Arabidopsis VILLIN5 bundles actin filaments using a novel mechanism.

Being a bona fide actin bundler, Arabidopsis villin5 (VLN5) plays a crucial role in regulating actin stability and organization within pollen tubes. Despite its significance, the precise mechanism through which VLN5 bundles actin filaments has remained elusive. Through meticulous deletion analysis, we have unveiled that the link between gelsolin repeat 6 (G6) and the headpiece domain (VHP), rather than VHP itself, is indispensable for VLN5-mediated actin bundling. Further refinement of this region has pinpointed a critical sequence spanning from Val763 to Ser823, essential for VLN5's actin-bundling activity. Notably, the absence of Val763-Ser823 in VLN5 results in decreased filamentous decoration within pollen tubes and a diminished ability to rescue actin bundling defects in vln2vln5 mutant pollen tubes compared to intact VLN5. Moreover, our findings highlight that the Val763-Ser823 sequence harbors a binding site for F-actin, suggesting that this linker-based F-actin binding site, in conjunction with the F-actin binding site localized in G1-G6, enables a single VLN5 to concurrently bind to two adjacent actin filaments. Therefore, our study unveils a novel mechanism by which VLN5 bundles actin filaments.

A role for endoplasmic reticulum dynamics in the cellular distribution of microtubules.

The dynamic distribution of the microtubule (MT) cytoskeleton is crucial for the shape, motility, and internal organization of eukaryotic cells. However, the basic principles that control the subcellular position of MTs in mammalian interphase cells remain largely unknown. Here we show by a combination of microscopy and computational modeling that the dynamics of the endoplasmic reticulum (ER) plays an important role in distributing MTs in the cell. Specifically, our physics-based model of the ER­MT system reveals that spatial inhomogeneity in the density of ER tubule junctions results in an overall contractile force that acts on MTs and influences their distribution. At steady state, cells rapidly compensate for local variability of ER junction density by dynamic formation, release, and movement of ER junctions across the ER. Perturbation of ER junction tethering and fusion by depleting the ER fusogens called atlastins disrupts the dynamics of junction equilibration, rendering the ER­MT system unstable and causing the formation of MT bundles. Our study points to a mechanical role of ER dynamics in cellular organization and suggests a mechanism by which cells might dynamically regulate MT distribution in, e.g., motile cells or in the formation and maintenance of neuronal axons.

StMLP1, as a Kunitz trypsin inhibitor, enhances potato resistance and specifically expresses in vascular bundles during Ralstonia solanacearum infection.

Miraculin-like proteins (MLPs), members of the Kunitz trypsin inhibitor (KTI) family that are present in various plants, have been discovered to have a role in defending plants against pathogens. In this study, we identified a gene StMLP1 in potato that belongs to the KTI family. We found that the expression of StMLP1 gradually increases during Ralstonia solanacearum (R. solanacearum) infection. We characterized the promoter of StMLP1 as an inducible promoter that can be triggered by R. solanacearum and as a tissue-specific promoter with specificity for vascular bundle expression. Our findings demonstrate that StMLP1 exhibits trypsin inhibitor activity, and that its signal peptide is essential for proper localization and function. Overexpression of StMLP1 in potato can enhance the resistance to R. solanacearum. Inhibiting the expression of StMLP1 during infection accelerated the infection by R. solanacearum to a certain extent. In addition, the RNA-seq results of the overexpression-StMLP1 lines indicated that StMLP1 was involved in potato immunity. All these findings in our study reveal that StMLP1 functions as a positive regulator that is induced and specifically expressed in vascular bundles in response to R. solanacearum infection.

Code ICH: A Call to Action.

Intracerebral hemorrhage is the most serious type of stroke, leading to high rates of severe disability and mortality. Hematoma expansion is an independent predictor of poor functional outcome and is a compelling target for intervention. For decades, randomized trials aimed at decreasing hematoma expansion through single interventions have failed to meet their primary outcomes of statistically significant improvement in neurological outcomes. A wide range of evidence suggests that ultra-early bundled care, with multiple simultaneous interventions in the acute phase, offers the best hope of limiting hematoma expansion and improving functional recovery. Patients with intracerebral hemorrhage who fail to receive early aggressive care have worse outcomes, suggesting that an important treatment opportunity exists. This consensus statement puts forth a call to action to establish a protocol for Code ICH, similar to current strategies used for the management of acute ischemic stroke, through which early intervention, bundled care, and time-based metrics have substantially improved neurological outcomes. Based on current evidence, we advocate for the widespread adoption of an early bundle of care for patients with intracerebral hemorrhage focused on time-based metrics for blood pressure control and emergency reversal of anticoagulation, with the goal of optimizing the benefit of these already widely used interventions. We hope Code ICH will endure as a structural platform for continued innovation, standardization of best practices, and ongoing quality improvement for years to come.

