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1.  Stem Cells From Umbilical Cord Wharton’s Jelly From Preterm Birth Have Neuroglial Differentiation Potential 
Reproductive Sciences  2013;20(12):1455-1464.
The aim of the study is to determine the neuroglial differentiation potential of human Wharton’s jelly-derived mesenchymal stem cells (WJ-MSCs) from preterm birth when compared to term delivery.
Study Design:
The WJ-MSCs from umbilical cords of preterm birth and term controls were isolated and induced into neural progenitors. The cells were analyzed for neuroglial markers by flow cytometry, real-time polymerase chain reaction, and immunocytochemistry.
Independent of gestational age, a subset of WJ-MSC displayed the neural progenitor cell markers Nestin and Musashi-1 and the mature neural markers microtubule-associated protein 2, glial fibrillary acidic protein, and myelin basic protein. Neuroglial induction of WJ-MSCs from term and preterm birth resulted in the enhanced transcription of Nestin and Musashi-1.
Undifferentiated WJ-MSCs from preterm birth express neuroglial markers and can be successfully induced into neural progenitors similar to term controls. Their potential use as cellular graft in neuroregenerative therapy for peripartum brain injury in preterm birth has to be tested.
PMCID: PMC3817666  PMID: 23670950
mesenchymal stem cells; neuroglial differentiation; neuroregeneration; prematurity; Wharton’s jelly
2.  The H19/let-7 double-negative feedback loop contributes to glucose metabolism in muscle cells 
Nucleic Acids Research  2014;42(22):13799-13811.
The H19 lncRNA has been implicated in development and growth control and is associated with human genetic disorders and cancer. Acting as a molecular sponge, H19 inhibits microRNA (miRNA) let-7. Here we report that H19 is significantly decreased in muscle of human subjects with type-2 diabetes and insulin resistant rodents. This decrease leads to increased bioavailability of let-7, causing diminished expression of let-7 targets, which is recapitulated in vitro where H19 depletion results in impaired insulin signaling and decreased glucose uptake. Furthermore, acute hyperinsulinemia downregulates H19, a phenomenon that occurs through PI3K/AKT-dependent phosphorylation of the miRNA processing factor KSRP, which promotes biogenesis of let-7 and its mediated H19 destabilization. Our results reveal a previously undescribed double-negative feedback loop between sponge lncRNA and target miRNA that contributes to glucose regulation in muscle cells.
PMCID: PMC4267628  PMID: 25399420
3.  Optical Flow Estimation for Flame Detection in Videos 
Computational vision-based flame detection has drawn significant attention in the past decade with camera surveillance systems becoming ubiquitous. Whereas many discriminating features, such as color, shape, texture, etc., have been employed in the literature, this paper proposes a set of motion features based on motion estimators. The key idea consists of exploiting the difference between the turbulent, fast, fire motion, and the structured, rigid motion of other objects. Since classical optical flow methods do not model the characteristics of fire motion (e.g., non-smoothness of motion, non-constancy of intensity), two optical flow methods are specifically designed for the fire detection task: optimal mass transport models fire with dynamic texture, while a data-driven optical flow scheme models saturated flames. Then, characteristic features related to the flow magnitudes and directions are computed from the flow fields to discriminate between fire and non-fire motion. The proposed features are tested on a large video database to demonstrate their practical usefulness. Moreover, a novel evaluation method is proposed by fire simulations that allow for a controlled environment to analyze parameter influences, such as flame saturation, spatial resolution, frame rate, and random noise.
PMCID: PMC4000537  PMID: 23613042
Fire detection; optical flow; optimal mass transport; video analytics
4.  Piriformospora indica Root Colonization Triggers Local and Systemic Root Responses and Inhibits Secondary Colonization of Distal Roots 
PLoS ONE  2013;8(7):e69352.
Piriformosporaindica is a basidiomycete fungus colonizing roots of a wide range of higher plants, including crop plants and the model plant Arabidopsis thaliana. Previous studies have shown that P. indica improves growth, and enhances systemic pathogen resistance in leaves of host plants. To investigate systemic effects within the root system, we established a hydroponic split-root cultivation system for Arabidopsis. Using quantitative real-time PCR, we show that initial P. indica colonization triggers a local, transient response of several defense-related transcripts, of which some were also induced in shoots and in distal, non-colonized roots of the same plant. Systemic effects on distal roots included the inhibition of secondary P. indica colonization. Faster and stronger induction of defense-related transcripts during secondary inoculation revealed that a P. indica pretreatment triggers root-wide priming of defense responses, which could cause the observed reduction of secondary colonization levels. Secondary P. indica colonization also induced defense responses in distant, already colonized parts of the root. Endophytic fungi therefore trigger a spatially specific response in directly colonized and in systemic root tissues of host plants.
