Evolution of the basic Helix-Loop-Helix transcription factor SPATULA and its role in gynoecium development.

BACKGROUND AND AIMS: SPATULA (SPT) encodes a basic Helix-Loop-Helix transcription factor in Arabidopsis thaliana that functions in the development of the style, stigma and replum tissues, all of which arise from the carpel margin meristem (CMM) of the gynoecium. Here, we use a comparative approach to investigate the evolutionary history of SPT and identify changes that potentially contributed to its role in gynoecium development. METHODS: We investigate SPT's molecular and functional evolution using phylogenetic reconstruction, yeast-2-hybrid analyses of protein-protein interactions, microarray-based analyses of protein-DNA interactions, plant transformation assays, RNA in-situ hybridization, and in-silico analyses of promoter sequences. KEY RESULTS: We demonstrate the SPT lineage to have arisen at the base of euphyllophytes from a clade of potentially light-regulated transcription factors through gene duplication followed by the loss of an Active Phytochrome Binding (APB) domain. We also clarify the more recent evolutionary history of SPT and its paralog ALCATRAZ (ALC), which appear to have arisen through a large-scale duplication within Brassicales. We find that SPT orthologs from diverse groups of seed plants share strikingly similar capacities for protein-protein and protein-DNA interactions, and that SPT coding regions from a wide taxonomic range of plants are able to complement loss-of-function spt mutations in transgenic Arabidopsis. However, the expression pattern of SPT appears to have evolved significantly within angiosperms, and we identify structural changes in SPT's promoter region that correlate with the acquisition of high expression levels in tissues arising from the CMM in Brassicaeae. CONCLUSIONS: We conclude that changes to SPT's expression pattern made a major contribution to the evolution of its developmental role in the gynoecium of Brassicaeae. By contrast, the main biochemical capacities of SPT, as well as many of its immediate transcriptional targets, appear to have been conserved at least since the base of living angiosperms.

Interaction of a non-axisymmetric artificial single spatula with rough surfaces.

Hair-like attachment structures are frequently used by animals to create stable contact with rough surfaces. Previous studies focused primarily on axisymmetric biomimetic models of artificial spatulas, such as those with a mushroom-shaped and cylinder-shaped geometry, in order to simulate the so-called gecko effect. Here, two geometric prototypes of artificial adhesive structures with non-axisymmetric properties were designed. The investigation of the prototype's interactions with rough surfaces was carried out using the finite element software ABAQUS. Under increasing vertical displacement, the effect of asperity size on the contact pressure evolution of the spatula was investigated. It has been demonstrated that the contact behaviour is greatly affected by the flexibility of the spatula, which is caused by its variable thickness. The thinner spatula shows a higher nominal contact area and attaches more strongly to various rough surfaces. Although a thicker spatula is more susceptible to the 'leverage' phenomenon, which occurs when excessively applied displacements prematurely reduce the nominal contact area, it obtains the ability to regulate attachment during unidirectional loading. Two non-axisymmetric prototypes provide different design concepts for the artificial adhesives. It is hoped that this study will provide fresh viewpoints and innovations that contribute to the development of biologically inspired adhesives.

The role of D3-type cyclins is related to cytokinin and the bHLH transcription factor SPATULA in Arabidopsis gynoecium development.

MAIN CONCLUSION: We studied the D3-type cyclin function during gynoecium development in Arabidopsis and how they are related to the hormone cytokinin and the transcription factor SPATULA. Growth throughout the life of plants is sustained by cell division and differentiation processes in meristematic tissues. In Arabidopsis, gynoecium development implies a multiphasic process where the tissues required for pollination, fertilization, and seed development form. The Carpel Margin Meristem (CMM) is a mass of undifferentiated cells that gives rise to the gynoecium internal tissues, such as septum, ovules, placenta, funiculus, transmitting tract, style, and stigma. Different genetic and hormonal factors, including cytokinin, control the CMM function. Cytokinin regulates the cell cycle transitions through the activation of cell cycle regulators as cyclin genes. D3-type cyclins are expressed in proliferative tissues, favoring the mitotic cell cycle over the endoreduplication. Though the role of cytokinin in CMM and gynoecium development is highly studied, its specific role in regulating the cell cycle in this tissue remains unclear. Additionally, despite extensive research on the relationship between CYCD3 genes and cytokinin, the regulatory mechanism that connects them remains elusive. Here, we found that D3-type cyclins are expressed in proliferative medial and lateral tissues. Conversely, the depletion of the three CYCD3 genes showed that they are not essential for gynoecium development. However, the addition of exogenous cytokinin showed that they could control the division/differentiation balance in gynoecium internal tissues and outgrowths. Finally, we found that SPATULA can be a mechanistic link between cytokinin and the D3-type cyclins. The data suggest that the role of D3-type cyclins in gynoecium development is related to the cytokinin response, and they might be activated by the transcription factor SPATULA.