Medullary bundles in Caryophyllales: form, function, and evolution.

The occurrence of conducting vascular tissue in the pith (CVTP) of tracheophytes is noteworthy. Medullary bundles, one of the remarkable examples of CVTP, evolved multiple times across angiosperms, notably in the Caryophyllales. Yet, information on the occurrence of medullary bundles is fragmented, hampering our understanding of their structure-function relationships, and evolutionary implications. Using three plastid molecular markers (matK, rbcL, and rps16 intron), a phylogeny is constructed for 561 species of Caryophyllales, and anatomical data are assembled for 856 species across 40 families to investigate the diversity of medullary bundles, their function, evolution, and diversification dynamics. Additionally, correlated evolution between medullary bundles and successive cambia was tested. Medullary bundles are ancestrally absent in Caryophyllales and evolved in core and noncore families. They are structurally diverse (e.g. number, arrangement, and types of bundles) and functionally active throughout the plant's lifespan, providing increased hydraulic conductivity, especially in herbaceous plants. Acquisition of medullary bundles does not explain diversification rate heterogeneity but is correlated to a higher diversification rate. Disparate developmental pathways were found leading to rampant convergent evolution of CVTP in Caryophyllales. These findings indicate the diversification of medullary bundles and vascular tissues as another central theme for functional and comparative molecular studies in Caryophyllales.

Architectonic principles of polyproline II helix bundle protein domains.

Glycine rich polyproline II helix assemblies are an emerging class of natural domains found in several proteins with different functions and diverse origins. The distinct properties of these domains relative to those composed of α-helices and ß-sheets could make glycine-rich polyproline II helix assemblies a useful building block for protein design. Whereas the high population of polyproline II conformers in disordered state ensembles could facilitate glycine-rich polyproline II helix folding, the architectonic bases of these structures are not well known. Here, we compare and analyze their structures to uncover common features. These protein domains are found to be highly tolerant of distinct flanking sequences. This speaks to the robustness of this fold and strongly suggests that glycine rich polyproline II assemblies could be grafted with other protein domains to engineer new structures and functions. These domains are also well packed with few or no cavities. Moreover, a significant trend towards antiparallel helix configuration is observed in all these domains and could provide stabilizing interactions among macrodipoles. Finally, extensive networks of Cα-H···OC hydrogen bonds are detected in these domains. Despite their diverse evolutionary origins and activities, glycine-rich polyproline II helix assemblies share architectonic features which could help design novel proteins.

Rap1 small GTPase is essential for maintaining pulmonary endothelial barrier function in mice.

Vascular permeability is dynamically but tightly controlled by vascular endothelial (VE)-cadherin-mediated endothelial cell-cell junctions to maintain homeostasis. Thus, impairments of VE-cadherin-mediated cell adhesions lead to hyperpermeability, promoting the development and progression of various disease processes. Notably, the lungs are a highly vulnerable organ wherein pulmonary inflammation and infection result in vascular leakage. Herein, we showed that Rap1, a small GTPase, plays an essential role for maintaining pulmonary endothelial barrier function in mice. Endothelial cell-specific Rap1a/Rap1b double knockout mice exhibited severe pulmonary edema. They also showed vascular leakage in the hearts, but not in the brains. En face analyses of the pulmonary arteries and 3D-immunofluorescence analyses of the lungs revealed that Rap1 potentiates VE-cadherin-mediated endothelial cell-cell junctions through dynamic actin cytoskeleton reorganization. Rap1 inhibits formation of cytoplasmic actin bundles perpendicularly binding VE-cadherin adhesions through inhibition of a Rho-ROCK pathway-induced activation of cytoplasmic nonmuscle myosin II (NM-II). Simultaneously, Rap1 induces junctional NM-II activation to create circumferential actin bundles, which anchor and stabilize VE-cadherin at cell-cell junctions. We also showed that the mice carrying only one allele of either Rap1a or Rap1b out of the two Rap1 genes are more vulnerable to lipopolysaccharide (LPS)-induced pulmonary vascular leakage than wild-type mice, while activation of Rap1 by administration of 007, an activator for Epac, attenuates LPS-induced increase in pulmonary endothelial permeability in wild-type mice. Thus, we demonstrate that Rap1 plays an essential role for maintaining pulmonary endothelial barrier functions under physiological conditions and provides protection against inflammation-induced pulmonary vascular leakage.