PMCID: PMC3724858  PMID: 23922705
5.  Non-Invasive Continuous Glucose Monitoring with Multi-Sensor Systems: A Monte Carlo-Based Methodology for Assessing Calibration Robustness 
Sensors (Basel, Switzerland)  2013;13(6):7279-7295.
In diabetes research, non-invasive continuous glucose monitoring (NI-CGM) devices represent a new and appealing frontier. In the last years, some multi-sensor devices for NI-CGM have been proposed, which exploit several sensors measuring phenomena of different nature, not only for measuring glucose related signals, but also signals reflecting some possible perturbing processes (temperature, blood perfusion). Estimation of glucose levels is then obtained combining these signals through a mathematical model which requires an initial calibration step exploiting one reference blood glucose (RBG) sample. Even if promising results have been obtained, especially in hospitalized volunteers, at present the temporal accuracy of NI-CGM sensors may suffer because of environmental and physiological interferences. The aim of this work is to develop a general methodology, based on Monte Carlo (MC) simulation, to assess the robustness of the calibration step used by NI-CGM devices against these disturbances. The proposed methodology is illustrated considering two examples: the first concerns the possible detrimental influence of sweat events, while the second deals with calibration scheduling. For implementing both examples, 45 datasets collected by the Solianis Multisensor system are considered. In the first example, the MC methodology suggests that no further calibration adjustments are needed after the occurrence of sweat events, because the “Multisensor+model” system is able to deal with the disturbance. The second case study shows how to identify the best time interval to update the model's calibration for improving the accuracy of the estimated glucose. The methodology proposed in this work is of general applicability and can be helpful in making those incremental steps in NI-CGM devices development needed to further improve their performance.
PMCID: PMC3715227  PMID: 23736850
diabetes; model; multisensor
6.  TGA transcription factors and jasmonate-independent COI1 signalling regulate specific plant responses to reactive oxylipins 
Journal of Experimental Botany  2013;64(4):963-975.
Jasmonates and phytoprostanes are oxylipins that regulate stress responses and diverse physiological and developmental processes. 12-Oxo-phytodienoic acid (OPDA) and phytoprostanes are structurally related electrophilic cyclopentenones, which activate similar gene expression profiles that are for the most part different from the action of the cyclopentanone jasmonic acid (JA) and its biologically active amino acid conjugates. Whereas JA–isoleucine signals through binding to COI1, the bZIP transcription factors TGA2, TGA5, and TGA6 are involved in regulation of gene expression in response to phytoprostanes. Here root growth inhibition and target gene expression were compared after treatment with JA, OPDA, or phytoprostanes in mutants of the COI1/MYC2 pathway and in different TGA factor mutants. Inhibition of root growth by phytoprostanes was dependent on COI1 but independent of jasmonate biosynthesis. In contrast, phytoprostane-responsive gene expression was strongly dependent on TGA2, TGA5, and TGA6, but not dependent on COI1, MYC2, TGA1, and TGA4. Different mutant and overexpressing lines were used to determine individual contributions of TGA factors to cyclopentenone-responsive gene expression. Whereas OPDA-induced expression of the cytochrome P450 gene CYP81D11 was primarily regulated by TGA2 and TGA5, the glutathione S-transferase gene GST25 and the OPDA reductase gene OPR1 were regulated by TGA5 and TGA6, but less so by TGA2. These results support the model that phytoprostanes and OPDA regulate differently (i) growth responses, which are COI1 dependent but jasmonate independent; and (ii) lipid stress responses, which are strongly dependent on TGA2, TGA5, and TGA6. Identification of molecular components in cyclopentenone signalling provides an insight into novel oxylipin signal transduction pathways.
PMCID: PMC3580818  PMID: 23349138
Arabidopsis thaliana; biotic and abiotic stress; class II TGA factors; detoxification; lipid signaling; reactive electrophile oxylipins.