Papanicolaou test collection with the Papette brush or the spatula with cytobrush: A pragmatic study.

BACKGROUND: Cotesting with the Papanicolaou (Pap) and human papillomavirus tests detects most precancerous and cancerous lesions and increases the sensitivity for detecting high-grade precancerous and invasive cervical cancers compared with human papillomavirus testing alone. OBJECTIVE: To compare the use of the Papette brush (hereafter Papette) to the traditional spatula with endocervical brush (cytobrush) for cervical cancer screening. DESIGN: Pragmatic observational study. METHODS: Adult women aged 21-64 years who were eligible for a Papanicolaou test at a Midwest Community Internal Medicine practice underwent cervical cancer screening using the Papette or spatula with cytobrush from 18 August 2021 through 1 February 2022. Cluster sampling was used across the practice. Pathology reports were then analyzed to compare the number of satisfactory versus unsatisfactory results between the two collection techniques. RESULTS: We collected results for 756 Pap tests. The test results were satisfactory with the Papette 93.8% of the time compared with 93.0% for the spatula with cytobrush. CONCLUSION: The Papette is not inferior to a spatula with cytobrush as a collection method for Pap tests.

An expandable chamber for safe brain retraction: new technologies in the field of transcranial endoscopic surgery. / ä¸€ç§ç”¨äºŽå¤§è„‘ç‰µæ‹‰çš„å¯æ‰©å±•è ”ï¼šé¢ å† çª¥é•œæ‰‹æœ¯é¢†åŸŸçš„æ–°æŠ€æœ¯.

Neurosurgery is a highly specialized field: it often involves surgical manipulation of noble structures and cerebral retraction is frequently necessary to reach deep-seated brain lesions. There are still no reliable methods preventing possible retraction complications. The objective of this study was to design work chambers well suited for transcranial endoscopic surgery while providing safe retraction of the surrounding brain tissue. The chamber is designed to be inserted close to the intracranial point of interest; once it is best placed it can be opened. This should guarantee an appreciable workspace similar to that of current neurosurgical procedures. The experimental aspect of this study involved the use of a force sensor to evaluate the pressures exerted on the brain tissue during the retraction phase. Following pterional craniotomy, pressure measurements were made during retraction with the use of a conventional metal spatula with different inclinations. Note that, although the force values necessary for retraction and exerted on the spatula by the neurosurgeon are the same, the local pressure exerted on the parenchyma at the edge of the spatula at different inclinations varied greatly. A new method of cerebral retraction using a chamber retractor (CR) has been designed to avoid any type of complication due to spatula edge overpressures and to maintain acceptable pressure values exerted on the parenchyma.

Novel Roles of SPATULA in the Control of Stomata and Trichome Number, and Anthocyanin Biosynthesis.

The bHLH transcription factor SPATULA (SPT) has been identified as a regulator during different stages of Arabidopsis development, including the control of leaf size. However, the mechanism via which it performs this function has not been elucidated. To better understand the role of SPT during leaf development, we used a transcriptomic approach to identify putative target genes. We found putative SPT target genes related to leaf development, and to stomata and trichome formation. Furthermore, genes related to anthocyanin biosynthesis. In this work, we demonstrate that SPT is a negative regulator of stomata number and a positive regulator of trichome number. In addition, SPT is required for sucrose-mediated anthocyanin biosynthesis.

Understanding Humidity-Enhanced Adhesion of Geckos: Deep Neural Network-Assisted Multi-Scale Molecular Modeling.