Menaquinone-4 Alleviates Neurological Deficits Associated with Intracerebral Hemorrhage by Preserving Corticospinal Tract in Mice.

Menaquinone-4 (MK-4) is an isoform of vitamin K2 that has been shown to exert various biological actions besides its functions in blood coagulation and bone metabolism. Here we examined the effect of MK-4 on a mouse model of intracerebral hemorrhage (ICH). Daily oral administration of 200 mg/kg MK-4 starting from 3 h after induction of ICH by intrastriatal collagenase injection significantly ameliorated neurological deficits. Unexpectedly, MK-4 produced no significant effects on various histopathological parameters, including the decrease of remaining neurons and the increase of infiltrating neutrophils within the hematoma, the increased accumulation of activated microglia/macrophages and astrocytes around the hematoma, as well as the injury volume and brain swelling by hematoma formation. In addition, ICH-induced increases in nitrosative/oxidative stress reflected by changes in the immunoreactivities against nitrotyrosine and heme oxygenase-1 as well as the contents of malondialdehyde and glutathione were not significantly affected by MK-4. In contrast, MK-4 alleviated axon tract injury in the internal capsule as revealed by neurofilament-H immunofluorescence. Enhanced preservation of the corticospinal tract by MK-4 was also confirmed by retrograde labeling of neurons in the primary motor cortex innervating the spinal cord. These results suggest that MK-4 produces therapeutic effect on ICH by protecting structural integrity of the corticospinal tract.

Implementation of a surgical site infection prevention bundle in gynecologic oncology patients: An enhanced recovery after surgery initiative.

OBJECTIVE: To evaluate the clinical outcomes pre- and post-implementation of an evidence-informed surgical site infection prevention bundle (SSIPB) in gynecologic oncology patients within an Enhanced Recovery After Surgery (ERAS) care pathway. METHODS: Patients undergoing laparotomy for a gynecologic oncology surgery between January-June 2017 (pre-SSIPB) and between January 2018-December 2020 (post-SSIPB) were compared using t-tests and chi-square. Patient characteristics, surgical factors, and ERAS process measures and outcomes were abstracted from the ERAS® Interactive Audit System (EIAS). The primary outcomes were incidence of surgical site infections (SSI) during post-operative hospital admission and at 30-days post-surgery. Secondary outcomes included total postoperative infections, length of stay, and any surgical complications. Multivariate models were used to adjust for potential confounding factors. RESULTS: Patient and surgical characteristics were similar in the pre- and post-implementation periods. Evaluation of implementation suggested that preoperative and intraoperative components of the intervention were most consistently used. Infectious complications within 30 days of surgery decreased from 42.1% to 24.4% after implementation of the SSIPB (p < 0.001), including reductions in wound infections (17.0% to 10.8%, p = 0.02), urinary tract infections (UTI) (12.7% to 4.5%, p < 0.001), and intra-abdominal abscesses (5.4% to 2.5%, p = 0.05). These reductions were associated with a decrease in median length of stay from 3 to 2 days (p = 0.001). In multivariate analysis, these SSI reductions remained statistically significant after adjustment for potential confounders. CONCLUSION: Implementation of SSIPB was associated with a reduction in SSIs and infectious complications, as well as a shorter length of stay in gynecologic oncology patients.

Effectiveness of care bundles for prevention and treatment of postpartum hemorrhage: a systematic review.

