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Understanding lattice deformations is crucial in determining the properties of nanomaterials, which can become more prominent in future applications ranging from energy harvesting to electronic devices. However, it remains challenging to reveal unexpected deformations that crucially affect material properties across a large sample area. Here, we demonstrate a rapid and semi-automated unsupervised machine learning approach to uncover lattice deformations in materials. Our method utilizes divisive hierarchical clustering to automatically unveil multi-scale deformations in the entire sample flake from the diffraction data using four-dimensional scanning transmission electron microscopy (4D-STEM). Our approach overcomes the current barriers of large 4D data analysis without a priori knowledge of the sample. Using this purely data-driven analysis, we have uncovered different types of material deformations, such as strain, lattice distortion, bending contour, etc., which can significantly impact the band structure and subsequent performance of nanomaterials-based devices. We envision that this data-driven procedure will provide insight into materials’ intrinsic structures and accelerate the discovery of materials.

Objective: Although relatively costly and non-scalable, non-invasive neuromodulation interventions are treatment alternatives for neuropsychiatric disorders. The recent developments of highly-deployable transcranial electric stimulation (tES) systems, combined with mobile-Health technologies, could be incorporated in digital trials to overcome methodological barriers and increase equity of access. The study aims are to discuss the implementation of tES digital trials by performing a systematic scoping review and strategic process mapping, evaluate methodological aspects of tES digital trial designs, and provide Delphi-based recommendations for implementing digital trials using tES.Methods: We convened 61 highly-productive specialists and contacted 8 tES companies to assess 71 issues related to tES digitalization readiness, and processes, barriers, advantages, and opportunities for implementing tES digital trials. Delphi-based recommendations (>60% agreement) were provided.Results: The main strengths/opportunities of tES were: (i) non-pharmacological nature (92% of agreement), safety of these techniques (80%), affordability (88%), and potential scalability (78%). As for weaknesses/threats, we listed insufficient supervision (76%) and unclear regulatory status (69%). Many issues related to methodological biases did not reach consensus. Device appraisal showed moderate digitalization readiness, with high safety and potential for trial implementation, but low connectivity.Conclusions: Panelists recognized the potential of tES for scalability, generalizability, and leverage of digital trials processes; with no consensus about aspects regarding methodological biases. Significance: We further propose and discuss a conceptual framework for exploiting shared aspects between mobile-Health tES technologies with digital trials methodology to drive future efforts for digitizing tES trials. (C) 2022 International Federation of Clinical Neurophysiology. Published by Elsevier B.V. All rights reserved.

Inorganic nanomaterials are often depicted as rigid structures whose shape is permanent. However, forces that are ordinarily considered weak can exert sufficient stress at the nanoscale to drive mechanical deformation. Here, we leverage van der Waals (VdW) interactions to mechanically reshape inorganic nanostructures from planar to curvilinear. Modified plate deformation theory shows that high aspect ratio 2D particles can be plastically deformed via VdW forces. Informed by this finding, silver nanoplates were deformed over spherical iron oxide template particles, resulting in distinctive bend contour patterns in bright field (BF) transmission electron microscopy (TEM) images. High resolution (HR) TEM images of deformed areas reveal the presence of highly strained bonds in the material. Finally, we show the distance between two nearby template particles allows for the engineering of several distinct curvilinear morphologies. This work challenges the traditional view of nanoparticles as static objects and introduces methods for post-synthetic mechanical shape control.

Abstract Early haemorrhage control and minimizing the time to definitive care have long been the cornerstones of therapy for patients exsanguinating from non-compressible haemorrhage (NCH) after penetrating injuries, as only basic treatment could be provided on scene. However, more recently, advanced on-scene treatments such as the transfusion of blood products, resuscitative thoracotomy (RT) and resuscitative endovascular balloon occlusion of the aorta (REBOA) have become available in a small number of pre-hospital critical care teams. Although these advanced techniques are included in the current traumatic cardiac arrest algorithm of the European Resuscitation Council (ERC), published in 2021, clear guidance on the practical application of these techniques in the pre-hospital setting is scarce. This paper provides a scoping review on how these advanced techniques can be incorporated into practice for the resuscitation of patients exsanguinating from NCH after penetrating injuries, based on available literature and the collective experience of several helicopter emergency medical services (HEMS) across Europe who have introduced these advanced resuscitation interventions into routine practice. Graphical Abstract