7.  Sam50 Functions in Mitochondrial Intermembrane Space Bridging and Biogenesis of Respiratory Complexes 
Molecular and Cellular Biology  2012;32(6):1173-1188.
Mitochondria possess an outer membrane (OMM) and an inner membrane (IMM), which folds into invaginations called cristae. Lipid composition, membrane potential, and proteins in the IMM influence organization of cristae. Here we show an essential role of the OMM protein Sam50 in the maintenance of the structure of cristae. Sam50 is a part of the sorting and assembly machinery (SAM) necessary for the assembly of β-barrel proteins in the OMM. We provide evidence that the SAM components exist in a large protein complex together with the IMM proteins mitofilin and CHCHD3, which we term the mitochondrial intermembrane space bridging (MIB) complex. Interactions between OMM and IMM components of the MIB complex are crucial for the preservation of cristae. After destabilization of the MIB complex, we observed deficiency in the assembly of respiratory chain complexes. Long-term depletion of Sam50 influences the amounts of proteins from all large respiratory complexes that contain mitochondrially encoded subunits, pointing to a connection between the structural integrity of cristae, assembly of respiratory complexes, and/or the maintenance of mitochondrial DNA (mtDNA).
PMCID: PMC3295012  PMID: 22252321
8.  Membrane Abscission: First Glimpse at Dynamic ESCRTs 
Current Biology  2012;22(15):R603-R605.
Advanced live-cell imaging of the endosomal sorting complexes required for transport (ESCRT) and computational modeling have provided insights into the Vps4-dependent dynamic rearrangements of ESCRT-III filaments during membrane constriction and abscission.
PMCID: PMC3414845  PMID: 22877781
9.  Identification of aspects of functioning, disability and health relevant to patients experiencing vertigo: a qualitative study using the international classification of functioning, disability and health 
Aims of this study were to identify aspects of functioning and health relevant to patients with vertigo expressed by ICF categories and to explore the potential of the ICF to describe the patient perspective in vertigo.
We conducted a series of qualitative semi-structured face-to-face interviews using a descriptive approach. Data was analyzed using the meaning condensation procedure and then linked to categories of the International Classification of Functioning, Disability and Health (ICF).
From May to July 2010 12 interviews were carried out until saturation was reached. Four hundred and seventy-one single concepts were extracted which were linked to 142 different ICF categories. 40 of those belonged to the component body functions, 62 to the component activity and participation, and 40 to the component environmental factors. Besides the most prominent aspect “dizziness” most participants reported problems within “Emotional functions (b152), problems related to mobility and carrying out the daily routine. Almost all participants reported “Immediate family (e310)” as a relevant modifying environmental factor.
From the patients’ perspective, vertigo has impact on multifaceted aspects of functioning and disability, mainly body functions and activities and participation. Modifying contextual factors have to be taken into account to cover the complex interaction between the health condition of vertigo on the individuals’ daily life. The results of this study will contribute to developing standards for the measurement of functioning, disability and health relevant for patients suffering from vertigo.
PMCID: PMC3464694  PMID: 22738067
Vertigo (MeSH); Outcome assessment (Health Care) (MeSH); Qualitative research (MeSH); Classification (MeSH)
10.  Data Processing for Noninvasive Continuous Glucose Monitoring with a Multisensor Device 
Impedance spectroscopy has been shown to be a candidate for noninvasive continuous glucose monitoring in humans. However, in addition to glucose, other factors also have effects on impedance characteristics of the skin and underlying tissue.
Impedance spectra were summarized through a principal component analysis and relevant variables were identified with Akaike's information criterion. In order to model blood glucose, a linear least-squares model was used. A Monte Carlo simulation was applied to examine the effects of personalizing models.
The principal component analysis was able to identify two major effects in the impedance spectra: a blood glucose-related process and an equilibration process related to moisturization of the skin and underlying tissue. With a global linear least-squares model, a coefficient of determination (R2) of 0.60 was achieved, whereas the personalized model reached an R2 of 0.71. The Monte Carlo simulation proved a significant advantage of personalized models over global models.
A principal component analysis is useful for extracting glucose-related effects in the impedance spectra of human skin. A linear global model based on Solianis Multisensor data yields a good predictive power for blood glucose estimation. However, a personalized linear model still has greater predictive power.