OBJECTIVE: Care bundles are a promising approach to reducing postpartum hemorrhage-related morbidity and mortality. We assessed the effectiveness and safety of care bundles for postpartum hemorrhage prevention and/or treatment. DATA SOURCES: We searched MEDLINE, Embase, Cochrane CENTRAL, Maternity and Infant Care Database, and Global Index Medicus (inception to June 9, 2023) and ClinicalTrials.gov and the International Clinical Trials Registry Platform (last 5 years) using a phased search strategy, combining terms for postpartum hemorrhage and care bundles. STUDY ELIGIBILITY CRITERIA: Peer-reviewed studies evaluating postpartum hemorrhage-related care bundles were included. Care bundles were defined as interventions comprising ≥3 components implemented collectively, concurrently, or in rapid succession. Randomized and nonrandomized controlled trials, interrupted time series, and before-after studies (controlled or uncontrolled) were eligible. METHODS: Risk of bias was assessed using RoB 2 (randomized trials) and ROBINS-I (nonrandomized studies). For controlled studies, we reported risk ratios for dichotomous outcomes and mean differences for continuous outcomes, with certainty of evidence determined using GRADE. For uncontrolled studies, we used effect direction tables and summarized results narratively. RESULTS: Twenty-two studies were included for analysis. For prevention-only bundles (2 studies), low-certainty evidence suggests possible benefits in reducing blood loss, duration of hospitalization, and intensive care unit stay, and maternal well-being. For treatment-only bundles (9 studies), high-certainty evidence shows that the E-MOTIVE intervention reduced risks of composite severe morbidity (risk ratio, 0.40; 95% confidence interval, 0.32-0.50) and blood transfusion for bleeding, postpartum hemorrhage, severe postpartum hemorrhage, and mean blood loss. One nonrandomized trial and 7 uncontrolled studies suggest that other postpartum hemorrhage treatment bundles might reduce blood loss and severe postpartum hemorrhage, but this is uncertain. For combined prevention/treatment bundles (11 studies), low-certainty evidence shows that the California Maternal Quality Care Collaborative care bundle may reduce severe maternal morbidity (risk ratio, 0.64; 95% confidence interval, 0.57-0.72). Ten uncontrolled studies variably showed possible benefits, no effects, or harms for other bundle types. Nearly all uncontrolled studies did not use suitable statistical methods for single-group pretest-posttest comparisons and should thus be interpreted with caution. CONCLUSION: The E-MOTIVE intervention improves postpartum hemorrhage-related outcomes among women delivering vaginally, and the California Maternal Quality Care Collaborative bundle may reduce severe maternal morbidity. Other bundle designs warrant further effectiveness research before implementation is contemplated.

Anatomical and physiological responses of roots and rhizomes in Oryza longistaminata to soil water gradients.

BACKGROUND AND AIMS: Roots and rhizomes are critical for the adaptation of clonal plants to soil water gradients. Oryza longistaminata, a rhizomatous wild rice, is of particular interest for perennial rice breeding due to its resilience under abiotic stress conditions. While root responses to soil flooding are well-studied, rhizome responses to water gradients remain underexplored. We hypothesize that physiological integration of Oryza longistaminata mitigates heterogeneous water deficit stress through interconnected rhizomes, and both roots and rhizomes respond to contrasting water conditions. METHODS: We investigated the physiological integration between mother plants and ramets, measuring key photosynthetic parameters (photosynthetic and transpiration rate, and stomatal conductance) using an Infrared Gas Analyzer. Moreover, root and rhizome responses to three water regimes (flooding, well-watered, and water deficit) were examined by measuring radial water loss and apparent permeance to O2, along with histochemical and anatomical characterization. KEY RESULTS: Our experiment highlights the role of physiological integration via interconnected rhizomes in mitigating water deficit stress. Severing rhizome connections from mother plants or ramets exposed to water deficit conditions led to significant decreases in key photosynthetic parameters, underscoring the importance of rhizome connections in bidirectional stress mitigation. Additionally, O. longistaminata rhizomes exhibited constitutive suberized and lignified apoplastic barriers, while such barriers were induced in roots under water stress. Anatomically, both rhizomes and roots respond similarly to water gradients, showing thinner diameters under water deficit conditions and larger diameters under flooding conditions. CONCLUSION: Our findings indicate that physiological integration through interconnected rhizomes helps alleviate water deficit stress when either the mother plant or the ramet is experiencing water deficit, while the counterpart is in control conditions. Moreover, O. longistaminata can adapt to various soil water regimes by regulating anatomical and physiological traits of roots and rhizomes.

