Controlling Influence of Phosphocitrate In Vitro and In Vivo on Calcium Oxalate Crystal Formation and Growth

Calcium oxalate (CaOx) crystallization in the presence of phosphocitrate (PC) was studied by both in vitro and in vivo techniques. Crystals of the monohydrate (COM) and the dihydrate (COD) forms were generated under controlled conditions in a silica gel matrix. Our data indicated only COD crystals formed when PC was present, inferring that the COD to COM transformation was being impeded. COD crystals were smaller in size than controls and there was evidence of interpenetral twinning. An in vivo study using a rat bladder implant model noted similar findings. Scanning electron microscopy (SEM) revealed that implants recovered from PC treated rats had primarily COD crystals deposited, whereas both the surface and inner layers of encrusted implants from normal rats contained predominantly COM crystals. Infrared (IR) analysis confirmed the visual findings indicating quantitatively that there was a higher proportion of COD present on the implants recovered from the treated rats than in the controls. It is concluded that although total CaOx crystallization cannot be eliminated by PC, its action could assist in reducing the harmful nature of such crystallites in the urine

Enhancement of the Adhesive Properties by Optimizing the Water Content in PNIPAM-Functionalized Complex Coacervates

Most commercially available soft tissue glues offer poor performance in the human body. We have developed an injectable adhesive whose setting mechanism is activated by a change in environmental factors, i.e., temperature and/or ionic strength. The material and setting process are inspired by the adhesive processing mechanism observed in natural maritime glues. Complex coacervation, a liquid-liquid phase separation between oppositely charged polyelectrolytes, is thought to play an important role in the processing. Complex coacervates are characterized by a high water content, which inevitably weakens the glue. Here, we aim to increase the adhesive performance by systematically tuning the water content. Among the several strategies here explored, the most effective one is the mechanical removal of water using an extruder, resulting in an increase of work of adhesion by 1 order of magnitude compared to the original formulation

Imaging of Four Planetary Nebulae in the Magellanic Clouds Using the Hubble Space Telescope Faint Object Camera

Using the Faint Object Camera on-board the Hubble Space Telescope, we have obtained images of four planetary nebulae (PNe) in the Magellanic Clouds, namely N2 and N5 in the SMC and N66 and N201 in the LMC. Each nebula was imaged through two narrow-band filters isolating [O III] λ5007 and Hβ, for a nominal exposure time of 1000 s in each filter. Significant detail is evident on the raw images and, after deconvolution using the Richardson-Lucy algorithm, structures as small as 0.06" are easily discernible. In [O III], SMC N5 shows a circular ring structure, with a peak-to-peak diameter of 0.26" and a FWHM of 0.35", while SMC N2 shows an elliptical ring structure with a peak-to-peak diameter of 0.26" x 0.21" (FWHM 0.40" x 0.35"). The expansion ages corresponding to the observed structures in SMC N2 and N5 are of the order of 3000 yr. Such low ages appear more easy to reconcile with helium-burning rather than hydrogen-burning central star evolutionary tracks. LMC N201 is very compact, with a FWHM of 0.21" in Hβ. The Type I PN LMC N66 is a multipolar nebula, with the brightest part having an extent of about 2" and with fainter structures extending over 4". The [O III] image reveals structures unprecedented for a planetary nebula, with several bright knots and faint loops visible outside the two main bright lobes

Tethering Cells via Enzymatic Oxidative Crosslinking Enables Mechanotransduction in Non-Cell-Adhesive Materials

Cell–matrix interactions govern cell behavior and tissue function by facilitating transduction of biomechanical cues. Engineered tissues often incorporate these interactions by employing cell-adhesive materials. However, using constitutively active cell-adhesive materials impedes control over cell fate and elicits inflammatory responses upon implantation. Here, an alternative cell–material interaction strategy that provides mechanotransducive properties via discrete inducible on-cell crosslinking (DOCKING) of materials, including those that are inherently non-cell-adhesive, is introduced. Specifically, tyramine-functionalized materials are tethered to tyrosines that are naturally present in extracellular protein domains via enzyme-mediated oxidative crosslinking. Temporal control over the stiffness of on-cell tethered 3D microniches reveals that DOCKING uniquely enables lineage programming of stem cells by targeting adhesome-related mechanotransduction pathways acting independently of cell volume changes and spreading. In short, DOCKING represents a bioinspired and cytocompatible cell-tethering strategy that offers new routes to study and engineer cell–material interactions, thereby advancing applications ranging from drug delivery, to cell-based therapy, and cultured meat