A higher relative humidity leads to an increased sticking power of gecko feet to surfaces. The molecular mechanism responsible for this increase, however, is not clear. Capillary forces, water mediating keratin-surface contacts and water-induced softening of the keratin are proposed as candidates. In previous work, strong evidence for water mediation is found but indirect effects via increased flexibility are not completely ruled out. This article studies the latter hypothesis by a bottom-up coarse-grained mesoscale model of an entire gecko spatula designed without explicit water particles, so that capillary action and water-mediation are excluded. The elasticity of this model is adjusted with a deep neural network to atomistic elastic constants, including water at different concentrations. Our results show clearly that on nanoscopic flat surfaces, the softening of keratin by water uptake cannot nearly account for the experimentally observed increase in gecko sticking power. Here, the dominant mechanism is the mediation of keratin-surface contacts by intervening water molecules. This mechanism remains important on nanostructured surfaces. Here, however, a water-induced increase of the keratin flexibility may enable the spatula to follow surface features smaller than itself and thereby increase the number of contacts with the surface. This leads to an appreciable but not dominant contribution to the humidity-increased adhesion. Recently, by atomistic grand-canonical molecular dynamics simulation, the room-temperature isotherm is obtained for the sorption of water into gecko keratin, to the authors' knowledge, the first such relation for any beta-keratin. In this work, it relates the equilibrium water content of the keratin to the ambient relative humidity.

Density-dependence produces spurious relationships among demographic parameters in a harvested species.

Harvest of wild organisms is an important component of human culture, economy, and recreation, but can also put species at risk of extinction. Decisions that guide successful management actions therefore rely on the ability of researchers to link changes in demographic processes to the anthropogenic actions or environmental changes that underlie variation in demographic parameters. Ecologists often use population models or maximum sustained yield curves to estimate the impacts of harvest on wildlife and fish populations. Applications of these models usually focus exclusively on the impact of harvest and often fail to consider adequately other potential, often collinear, mechanistic drivers of the observed relationships between harvest and demographic rates. In this study, we used an integrated population model and long-term data (1973-2016) to examine the relationships among hunting and natural mortality, the number of hunters, habitat conditions, and population size of blue-winged teal Spatula discors, an abundant North American dabbling duck with a relatively fast-paced life history strategy. Over the last two and a half decades of the study, teal abundance tripled, hunting mortality probability increased slightly ( < 0.02 ), and natural mortality probability increased substantially ( > 0.1 ) at greater population densities. We demonstrate strong density-dependent effects on natural mortality and fecundity as population density increased, indicative of compensatory harvest mortality and compensatory natality. Critically, an analysis that only assessed the relationship between survival and hunting mortality would spuriously indicate depensatory mortality due to multicollinearity between abundance, natural mortality and hunting mortality. Our findings demonstrate that models that only consider the direct effect of hunting on survival or natural mortality can fail to accurately assess the mechanistic impact of hunting on population dynamics due to multicollinearity among demographic drivers. This multicollinearity limits inference and may have strong impacts on applied management actions globally.

Gecko Adhesion on Flat and Rough Surfaces: Simulations with a Multi-Scale Molecular Model.

A multiscale modeling approach is used to develop a particle-based mesoscale gecko spatula model that is able to link atomistic simulations and mesoscale (0.44 µm) simulations. It is used to study the detachment of spatulae from flat as well as nanostructured surfaces. The spatula model is based on microscopical information about spatulae structure and on atomistic molecular simulation results. Target properties for the coarse-graining result from a united-atom model of gecko keratin in periodic boundary conditions (PBC), previously developed by the authors. Pull-off forces necessary to detach gecko keratin under 2D PBC parallel to the surface are previously overestimated when only a small region of a spatula is examined. It is shown here that this is due to the restricted geometry (i.e., missing peel-off mode) and not model parameters. The spatula model peels off when pulled away from a surface, both in the molecular picture of the pull-off process and in the force-extension curve of non-equilibrium simulations mimicking single-spatula detachment studied with atomic force microscopy equipment. The force field and spatula model can reproduce experimental pull-off forces. Inspired by experimental results, the underlying mechanism that causes pull-off forces to be at a minimum on surfaces of varying roughnesses is also investigated. A clear sigmoidal increase in the pull-off force of spatulae with surface roughness shows that adhesion is determined by the ratio between spatula pad area and the area between surface peaks. Experiments showed a correlation with root-mean-square roughness of the surface, but the results of this work indicate that this is not a causality but depends on the area accessible.