Blood Pressure Management in Intracerebral Haemorrhage: when, how much, and for how long?

PURPOSE OF REVIEW: When compared to ischaemic stroke, there have been limited advances in acute management of intracerebral haemorrhage. Blood pressure control in the acute period is an intervention commonly implemented and recommended in guidelines, as elevated systolic blood pressure is common and associated with haematoma expansion, poor functional outcomes, and mortality. This review addresses the uncertainty around the optimal blood pressure intervention, specifically timing and length of intervention, intensity of blood pressure reduction and agent used. RECENT FINDINGS: Recent pivotal trials have shown that acute blood pressure intervention, to a systolic target of 140mmHg, does appear to be beneficial in ICH, particularly when bundled with other therapies such as neurosurgery in selected cases, access to critical care units, blood glucose control, temperature management and reversal of coagulopathy. Systolic blood pressure should be lowered acutely in intracerebral haemorrhage to a target of approximately 140mmHg, and that this intervention is generally safe in the ICH population.

Exploring watershed ecological risk bundles based on ecosystem services: A case study of Shanxi Province, China.

Humans are having an increasingly profound impact on the environment along with the advent of the Anthropocene. Ecological risk assessment (ERA) as a method to quantify ecological problems can provide support for decision-makers, and it is one of key issues to integrate ecosystem services into ERA. In this study, an ERA framework was proposed under the loss-probability paradigm from the perspective of ecosystem services risk bundles. The results showed that initiatives aimed at ecological protection in Shanxi Province had been effective, the number of watersheds with low-risk bundles increased significantly (from 16.09% to 34.49%) and the watersheds basically overlapped with key forestation areas. However, the effects of forestation activities may no longer be as significant as they once were, as the relationship between forestation and water supply was becoming increasingly contradictory. Meanwhile, the conflict between urban expansion and natural ecosystem protection was intensifying, habitat degradation risks were gradually polarized, and the risk bundles dominated by high carbon emission and habitat degradation were increasing significantly (from 15.88% to 33.54%). Strengthening the construction of urban green space and controlling the expansion of human activities may be the next focus of ecological conservation in Shanxi Province. This study enriched the ERA framework with an ecosystem services risk bundle approach.

Phloem and Xylem Responses Are Both Implicated in Huanglongbing Tolerance of Sugar Belle.

Although huanglongbing (HLB) is a devastating citrus disease, improved tolerant cultivars, such as Sugar Belle (SB) mandarin, have been identified. To understand the responses that HLB-affected SB undergoes, we compared 14CO2 fixation, carbohydrate export, phloem callose accumulation, relative expression of plant defense activators, and anatomical changes between healthy and infected SB trees versus susceptible Pineapple (PA) sweet orange. Eight- to ten-week-old leaves of infected SB showed a 2.5-fold increase in 14CO2 fixation and a 13% decrease in 14C-carbohydrate export, whereas HLB-affected PA presented a decrease of 33 and 50%, respectively. The mean distance of a callose deposit to its closest neighbor was 36% smaller in infected SB versus healthy, whereas in HLB-affected PA, it was 33% higher. Expression of papain-like cysteine proteases (PLCPs) was upregulated in SB but downregulated in PA. Infected SB showed minor alterations in the number of xylem vessels, a 16% larger xylem vessel lumen area, and a 14% increase in the proportional area of the xylem. In contrast, PA showed a 2.4-fold increase in the xylem vessel number and a 2% increase in the proportional xylem area. Three complementary mechanisms of tolerance in SB are hypothesized: (i) increased carbohydrate availability induced by greater CO2 fixation, mild effect in carbohydrate export, and local accumulation of callose in the phloem; (ii) activation of defense response via upregulation of PLCPs, and (iii) increased investment in the xylem structure. Thus, phloem and xylem modifications seem to be involved in SB tolerance.

Skilled Nursing and Home Health Policy: A Primer for the Hospital Clinician.