Although relatively costly and non-scalable, non-invasive neuromodulation interventions are treatment alternatives for neuropsychiatric disorders. The recent developments of highly-deployable transcranial electric stimulation (tES) systems, combined with mobile-Health technologies, could be incorporated in digital trials to overcome methodological barriers and increase equity of access. We convened 61 highly-productive specialists and contacted 8 tES companies to assess 71 issues related to tES digitalization readiness, and processes, barriers, advantages, and opportunities for implementing tES digital trials. Delphi-based recommendations (>60% agreement) were provided. Device appraisal showed moderate digitalization readiness, with high safety and the possibility of trial implementation, but low connectivity. Panelists recognized the potential of tES for scalability, generalizability, and leverage of digital trials processes; although they reached no consensus about aspects regarding methodological biases. We further propose and discuss a conceptual framework for exploiting shared aspects between mobile-Health tES technologies with digital trials methodology to drive future efforts for digitizing tES trials.Graphical Abstract. Consensus Roadmap(A) Recruitment process. The study procedure started with defining the components of the research problem by the core research team. After defining the problems, two different sets of participants (the steering committee (SC) including key leaders of the field identified by the core team and the expert panel (EP) as a more diverse group of experts identified based on the number of publications based on a systematic review) were identified and were invited to participate in a Delphi study. The study facilitators (first and last authors) led the communications with the SC to design the initial questionnaire through an iterative approach. (B) Evidence synthesis: To collect the available evidence, companies producing portable tES (ptES) devices were contacted, based on the companies suggested by the SC and EP to provide details about the available devices. For mapping methodological processes of digitizing tES trials, two distinct strategies were performed and embedded into the questionnaire, namely SIPOC (Suppliers, Inputs, Process, Outputs, and Customer) and SWOT (Strengths, Weaknesses, Opportunities, and Threats) assessment were performed and embedded into the questionnaire. (C) Consensus development: In the next phase, the questionnaire was validated and finalized via collecting and summarizing opinions. Afterward, the SC and EP responded to the final questionnaire, and results were analyzed providing a list of recommendations for running tES digital trials based on a pre-registered consensus threshold.

Introduction Autonomic arousal is believed to be an underlying reinforcer for problematic gambling behavior. Theories suggests that near-misses (outcomes falling just short of a true win) are structural characteristics affecting emotion and motivation while increasing gambling persistence. Objectives Psychophysiological responses to different outcomes in gambling were investigated in a community-based sample of young adults. Furthermore, sex differences in responses to different gambling outcomes were investigated. Methods Young adults (n=270) performed a simplified virtual slot machine producing wins, two types of near-misses (before/after payline) and full-misses, with simultaneous measurements of heart rate (HR) and skin conductance responses (SCR). Self-reports of perceived chance of winning, pleasure and motivation to play were given by the participants on each trial. Results Near-misses were associated with the largest HR acceleration compared to wins and full-misses, and larger HR deceleration and SCRs compared to full-misses. Differential autonomic and subjective reports were observed for near-misses subtypes, suggesting that near-misses are processed differently depending on their position before or after payline. Females showed larger SCR responses and increased motivation following wins compared to males. Conclusions Slot machine gambling outcomes elicit differential physiological and subjective responses in young adults. Specifically, near-misses produce larger autonomic responses compared to regular full-misses. However, near-misses are complex, multifaceted events producing various emotional responses depending on their characterization. Males and females respond differently to wins, highlighting the importance of considering sex differences in experimental research on autonomic responses in gambling. Disclosure No significant relationships.