Association between Childhood Body Size and Premenstrual Disorders in Young Adulthood

The work is supported by grant 2020-01003 from the Swedish Research Council (Vetenskapsrådet) (Dr Lu) and grant 2020-00971 from the Swedish Research Council for Health, Working Life, and Welfare (FORTE) (Dr Lu). The Growing Up Today Study is supported by grants R03 CA106238 and U01 HL145386 from the National Institutes of Health. Publisher Copyright: © 2022 American Medical Association. All rights reserved.Importance: Emerging data suggest that more than two-thirds of premenstrual disorders (PMDs), including premenstrual syndrome and premenstrual dysphoric disorder, have symptom onset during the teen years. Adulthood adiposity has been associated with PMDs; however, the association with childhood and adolescent body size is unknown. Objective: To examine the association between childhood and adolescent body size and risk of PMDs in young adulthood. Design, Setting, and Participants: This prospective cohort study included 6524 US female participants from the Growing Up Today Study (1996-2013). Data were analyzed from February 26, 2020, to June 23, 2021. Exposures: Body mass index (BMI) was estimated using self-reported height and weight through adolescence and converted to BMI for age (z score). Main Outcomes and Measures: In 2013, premenstrual symptoms and identified PMDs were assessed with a validated scale based on the Calendar of Premenstrual Experiences. The associations of BMI for age with PMDs and premenstrual symptoms were examined using log-binomial and linear regressions, respectively. Results: Among 6524 participants (mean [SD] age, 26 [3.5] years; 6108 [93.6%] White), 1004 (15.4%) met the criteria for a PMD. Baseline BMI for age reported at a mean (SD) age of 12.7 (1.1) years was associated with increased risk of PMDs (confounding-adjusted relative risk, 1.09 per unit of z score; 95% CI, 1.03-1.15) and higher burden of premenstrual symptoms (β = 0.06; 95% CI, 0.04-0.08). Associations were particularly pronounced for premenstrual dysphoric disorder and for PMDs with symptom onset before 20 years of age and remained in the absence of psychiatric comorbidities, including depression, anxiety, and disordered eating behavior. When analyzing BMI change over time, individuals with high BMI throughout adolescence had a higher burden of premenstrual symptoms (β = 0.17; 95% CI, 0.08-0.27) compared with those with normal BMI throughout adolescence. Individuals with high BMI early followed by a mild decrease later did not report higher premenstrual symptoms (β = 0.06; 95% CI, 0.00-0.12). Conclusions and Relevance: In this cohort study, childhood body size was associated with PMD risk and premenstrual symptoms in young adulthood. These findings suggest that maintaining a normal body mass in childhood may be considered for lowering the burden of PMDs in adulthood..Peer reviewe

Optimal adhesion control via cooperative hierarchy, grading, geometries and non-linearity of anchorages

Optimization of dry adhesion in biological organisms is achieved using various strategies at different scale levels. In the past, studies have shown how contact splitting is used effectively by animals such as geckos and insects to increase the total peeling line of contacts and therefore the adhesion force. Also, tapering of contacts or grading of their mechanical properties has been shown to be instrumental in the achievement of improved adhesion efficiency. On a more macroscopic scale, structures such as spider web anchorages exploit hierarchical structure or nonlinear constitutive material properties to improve resilience and to achieve tunability in adhesion/detachment characteristics. Here, we analyse some of these properties and propose some mechanisms for the optimization of adhesion that have thus far been neglected in modelling approaches, and could be potentially exploited for the design of bioinspired adhesives. We consider hierarchical structure, contact tapering, grading of mechanical properties, and their interaction. It emerges that these mechanisms contribute on various size scales to the achievement of optimal adhesive properties through structural complexity and hierarchical organization

The effect on mental health of a large scale psychosocial intervention for survivors of mass violence: A quasi-experimental study in Rwanda

Background: War has serious and prolonged mental health consequences. It is argued that post-emergency mental health interventions should not only focus on psychological factors but also address the social environment. No controlled trials of such interventions exist. We studied the effect on mental health of a large scale p