This paper addresses the increasing challenges faced by hospital clinicians in coordinating and recommending postacute care for patients, focusing on issues related to access to the most common postacute services: skilled nursing facilities (SNFs) and home health agencies (HHAs). In coordinating discharges, hospital clinicians have minimal information on care delivery in these settings. This knowledge gap is exacerbated by the disrupted continuum of patient care between acute care hospitals, SNFs, and HHAs. To address these challenges, hospital clinicians must understand how recent federal policies have impacted SNF and HHA care provision. The paper provides an overview of recent Centers for Medicare and Medicaid Services (CMS) policies and programs affecting SNFs and HHAs, including: (1) fee-for-service reimbursement reform (ie, Patient Driven Payment Model [PDPM] and the Patient Driven Groupings Model [PDGM]); (2) bundled payment programs; (3) accountable care organizations; (4) Medicare Advantage plans. Overall, this paper aims to help hospital clinicians stay informed about the evolving landscape of postacute care delivery by providing relevant information on how recent policy changes have impacted patient care.

Pelvic Neuro-Visualization: An Anatomical Illustration of the Autonomic Pelvic Nervous Network in Gynecologic Surgery.

OBJECTIVE: During radical pelvic surgeries fibers of the autonomic pelvic nervous network can be accidentally damaged leading to significant visceral sequelae, which dramatically affect women's quality of life because of urinary, anorectal, and sexual postoperative dysfunctions.1,2 Direct visualization is one way to preserve hypogastric nerves (HNs), pelvic splanchnic nerves (PSNs), and the bladder branches from the inferior hypogastric plexus (IHP). However, the literature lacks critical photos and/or illustrations that are necessary to understand the precise anatomy needed to preserve the pelvic autonomic fibers. DESIGN: Narrated laparoscopic video footage for identifying, dissecting, and preserving the autonomic nerve bundles during pelvic surgery. SETTING: Tertiary level hospital-"IRCCS Istituto Nazionale dei Tumori", Milano, Italy. INTERVENTIONS: Visceral pelvic innervation is established by the superior hypogastric plexus(SHP) located anteriorly to the aortic bifurcation and the median sacral vessels and carries mostly sympathetic fibers. SHP divides in front of the sacrum into the right and left HN. At the level of the paracervix, the HNs join the parasympathetic PSNs coming out from sacral root S2, S3, S4 to form the IHP.2-5 Here, we performed laparoscopic surgery, before "Laparoscopic Approach to Cervical Cancer" trial (LACC) era, identifying key anatomic landmarks useful to highlight the path of the most commonly encountered autonomic pelvic nerves in gynecologic radical surgery: during the narration we describe and illustrate the procedure to identify all autonomic pelvic nerves, the sympathetic fibers, the PSNs, and the bladder branch emerging from the IHP in order to preserve their anatomic and functional integrity. This technique is anatomically and surgically indicated for adequate removal of the parametrical issues and vagina while preserving the total pelvic nervous system. CONCLUSION: Nerve-sparing surgery reduces bowel-, bladder- and sexual- dysfunction without decreasing surgical efficacy.1,2 To accomplish safe and effective surgery, comprehension of the 3 dimensional structure of the vascular and nerve anatomy in the pelvis is essential. This video provides a great resource to educate surgeons, especially the youngest ones, about the retroperitoneal nervous networking: we identified the autonomic nerve pathway from adjacent tissues along the pathway consisting of cardinal, sacro-uterine, rectouterine/vaginal, and vesico-uterine ligaments.

Evaluation of ventilator-associated pneumonia care practice in the intensive care units of a comprehensive specialized hospital in Northwest Ethiopia: a 1.5-year prospective observational study.