Inorganic nanomaterials are often depicted as rigid structures whose shape is permanent. However, forces that are ordinarily considered weak can exert sufficient stress at the nanoscale to drive mechanical deformation. Here, we leverage van der Waals (VdW) interactions to mechanically reshape inorganic nanostructures from planar to curvilinear. Modified plate deformation theory shows that high aspect ratio 2D particles can be plastically deformed via VdW forces. Informed by this finding, silver nanoplates were deformed over spherical iron oxide template particles, resulting in distinctive bend contour patterns in bright field (BF) transmission electron microscopy (TEM) images. High resolution (HR) TEM images of deformed areas reveal the presence of highly strained bonds in the material. Finally, we show the distance between two nearby template particles allows for the engineering of several distinct curvilinear morphologies. This work challenges the traditional view of nanoparticles as static objects and introduces methods for post-synthetic mechanical shape control.

Liquid-phase transmission electron microscopy (LP-TEM) is a powerful characterization tool for probing the dynamics of nanometer-scale systems in a solvated environment. When the energetic electron beam (80–300 kV) interacts with the solvent, radiolysis occurs, generating highly reactive species that interact with the sample. While these species are often considered harmful and great efforts are taken to mitigate their influence, many of these radiolytic products, such as hydroxyl radicals and solvated electrons, are crucially relevant to several areas of energy research. In this Perspective, we propose a paradigm shift wherein solvent-derived, reactive radiolytic species generated by the electron beam are viewed as a tool for rational chemical perturbation of a material system rather than as a source of error to minimize. With an increased understanding of and control over the chemical kinetics governing the distribution of radiolytic species, LP-TEM is poised to allow for direct imaging of chemically dr...

The current management of severely injured patients includes damage control resuscitation strategies that minimise the use of crystalloids and emphasise earlier transfusion of red blood cells (RBC) to prevent coagulopathy. In 2012, London's air ambulance (LAA) became the first UK civilian pre-hospital service to routinely carry RBC to the trauma scene.To investigate the effect of pre-hospital RBC transfusion (phRTx) on overall blood product consumption.A retrospective trauma database study compares before implementation with after implementation of phRTx in exsanguinating trauma patients transported directly to one major trauma centre. Pre-hospital deaths were excluded. Univariate and multivariate Poisson regression analyses on data subject to multiple imputation were conducted.We included 137 and 128 patients in the before and after the implementation of phRTx groups, respectively. LAA transfused 304 RBC units (median 2, inter quartile range 1-3). We found a significant reduction in total RBC usage and reduced early use of platelets and fresh-frozen plasma (FFP) after the implementation of phRTx in both univariate (P 0·001) and multivariate analyses (P 0·001). No immediate adverse transfusion reactions were identified.Pre-hospital trauma transfusion practice is feasible and associated with overall reduced RBC, platelets and FFP consumption.

Bei der Therapie des Endometriumkarzinoms steht heute der operative Weg im Vordergrund und ermoglicht den stadiengerechten Einsatz zusatzlicher adjuvanter Masnahmen. Die Aufgabe der Diagnostik besteht darin, das operative Vorgehen moglichst individuell festzulegen. Der transvaginale Ultraschall ist eine kostengunstige, zumeist schmerz- und komplikationslose Methode in der Diagnostik des Endometriumkarzinoms. Sonographisch beurteilt werden Endometriumdicke, Echostruktur und Endometriumbegrenzung sowie – falls vorhanden – eine intrakavitare Flussigkeitsansammlung. Neben der konventionellen transvaginalen Sonographie (TVS) besteht die Moglichkeit einer Dignitatsbeurteilung mittels Farb- und Pulsdopplersonographie, z. B unter Verwendung von Pulsatility-Index und Resistance-Index. Bei der praoperativen Stadieneinteilung stellt die MRT bezuglich der Myometriuminfiltration und des zervikalen Befalls im Vergleich zu TVS und CT die praziseste Methode dar.