PMCID: PMC3192636  PMID: 21722585
basis functions; dielectric characterization; functional data analysis; multiple regression; personal calibration; variable selection
11.  Visualization of wounding-induced root-to-shoot communication in Arabidopsis 
Plant Signaling & Behavior  2011;6(7):1037-1039.
It is known that wounding systemically activates the expression of various defense-related genes in plants. However, most studies of wound-induced systemic response are concerned with a leaf-to-leaf response. We have recently reported that the long distance signaling was also observed in the shoots of Arabidopsis seedling with wounded roots. We identified early and late root-to-shoot responsive (RtS) genes that were upregulated in the shoots of root-wounded seedlings at 30 min and 6 h post-injury, respectively. It is likely that the primary signals were rapidly transfered from injured roots to shoots, and then these signals were converted into chemical signals. In fact, increase of JA and OPDA content activated the expression of early and late RtS genes in shoots, respectively. In addition, we visualized wound-induced root-to-shoot response by using RtS pro-moter-luciferase (Luc) transgenic plants. Analysis of the AtERF13 promoter::Luc transgenic plants clearly shows that the wound-induced root-to-shoot signaling was rapidly activated via the vascular systems.
PMCID: PMC3257789  PMID: 21617378
wounding; root-to-shoot; inter-organ communication; long distance signaling; oxylipin; microarray
12.  Patients' functioning as predictor of nursing workload in acute hospital units providing rehabilitation care: a multi-centre cohort study 
Management decisions regarding quality and quantity of nurse staffing have important consequences for hospital budgets. Furthermore, these management decisions must address the nursing care requirements of the particular patients within an organizational unit. In order to determine optimal nurse staffing needs, the extent of nursing workload must first be known. Nursing workload is largely a function of the composite of the patients' individual health status, particularly with respect to functioning status, individual need for nursing care, and severity of symptoms. The International Classification of Functioning, Disability and Health (ICF) and the derived subsets, the so-called ICF Core Sets, are a standardized approach to describe patients' functioning status. The objectives of this study were to (1) examine the association between patients' functioning, as encoded by categories of the Acute ICF Core Sets, and nursing workload in patients in the acute care situation, (2) compare the variance in nursing workload explained by the ICF Core Set categories and with the Barthel Index, and (3) validate the Acute ICF Core Sets by their ability to predict nursing workload.
Patients' functioning at admission was assessed using the respective Acute ICF Core Set and the Barthel Index, whereas nursing workload data was collected using an established instrument. Associations between dependent and independent variables were modelled using linear regression. Variable selection was carried out using penalized regression.
In patients with neurological and cardiopulmonary conditions, selected ICF categories and the Barthel Index Score explained the same variance in nursing workload (44% in neurological conditions, 35% in cardiopulmonary conditions), whereas ICF was slightly superior to Barthel Index Score for musculoskeletal conditions (20% versus 16%).
A substantial fraction of the variance in nursing workload in patients with rehabilitation needs in the acute hospital could be predicted by selected categories of the Acute ICF Core Sets, or by the Barthel Index score. Incorporating ICF Core Set-based data in nursing management decisions, particularly staffing decisions, may be beneficial.
PMCID: PMC2988780  PMID: 21034438
13.  Functioning and health in patients with cancer on home-parenteral nutrition: a qualitative study 
Malnutrition is a common problem in patients with cancer. One possible strategy to prevent malnutrition and further deterioration is to administer home-parenteral nutrition (HPN). While the effect on survival is still not clear, HPN presumably improves functioning and quality of life. Thus, patients' experiences concerning functioning and quality of life need to be considered when deciding on the provision of HPN. Currently used quality of life measures hardly reflect patients' perspectives and experiences. The objective of our study was to investigate the perspectives of patients with cancer on their experience of functioning and health in relation to HPN in order to get an item pool to develop a comprehensive measure to assess the impact of HPN in this population.
We conducted a series of qualitative semi-structured interviews. The interviews were analysed to identify categories of the International Classification of Functioning, Disability and Health (ICF) addressed by patients' statements. Patients were consecutively included in the study until an additional patient did not yield any new information.