Gene expression analysis during the fruit development in dehiscent and indehiscent Bixa orellana L. accessions.

Fruit morphology and dehiscence-related genes were analyzed in dehiscent N4P and dehiscent P12 Bixa orellana accessions. Fruit architecture (exocarp and pericarp cells, trichomes, vascular bundles, vesicles, and bixin cells) documented by Scanning electron microscopy (SEM) morphology, blue toluidine stain, and phloroglucinol and hydrochloric acid (PHCL) stain was similar in both accessions. Although, the dehiscent zone (DZ) was higher in the indehiscent P12 B. orellana accession, lignification values, obtained by phloroglucinol and hydrochloric acid stain, within the DZ remain was similar in both variants being lower at 34 days after floral anthesis in the dehiscent N4P B. orellana accession. Dehiscence-related genes APETALA (AP2), SHATTERPROOF (SHP), and SPATULA (SPT) were identified on the reported B. orellana transcriptome (SRX1117606). Real-time quantitative polymerase chain reaction primers build by using these genes allow observing a differential expression during six fruit development stages. In both B. orellana accessions, the AP2 transcripts have a reduced expression, whereas the SHP transcripts were significantly higher during the first two days and ten days of development. SPT transcripts show an expression differential between both accessions being significantly higher in the dehiscent N4P, peaking with 9.66% at 42 days after floral anthesis (DAFA) of development. SPT transcription profile suggested that this gene has an important role during the fruit opening in the dehiscent N4P B. orellana accession. Supplementary Information: The online version contains supplementary material available at 10.1007/s12298-022-01180-w.

Pap Smear Collection and Preparation: Key Points.

Cytology is the science of study of cells. It is derived from the Greek word "cytos" which means cells. The cells of the cervicovaginal epithelium are continuously evolving. The mature cells reach the surface and are then exfoliated. Initially, these exfoliated cells were collected from the posterior fornix, which showed cells from endocervix, ectocervix, and the vaginal epithelium. Hence, it was known as the exfoliative vaginal cytology. But now, the cells are taken directly by scraping the ecto and the endocervix. A variety of sampling devices are available in the market. The basic aim is to augment sampling of the complete transformation zone (TZ) as well as the squamocolumnar junction (SCJ) and cause least possible trauma to the cervical and endocervical epithelium during its use. The SCJ is of crucial significance for cervical cancer pathogenesis. Most of the precancerous changes take place within the TZ and at the SCJ. Hence, the collection of cells from this area is of utmost importance. The reliability of cervical cytology for the detection of precancerous lesions also strongly depends on immediate wet fixation of the smear. Therefore, the gynecologists or the paramedics who perform the conventional Pap smears must not only be trained in the art of cell collection and smearing of the material onto the glass slides but also learn immediate wet fixation of the cervical cells. Liquid-based preparations have made all these steps relatively easy for them as the design of the Cervex brush is such that it mostly ensures the sampling of the complete TZ and the SCJ. Pre-fixation of cells occurs in the vial containing a weak fixative and the transfer of cells onto the glass slide is standardized by the automated stations designed for this purpose. This chapter gives an in depth description of the prerequisites and precautions while collecting and preparing a Pap smear with different devices, especially for settings where conventional smears are still the norm. Instructions for women undergoing Pap smear and the medical personnel who conduct this test are also highlighted.

Mini Review: Comparison of Bio-Inspired Adhesive Feet of Climbing Robots on Smooth Vertical Surfaces.

Developing climbing robots for smooth vertical surfaces (e.g., glass) is one of the most challenging problems in robotics. Here, the adequate functioning of an adhesive foot is an essential factor for successful locomotion performance. Among the various technologies (such as dry adhesion, wet adhesion, magnetic adhesion, and pneumatic adhesion), bio-inspired dry adhesion has been actively studied and successfully applied to climbing robots. Thus, this review focuses on the characteristics of two different types of foot microstructures, namely spatula-shaped and mushroom-shaped, capable of generating such adhesion. These are the most used types of foot microstructures in climbing robots for smooth vertical surfaces. Moreover, this review shows that the spatula-shaped feet are particularly suitable for massive and one-directional climbing robots, whereas mushroom-shaped feet are primarily suitable for light and all-directional climbing robots. Consequently, this study can guide roboticists in selecting the right adhesive foot to achieve the best climbing ability for future robot developments.