The effects of carbocyclic thromboxane A(2) (cTXA(2); 10(-6) mol L(-1)) on membrane potential and cytosolic Ca(2+) concentration were measured with the whole-cell patch-clamp or the fura-2 method, respectively, at rat myenteric ganglia. cTXA(2) caused a hyperpolarization of myenteric neurones from -19.3 +/- 2.5 to -29.3 +/- 2.3 mV. In addition, the eicosanoid potentiated the carbachol-induced depolarization from 4.2 +/- 1.0 mV under control conditions to 11.1 +/- 1.1 mV in the presence of the cTXA(2) (n = 9). The hyperpolarization was abolished by internal application of CsCl (140 mmol L(-1)), a non-selective blocker of K(+) channels, or EGTA (11 mmol L(-1)in the pipette solution), a chelator of intracellular Ca(2+). A similar inhibition was observed in the presence of charybdotoxin (10(-7) mol L(-1)). Fura-2 imaging experiments revealed a cTXA(2)-evoked increase in the intracellular Ca(2+) concentration as indicated by a rise in the fura-2 ratio signal. This response was mediated by a release of Ca(2+) from intracellular stores as sarcoplasmic-endoplasmic reticulum Ca(2+)-ATPase blockade with cyclopiazonic acid (5 x 10(-5) mol L(-1)) completely abolished the response to cTXA(2). A similar inhibition was observed after blockade of phospholipase C with U-73122 (10(-5) mol L(-1)). These results suggest an activation of Ca(2+)-activated K(+) channels by cTXA(2) after stimulation of phospholipase C.

Short-chain fatty acids produced by the bacterial fermentation of carbohydrates are present in high concentrations within the colonic lumen and have been shown to alter the excitability of enteric neurones. The present study was designed to investigate the mechanisms of butyrate-induced changes in membrane potential of myenteric neurones. Myenteric neurones from 4-10-day-old rats were isolated from the small and large intestine by an enzymatic digestion with collagenase and kept in culture. Membrane potential was measured with the whole-cell patch-clamp technique and the intracellular Ca2+ concentration was measured with the fura-2 method. The short-chain fatty acid butyrate (10-100 mmol L(-1)) induced a reversible and concentration-dependent hyperpolarization of the membrane with a half-maximal effect at 30 mmol L(-1). The hyperpolarization evoked by butyrate (50 mmol L(-1)) was strongly inhibited by charybdotoxin (10(-7) mol L(-1)), a specific blocker of Ca2+ -dependent K+ channels. The butyrate-induced hyperpolarization was resistant against blockade of phospholipase C by U-73122 (10(-5) mol L(-1)), and resistant against inclusion of heparin (6 x 10(-6) mol L(-1)), an inositol-1,4,5-trisphosphate receptor antagonist, in the patch-pipette. In contrast, ruthenium red (3 x 10(-5) mol L(-1)), an inhibitor of ryanodine receptors, significantly reduced both the hyperpolarization of the membrane as well as the increase in the intracellular Ca2+ concentration evoked by butyrate. Even in neurones permeabilized with saponin (10 mg L(-1)), butyrate was able to stimulate a release of stored intracellular Ca2+ suggesting a direct action of the short-chain fatty acid at the stores without mediation of a soluble intracellular second messenger.

Aims Tumour necrosis factor-alpha (TNF-alpha) plays a central role in the pathophysiology of inflammatory bowel disease. The present experiments were designed to characterize the action of this cytokine on enteric neurones. Methods Myenteric ganglia from newborn rats were treated for 20 h with TNF-alpha (100 ng mL(-1)) and studied with the patch-clamp technique. Results Control neurones showed a membrane potential of -34.6 +/- 2.2 mV (n = 22), whereas TNF-alpha-treated cells exhibited a membrane potential of -50.8 +/- 3.5 mV (n = 25). The depolarization evoked by carbachol (50 microm) was potentiated from 5.2 +/- 0.7 mV (n = 6) in control neurones to 27.5 +/- 2.0 mV (n = 10) in TNF-alpha-treated cells. This effect was mimicked by 1,1-dimethyl-4-phenylpiperazinium iodide, but not by bethanechol. The changes in basal membrane potential and in the nicotinic receptor response were suppressed by the non-selective cyclooxygenase (COX) inhibitor indomethacin (10 microm), and the COX II-specific inhibitor, nimesulide (100 microm), whereas the COX-I selective inhibitor SC-560 (5 microm) and the proteintyrosinekinase inhibitor genistein (50 microm) only partially inhibited the action of TNF-alpha. Staining of the ganglionic cells with an antibody against the transcription factor STAT5 revealed that TNF-alpha induced a nuclear translocation of STAT5 in non-neuronal cells. Conclusion TNF-alpha changes the electrophysiological properties of myenteric neurones via cyclooxygenase metabolites and protein tyrosine phosphorylation; the cells primarily responding to the cytokine seem to be non-neuronal cells in the ganglion culture, which respond with a nuclear STAT5 translocation suggesting an action on gene transcription.