We extracted 94 different ICF-categories from 16 interviews representing patient-relevant aspects of functioning and health (32 categories from the ICF component 'Body Functions', 10 from 'Body Structures', 32 from 'Activities & Participation', 18 from 'Environmental Factors'). About 8% of the concepts derived from the interviews could not be linked to specific ICF categories because they were either too general, disease-specific or pertained to 'Personal Factors'. Patients referred to 22 different aspects of functioning improving due to HPN; mainly activities of daily living, mobility, sleep and emotional functions.
The ICF proved to be a satisfactory framework to standardize the response of patients with cancer on HPN. For most aspects reported by the patients, a matching concept and ICF category could be found. The development of categories of the component 'Personal Factors' should be promoted to close the existing gap when analyzing interviews using the ICF. The identification and standardization of concepts derived from individual interviews was the first step towards creating new measures based on patients' preferences and experiences which both catch the most relevant aspects of functioning and are sensitive enough to monitor change associated to an intervention such as HPN in a vulnerable population with cancer.
PMCID: PMC2862019  PMID: 20398396
14.  Pollen allergens do not come alone: pollen associated lipid mediators (PALMS) shift the human immue systems towards a TH2-dominated response 
Pollen allergy is characterized by a TH2-biased immune response to pollen-derived allergens. However, pollen-exposed epithelia do not encounter pure allergen but rather a plethora of protein and non-protein substances. We demonstrated that pollen liberate lipids with chemical and functional similarities to leukotriens and prostaglandins - the pollen associated lipid mediators (PALMs). To date, two main groups of PALMs have been characterized: The immunostimulatory PALMs activating innate immune cells such as neutrophils and eosinophils, and the immunomodulatory E1-phytoprostanes blocking IL-12 production of dendritic cells, resulting in the preferential induction of TH2 responses. This article reviews our work in the field of PALMs and their effects on cells of the innate and adoptive immune system. From recent results a general picture starts to emerge in which PALMs (and possibly other pollen-associated substances) may - independently from protein allergens - propagate an overall TH2 favoring micromilieu in pollen exposed tissue of predisposed individuals.
PMCID: PMC2776232  PMID: 19946407
15.  Jasmonic acid-induced volatiles of Brassica oleracea attract parasitoids: effects of time and dose, and comparison with induction by herbivores 
Journal of Experimental Botany  2009;60(9):2575-2587.
Caterpillar feeding induces direct and indirect defences in brassicaceous plants. This study focused on the role of the octadecanoid pathway in induced indirect defence in Brassica oleracea. The effect of induction by exogenous application of jasmonic acid (JA) on the responses of Brussels sprouts plants and on host-location behaviour of associated parasitoid wasps was studied. Feeding by the biting–chewing herbivores Pieris rapae and Plutella xylostella resulted in significantly increased endogenous levels of JA, a central component in the octadecanoid signalling pathway that mediates induced plant defence. The levels of the intermediate 12-oxophyto-dienoic acid (OPDA) were significantly induced only after P. rapae feeding. Three species of parasitoid wasps, Cotesia glomerata, C. rubecula, and Diadegma semiclausum, differing in host range and host specificity, were tested for their behavioural responses to volatiles from herbivore-induced, JA-induced, and non-induced plants. All three species were attracted to volatiles from JA-induced plants compared with control plants; however, they preferred volatiles from herbivore-induced plants over volatiles from JA-induced plants. Attraction of C. glomerata depended on both timing and dose of JA application. JA-induced plants produced larger quantities of volatiles than herbivore-induced and control plants, indicating that not only quantity, but also quality of the volatile blend is important in the host-location behaviour of the wasps.
PMCID: PMC2692006  PMID: 19451186
Brussels sprouts; cabbage; induced indirect defence; jasmonate; parasitoid host-location behaviour; octadecanoid pathway; oxylipin; volatile emission
16.  Identification of ICF categories relevant for nursing in the situation of acute and early post-acute rehabilitation 
BMC Nursing  2008;7:3.
The recovery of patients after an acute episode of illness or injury depends both on adequate medical treatment and on the early identification of needs for rehabilitation care. The process of early beginning rehabilitation requires efficient communication both between health professionals and the patient in order to effectively address all rehabilitation goals. The currently used nursing taxonomies, however, are not intended for interdisciplinary use and thus may not contribute to efficient rehabilitation management and an optimal patient outcome. The ICF might be the missing link in this communication process. The objective of this study was to identify the categories of the International Classification of Functioning, Disability and Health (ICF) categories relevant for nursing care in the situation of acute and early post-acute rehabilitation.