BACKGROUND: Nosocomial infections pose a global health threat, with Ventilator-Associated Pneumonia (VAP) emerging as a prominent hospital-acquired infection, particularly in intensive care units (ICU).VAP is the commonest form of pneumonia in ICUs, contributing significantly to morbidity and mortality rates, which can reach around 30%. Despite the substantial impact of VAP on healthcare, there is a lack of data on adherence to VAP prevention protocols in our hospital. Consequently, this study aims to assess the adherence to ventilator-associated pneumonia care bundles in critical care units at a comprehensive specialized hospital in northwest Ethiopia. METHODS: A hospital-based prospective observational study was conducted from July 3, 2022, to January 7, 2024. All adult patients who were on mechanical ventilators for more than 48 h during the study period were included. Data were collected using the Institute of Healthcare Improvement VAP prevention standards as checklists via direct observation and chart review. The data were entered and analyzed using SPSS version 20. RESULTS: A total of 300 surgical and medical ICU patients were observed. Among the patients, 66.3% were from the medical ICU. In terms of admission reasons, 22.3%, 15.7% and, 12% were attributed to infections excluding respiratory origin, respiratory disorders, and other causes, respectively. The rate of compliance with all components of the bundle was 70%. A 100% adherence rate was observed for the prophylaxis for peptic ulcer and deep vein thrombosis (DVT). The lowest adherence rate was observed in the practice of oral hygiene with 0.5% chlorhexidine solution (0%) followed by humidification with heat and moisture exchangers (23.3%). Endotracheal tube cuff pressure measurement and use of endotracheal tubes with subglottic suction were not applicable. CONCLUSION: The study revealed suboptimal compliance with the VAP care bundle, indicating unsatisfactory overall practice. Specific attention is warranted for subglottic suction, cuff pressure measurement, humidification, oral care with chlorhexidine, and sedation vacation.

Topological defects produce kinks in biopolymer filament bundles.

Bundles of stiff filaments are ubiquitous in the living world, found both in the cytoskeleton and in the extracellular medium. These bundles are typically held together by smaller cross-linking molecules. We demonstrate, analytically, numerically, and experimentally, that such bundles can be kinked, that is, have localized regions of high curvature that are long-lived metastable states. We propose three possible mechanisms of kink stabilization: a difference in trapped length of the filament segments between two cross-links, a dislocation where the endpoint of a filament occurs within the bundle, and the braiding of the filaments in the bundle. At a high concentration of cross-links, the last two effects lead to the topologically protected kinked states. Finally, we explore, numerically and analytically, the transition of the metastable kinked state to the stable straight bundle.

Extreme mechanical anisotropy in diamond with preferentially oriented nanotwin bundles.

Mechanical properties of covalent materials can be greatly enhanced with strategy of nanostructuring. For example, the nanotwinned diamond with an isotropic microstructure of interweaved nanotwins and interlocked nanograins shows unprecedented isotropic mechanical properties. How the anisotropic microstructure would impact on the mechanical properties of diamond has not been fully investigated. Here, we report the synthesis of diamond from superaligned multiwalled carbon nanotube films under high pressure and high temperature. Structural characterization reveals preferentially oriented diamond nanotwin bundles with an average twin thickness of ca. 2.9 nm, inherited from the directional nanotubes. This diamond exhibits extreme mechanical anisotropy correlated with its microstructure (e.g., the average Knoop hardness values measured with the major axis of the indenter perpendicular and parallel to nanotwin bundles are 233 ± 8 and 129 ± 9 GPa, respectively). Molecular dynamics simulation reveals that, in the direction perpendicular to the nanotwin bundles, the dense twin boundaries significantly hinder the motion of dislocations under indentation, while such a resistance is much weaker in the direction along the nanotwin bundles. Current work verifies the hardening effect in diamond via nanostructuring. In addition, the mechanical properties can be further tuned (anisotropy) with microstructure design and modification.

The REPLUMLESS Transcription Factor Controls the Expression of the RECEPTOR-LIKE CYTOPLASMIC KINASE VI_A2 Gene Involved in Shoot and Fruit Patterning of Arabidopsis thaliana.

The promoter of the RECEPTOR-LIKE CYTOPLASMIC KINASE VI_A2 (RLCK VI_A2) gene contains nine binding sites for the REPLUMLESS (RPL) transcription factor. In agreement, the expression of the kinase gene was strongly downregulated in the rpl-4 mutant. Comparing phenotypes of loss-of-function mutants, it was revealed that both genes are involved in stem growth, phyllotaxis, organization of the vascular tissues, and the replum, highlighting potential functional interactions. The expression of the RLCKVI_A2 gene from the constitutive 35S promoter could not complement the rpl-4 phenotypes but exhibited a dominant positive effect on stem growth and affected vascular differentiation and organization. The results also indicated that the number of vascular bundles is regulated independently from stem thickness. Although our study cannot demonstrate a direct link between the RPL and RLVKVI_A2 genes, it highlights the significance of the proper developmental regulation of the RLCKVI_A2 promoter for balanced stem development.