Learning representations that disentangle hidden explanatory factors in data has proven beneficial for effective pattern classification. Slow feature analysis (SFA) is a nonlinear dimensionality reduction technique that provides a useful representation for classification if the training data is sequential and transitions between classes are rare. The pattern discrimination ability of SFA has been attributed to the equivalence of linear SFA and linear discriminant analysis (LDA) under certain conditions. LDA, however, is often outperformed by locality preserving projections (LPP) when the data lies on or near a low-dimensional manifold. Here, we take a unified manifold learning perspective on LPP, LDA and SFA. We suggest that the discrimination ability of SFA is better explained by its relation to LPP than to LDA, and give an example of a situation where linear SFA outperforms LDA. We then propose a novel supervised manifold learning architecture that combines hierarchical nonlinear expansions, as commonly used for SFA, with supervised LPP. It learns a nonlinear parametric data representation that explicitly takes both the class labels and the manifold structure of the data into account. As an experimental validation, we show that this approach outperforms previously proposed models on the NORB object recognition dataset.

Genital findings in sexually abused prepubertal girls. Childhood sexual abuse is defined as the involvement of dependent, developmentally immature children and adolescents in sexual activities that they do not fully comprehend, to which they are unable to give informed consent or that violate the social taboos of family roles. Essential to the diagnosis of sexual abuse is an awareness of the problem and acknowledgement of its manifestations. The evaluation of the sexually abused girl usually is performed in a pediatric and adolescent gynecology outpatient department. Thus, the gynecologist will be part of a multidisciplinary approach to the problem and will need to be competent in the basic skills of history taking, physical examination, selection of laboratory tests und differential diagnosis. Findings secondary to sexual abuse are often subtle. Acute tears or bruisings are rare, because force is seldom part of sexual acts committed against a child. A vaginal opening of greater than 5 mm is not common and may indicate vaginal penetration. An intact hymen not necessarily exclude vaginal intercourse. Lack of physical evidence never rules out abuse because sexual acts may leave no physical findings. Language: de

To overcome the limitations of the state-of-the-art influenza surveillance systems in Europe, we established in 2008 a European-wide consortium aimed at introducing an innovative information and communication technology approach for a web-based surveillance system across different European countries, called Influenzanet. The system, based on earlier efforts in The Netherlands and Portugal, works with the participation of the population in each country to collect real-time information on the distribution of influenza-like illness cases through web surveys administered to volunteers reporting their symptoms (or lack of symptoms) every week during the influenza season. Such a large European-wide web-based monitoring infrastructure is intended to rapidly identify public health emergencies, contribute to understanding global trends, inform data-driven forecast models to assess the impact on the population, optimize the allocation of resources, and help in devising mitigation and containment measures. In this article, we describe the scientific and technological issues faced during the development and deployment of a flexible and readily deployable web tool capable of coping with the requirements of different countries for data collection, during either a public health emergency or an ordinary influenza season. Even though the system is based on previous successful experience, the implementation in each new country represented a separate scientific challenge. Only after more than 5 years of development are the existing platforms based on a plug-and-play tool that can be promptly deployed in any country wishing to be part of the Influenzanet network, now composed of The Netherlands, Belgium, Portugal, Italy, the UK, France, Sweden, Spain, Ireland, and Denmark.