Comparative study on the adequacy of cervical smears using wooden Ayre's spatula, VS Papcone® sampling device.

This is a comparative study on the adequacy of cervical smears obtained using the Papcone® sampling device or wooden Ayre's spatula conducted from two tertiary health facilities -- Nnamdi Azikiwe University Teaching Hospital Nnewi and Chukwuemeka Odumegwu Ojukwu University Teaching Hospital Awka, in Anambra State, Nigeria. Slides from smears obtained using both devices were read by a cytopathologist blinded for the study. The primary outcome was the proportion of smears with an adequate endocervical component. Significantly higher adequate cervical smears were obtained in 177/192 (92.2%) women using the Papcone® sampling device, compared to 152/192 (79.2%) using wooden Ayre's spatula (p < 0.001). Kappa analysis showed moderate inter-rater agreement between the two devices. We recommend the use of the Papcone device when it is available, as the adequacy of cervical smears obtained with the Papcone® was better than that obtained using wooden Ayre's spatula.

Promoter analysis of the SPATULA (FvSPT) and SPIRAL (FvSPR) genes in the woodland diploid strawberry (Fragaria vesca L.).

The aim of this study was to identify transcription factor (TF) binding sites and cis-regulatory elements (CREs) on the promoters of FvSPR1-like2 (SPIRAL) and FvSPT (SPATULA) genes in the woodland diploid strawberry (Fragaria vesca L.). We identified: (1) MYB59, WRKY25 and WRKY8 TFs which play a role in ethylene signaling; (2) ARF family of TFs which play a role in ARF-mediated auxin signaling on the promoter of FvSPR1-like2 gene; (3) ARR family of TFs which play a role in cytokinin signaling; (4) ERF family of TFs which play a role in ethylene signaling on the promoter of FvSPT. This bioinformatic analysis of TFs and CREs may provide a better understanding of the function of genes involved in, and the mechanism underlying, non-climateric ripening during strawberry fruit maturation.

[Brain retraction injury]. / Retraktsionnaya travma golovnogo mozga.

This review is devoted to various techniques for reduction of brain damage during retraction. Searching for reports was carried out in Russian and English languages using the PubMed database (n=721) without restrictions on language, date and study design according to the following keywords: «brain retraction injury¼, «spatula brain retractors¼, «tubular brain retractors¼, «retractorless neurosurgery¼. Primary screening and exclusion of duplicate manuscripts allowed us to single out the main group of articles (n=121). Some reports were excluded due to non-compliance with inclusion criteria (no description of methods, few references and insufficient data). The final list included 32 studies which were represented by cohort studies, retrospective analyses of surgical interventions, as well as experimental and laboratory studies. Small number of publications did not allow us to obtain unambiguous conclusions. Further research is required to reduce brain retraction trauma.

Surgical fixation by mesh plate and intraoperative safe techniques for the manubrium sterni.

Plate osteosynthesis for oblique fracture of the manubrium sterni is quite rare. We present a case of a 37-year-old man with oblique fracture of the manubrium sterni caused by a traumatic injury. He was operated on using a variable-angle locking compression plate Mesh Plate 2.4/2.7 and had a good postoperative result. We also discuss intraoperative safe techniques such as use of a cement spatula for reduction support tools and depth-limited drilling to prevent excess drilling of the opposite cortex.

[Does instrumental delivery have an influence on the need for orthodontic treatment?] / L'accouchement instrumental a-t-il une influence sur le besoin de traitement orthodontique ?

The objective of this comparative retrospective cohort performed on 202 patients was to evaluate the influence of instrumental extraction (forceps, suction cup, spatula) during delivery on the need for orthodontic treatment. Questionnaires on the type of delivery were distributed in three different structures. The need for treatment was assessed using the IOTN indicator (Index of Orthodontic Treatment Need). The groups were compared by statistical tests at the significance level of 5 %. 202 patients were included (51 in the group « instrumental delivery ¼, 151 in the control group). With an average IOTN of 3.3 in the « instrumental delivery ¼ group versus 2.5 in the « non-instrumental delivery ¼ group, the difference between the two groups is statistically significant (p = 0.00015). Since the need for orthodontic treatment is significantly higher in patients born by instrumental delivery compared to patients born without instrumental support, instrumental extraction is therefore a risk factor in orthodontics, diagnosis and orthodontic treatment may be indicated in these patients. In addition, provided that it is proven effective, early osteopathic management may be recommended.

