, and in physical activity routines. The content of this four-week program included habit formation and goal setting techniques; physical activity guidance; strategies for a healthier home food environment; a grocery store tour focused on label reading for healthier food selections; basic knife and cooking skills. The program was piloted at ten sites throughout the state. A survey with 14 core items was applied before and after the program to evaluate participant acquisition of skills and behaviors associated with topic areas. A total of 47 participants provided complete data sets. Post-program, these participants reported increased confidence in preparing healthy meals at home ( p = 0.04); changes in fats ( p = 0.03) and salt ( p = 0.01) intake; increased frequency of reading nutrition labels (32%); decreased frequency of meals eaten outside the home (Improvement Index = 0.27); and decreased time/day spent sitting ( p < 0.05). These short-term results suggest that the SCHH program has potential to positively affect healthy eating and to reduce sedentary behaviors, both of which are fundamental to good health and wellness.