From 1982 to 1993 67 diabetic women attended the University Women's Hospital obstetric clinic at Wurzburg. These women were separated into two groups: group 1 (inpatient group) delivered between 1/82 and 7/87, group 2 (outpatient group) delivered between 8/87 and 4/93. Between 1982 and 1987 we used extensive inpatient care. But did not so after 1987. The fetus was monitored by ultrasound scans, cardiotocography, oxytocin stress test and doppler measurements. Nearly all patients used home blood glucose monitoring. We compared blood glucose levels, mode of delivery and fetal outcome for the two groups. There was no significant difference in the average blood glucose levels between the two groups. Cesarean section rates (37%) and gestational age at delivery (37 weeks) were similar in both groups. Fetal macrosomia (birth weight > 4000 g) occured more frequently in the outpatient group (group l: 4%, group 2: 25%,P

Hierarchical Temporal Memory is a biologically-inspired framework that can be used to learn invariant representations of patterns. Classical HTM learning is mainly unsupervised and once training is completed the network structure is frozen, thus making further training quite critical. In this paper we develop a novel technique for HTM (incremental) supervised learning based on error minimization. We prove that error backpropagation can be naturally and elegantly implemented through native HTM message passing based on Belief Propagation. Our experimental results show that a two stage training composed by unsupervised pre-training + supervised refinement is very effective. This is in line with recent findings on other deep architectures.

Our aim was to define the dynamics in collagen concentrations in the large bowel wall following decompression of experimental obstruction.Colonic obstruction was created in 28 male rats by the placement of a silicone ring around the distal colon. The ring was removed after 4 days to mimic endoscopical decompression by stent deployment. Colon circumference and collagen concentration were measured proximal to the obstructed segment immediately and at 3 and 10 days after decompression. The corresponding colonic sites of 23 sham-operated and eight nonoperated control animals were subjected to identical analyses.Four days of obstruction resulted in a more than twofold increase in colonic circumference (20 vs 8 mm), with a concomitant 43% reduction (P = 0.001) in collagen concentration in the bowel wall proximal to the obstruction compared with sham animals. Three days after decompression, collagen concentrations remained reduced (P0.05), while there was no significant difference after 10 days with either sham-operated or nonoperated controls. Colonic circumference of the obstructed colon remained slightly distended (11 mm) on day 10 and tended to correlate (r(S) = 0.51, P = 0.053) with total matrix metalloproteinase activity.The marked reduction in collagen concentration in an experimentally obstructed colon is normalized 10 days after decompression. These findings may have clinical implications for the timing of surgical resection.

The enzyme hormone-sensitive lipase (HSL) is produced and is active in pancreatic beta cells. Because lipids are known to play a crucial role in normal control of insulin release and in the deterioration of beta cell function, as observed in type 2 diabetes, actions of HSL in beta cells may be critical. This notion has been addressed in different lines of HSL knockout mice with contradictory results.To resolve this, we created a transgenic mouse lacking HSL specifically in beta cells, and characterised this model with regard to glucose metabolism and insulin secretion, using both in vivo and in vitro methods.We found that fasting basal plasma glucose levels were significantly elevated in mice lacking HSL in beta cells. An IVGTT at 12 weeks revealed a blunting of the initial insulin response to glucose with delayed elimination of the sugar. Additionally, arginine-stimulated insulin secretion was markedly diminished in vivo. Investigation of the exocytotic response in single HSL-deficient beta cells showed an impaired response to depolarisation of the plasma membrane. Beta cell mass and islet insulin content were increased, suggesting a compensatory mechanism, by which beta cells lacking HSL strive to maintain normoglycaemia.Based on these results, we suggest that HSL, which is located in close proximity of the secretory granules, may serve as provider of a lipid-derived signal essential for normal insulin secretion.

Excitonics is a rapidly expanding field of nanophotonics in which the harvesting of photons, ensuing creation and transport of excitons via Forster resonant energy transfer (FRET), and subsequent charge separation or photon emission has led to the demonstration of excitonic wires, switches, Boolean logic and light harvesting antennas for many applications. FRET funnels excitons down an energy gradient resulting in energy loss with each step along the pathway. Conversely, excitonic energy up conversion via up conversion nanoparticles (UCNPs), although currently inefficient, serves as an energy ratchet to boost the exciton energy. Although FRET-based up conversion has been demonstrated, it suffers from low FRET efficiency and lacks the ability to modulate the FRET. We have engineered an up conversion FRET-based switch by combining lanthanide-doped UCNPs and fluorophores that demonstrates excitonic energy up conversion by nearly a factor of 2, an excited state donor to acceptor FRET efficiency of nearly 25%, and an acceptor fluorophore quantum efficiency that is close to unity. These findings offer a promising path for energy up conversion in nanophotonic applications including artificial light harvesting, excitonic circuits, photovoltaics, nanomedicine, and optoelectronics.