Nitrate Promotes Germination Under Inhibition by NaCl or High Concentration of Glucose.

Seed germination, one of the most important stages in a plant's life cycle, can be affected by abiotic stresses, such as salinity. The plant hormone abscisic acid (ABA) and high concentrations of glucose are also known to inhibit germination. In contrast, nitrate is known to stimulate germination in many plants. However, this stimulatory effect has not yet been investigated in the presence of inhibitory effects caused by abiotic stresses, ABA, and glucose. In this study, we show that nitrate can alleviate the inhibitory effects of sodium chloride (NaCl) or high concentrations of glucose on seed germination in Arabidopsis, while it was not able to promote germination that was inhibited by exogenous ABA and mannitol (an inducer of osmotic stress). An analysis of the gene expression involved in the regulation of germination showed that GA20ox1, encoding the gibberellin (GA) synthesis enzyme, SPATULA (SPT), encoding a bHLH transcription factor, and CYP707A2, encoding an ABA catabolic enzyme, were significantly upregulated by the addition of KNO3 in the presence of NaCl or glucose. Our results suggest the possibility that these genes are involved in the nitrate-mediated control of seed germination in the presence of NaCl or glucose.

Suction Spatula for Surgery of Vestibular Schwannomas in Supine Position: Technical Note.

BACKGROUND: Resection of vestibular schwannomas with good functional outcome remains a neurosurgical challenge. In this study, we report on our initial experience with a suction spatula, which allows free bimanual dissection of small tumors in a clear, bloodless surgical field in supine position. METHODS: Forty-one patients underwent vestibular schwannoma surgery in supine position, using a suction spatula. To analyze its feasibility, 11 aspects of the device were compared with the regular retractor. RESULTS: The suction spatula was successfully applied in all surgeries. Compared with a common spatula, the suction spatula showed superior performance during meatotomy, microsurgical and endoscopic tumor dissection, and management of bleedings. We noted no difference in ergonomics, compatibility, instrumental conflict, costs, reusability, and sterilization issues. Minor performance was related to its thickness/size. There were no significant disadvantages according to our data. There were no surgical complications related to this device. CONCLUSIONS: The main advantage of the suction spatula is in the treatment of small, mainly intrameatal vestibular schwannomas in supine patient position. It gives the surgeon a "third hand" while enabling a continuous bimanual dissection with 2 microinstruments without the use of a regular suction tip.

Expression of gynoecium patterning transcription factors in Aristolochia fimbriata (Aristolochiaceae) and their contribution to gynostemium development.

BACKGROUND: In Aristolochia (Aristolochiaceae) flowers, the congenital fusion of the anthers and the commissural, stigmatic lobes forms a gynostemium. Although the molecular bases associated to the apical-basal gynoecium patterning have been described in eudicots, comparative expression studies of the style and stigma regulatory genes have never been performed in early divergent angiosperms possessing a gynostemium. RESULTS: In this study, we assess the expression of five genes typically involved in gynoecium development in Aristolochia fimbriata. We found that all five genes (AfimCRC, AfimSPT, AfimNGA, AfimHEC1 and AfimHEC3) are expressed in the ovary, the placenta, the ovules and the transmitting tract. In addition, only AfimHEC3, AfimNGA and AfimSPT are temporarily expressed during the initiation of the stigma, while none of the genes studied is maintained during the elaboration of the stigmatic surfaces in the gynostemium. CONCLUSIONS: Expression patterns suggest that CRC, HEC, NGA and SPT homologs establish ovary and style identity in Aristolochia fimbriata. Only NGA,HEC3 and SPT genes may play a role in the early differentiation of the stigmatic lobes, but none of the genes studied seems to control late stigma differentiation in the gynostemium. The data gathered so far raises the possibility that such transient expression early on provides sufficient signal for late stigma differentiation or that unidentified late identity genes are controlling stigma development in the gynostemium. Our data does not rule out the possibility that stigmas could correspond to staminal filaments with convergent pollen-receptive surfaces.