The effect of the steroid hormone progesterone on transepithelial sodium transport was measured in confluent monolayers of the A6-cell line from Xenopus kidney. Apical permeabilization with Amphotericin B enabled us to measure the Na+/K+-pump current, and current-fluctuation analysis was used to analyze changes in apical channel density and gating characteristics. Basolateral progesterone (22.2 microM) had a rapid inhibitory effect on the Na+/K+-pump current, and a corresponding decrease in Na+ channel density. The effect occurred within some minutes and took about 50 min to reach a new steady state, in which 45% of the macroscopic current (ISC) was inhibited. Progesterone also inhibits the hypo-osmotic stimulation of Na+ channels which occurs in untreated monolayers. Compared with the known effects of adrenal steroids, our results show a rapid inhibitory action of a steroid hormone on Na+ absorption. The time profile of the progesterone effect suggests, at least in the first minutes, a non-genomic action of progesterone.

The endostatin precursor collagen XVIII is expressed at high levels in human livers, the main source being hepatocytes. We have studied the regulatory elements in the promoter 2 of the Col18a1 gene that directs the transcription of the NC1-517 variant of collagen alpha1(XVIII), which is the main form expressed in the liver. The 5'-flanking region of Col18a1 gene was cloned, and a series of 5'-deletions from -3286 bp to +285 bp were linked to the luciferase reporter gene. Transfection experiments in HepG2 cells allowed to identify a silencer-like element containing putative HNF1 and HNF3 sites and activator elements containing stretches of GC-rich sequences. Another putative HNF3 site in close apposition to a NF1/CTF site was localized upstream of the silencer-like element. Cotransfection experiments showed that the Col18a1 promoter 2 was transactivated by Sp1 and HNF3alpha. Gel-shift analyses showed that HNF3, NF1/CTF, and Sp1-like sites specifically recognized nuclear factors. Super-shift experiments indicated that HNF3beta was the major form of HNF3 interacting with the HNF3/NF1 site. The well-differentiated hepatoma cell line mhATFS315 transfected with a truncated form of HNF3beta, which competitively blocks HNF3 transactivating activity, expressed the Col18a1gene at a very low level. Taken together, these data strongly suggest that Col18a1 is a liver-specific gene. Furthermore, gel-shift analyses performed with nuclear factors prepared from well-differentiated hepatocellular carcinomas showed increased HNF3/NF1 binding activity compared with normal livers. Consequently, the precursor of endostatin might be differently expressed according to the differentiated and/or transformed state of hepatocytes.

Type XVIII collagen is a recently discovered nonfibrillar collagen associated with basement membranes in mice and expressed at high levels in human liver. We studied the origin, distribution, and RNA levels of type XVIII collagen in normal and fibrotic human livers by in situ hybridization, immunohistochemistry, and Northern and dot blots and compared procollagen alpha1(XVIII) RNA levels with those of procollagen alpha1(IV) and laminin gamma1, the two major components of liver basement membranes. In normal liver, type XVIII collagen was heavily deposited in perisinusoidal spaces and basement membrane zones. The major source of type XVIII collagen was hepatocytes and, to a lesser extent, endothelial, biliary epithelial, and vascular smooth muscle cells and peripheral nerves. In cirrhosis, type XVIII collagen formed a thick deposit along capillarized sinusoids. Grain counts after in situ hybridization showed myofibroblasts to increase their expression 13-fold in active and twofold in quiescent fibrosis, whereas hepatocytes increased their expression only twofold in both active and quiescent fibrosis. Activated stellate cells in vitro expressed type XVIII collagen at high levels. These data indicate that type XVIII collagen is a component of the perisinusoidal space and is associated with basement membrane remodeling. Hepatocytes and activated stellate cells are important sources of type XVIII collagen in normal and fibrotic liver respectively, which suggests tissue-specific regulation of its expression.