First, in a consensus process, "Leistungserfassung in der Pflege" (LEP) nursing interventions relevant for the situation of acute and early post-acute rehabilitation were selected. Second, in an integrated two-step linking process, two nursing experts derived goals of LEP nursing interventions from their practical knowledge and selected corresponding ICF categories most relevant for patients in acute and post-acute rehabilitation (ICF Core Sets).
Eighty-seven percent of ICF Core Set categories could be linked to goals of at least one nursing intervention variable of LEP. The ICF categories most frequently linked with LEP nursing interventions were respiration functions, experience of self and time functions and focusing attention. Thirteen percent of ICF Core Set categories could not be linked with LEP nursing interventions. The LEP nursing interventions which were linked with the highest number of different ICF-categories of all were "therapeutic intervention", "patient-nurse communication/information giving" and "mobilising".
The ICF Core Sets for the acute hospital and early post-acute rehabilitation facilities are highly relevant for rehabilitation nursing. Linking nursing interventions with ICF Core Set categories is a feasible way to analyse nursing. Using the ICF Core Sets to describe goals of nursing interventions both facilitates inter-professional communication and respects patient's needs. The ICF may thus be a useful framework to set nursing intervention goals.
PMCID: PMC2276191  PMID: 18282288
17.  Nutritional upgrading for omnivorous carpenter ants by the endosymbiont Blochmannia 
BMC Biology  2007;5:48.
Carpenter ants (genus Camponotus) are considered to be omnivores. Nonetheless, the genome sequence of Blochmannia floridanus, the obligate intracellular endosymbiont of Camponotus floridanus, suggests a function in nutritional upgrading of host resources by the bacterium. Thus, the strongly reduced genome of the endosymbiont retains genes for all subunits of a functional urease, as well as those for biosynthetic pathways for all but one (arginine) of the amino acids essential to the host.
Nutritional upgrading by Blochmannia was tested in 90-day feeding experiments with brood-raising in worker-groups on chemically defined diets with and without essential amino acids and treated or not with antibiotics. Control groups were fed with cockroaches, honey water and Bhatkar agar. Worker-groups were provided with brood collected from the queenright mother-colonies (45 eggs and 45 first instar larvae each). Brood production did not differ significantly between groups of symbiotic workers on diets with and without essential amino acids. However, aposymbiotic worker groups raised significantly less brood on a diet lacking essential amino acids. Reduced brood production by aposymbiotic workers was compensated when those groups were provided with essential amino acids in their diet. Decrease of endosymbionts due to treatment with antibiotic was monitored by qRT-PCR and FISH after the 90-day experimental period. Urease function was confirmed by feeding experiments using 15N-labelled urea. GC-MS analysis of 15N-enrichment of free amino acids in workers revealed significant labelling of the non-essential amino acids alanine, glycine, aspartic acid, and glutamic acid, as well as of the essential amino acids methionine and phenylalanine.
Our results show that endosymbiotic Blochmannia nutritionally upgrade the diet of C. floridanus hosts to provide essential amino acids, and that it may also play a role in nitrogen recycling via its functional urease. Blochmannia may confer a significant fitness advantage via nutritional upgrading by enhancing competitive ability of Camponotus with other ant species lacking such an endosymbiont. Domestication of the endosymbiont may have facilitated the evolutionary success of the genus Camponotus.
PMCID: PMC2206011  PMID: 17971224
19.  Herpes Simplex Virus 1 Envelopment Follows Two Diverse Pathways 
Journal of Virology  2005;79(20):13047-13059.
Herpesvirus envelopment is assumed to follow an uneconomical pathway including primary envelopment at the inner nuclear membrane, de-envelopment at the outer nuclear membrane, and reenvelopment at the trans-Golgi network. In contrast to the hypothesis of de-envelopment by fusion of the primary envelope with the outer nuclear membrane, virions were demonstrated to be transported from the perinuclear space to rough endoplasmic reticulum (RER) cisternae. Here we show by high-resolution microscopy that herpes simplex virus 1 envelopment follows two diverse pathways. First, nuclear envelopment includes budding of capsids at the inner nuclear membrane into the perinuclear space whereby tegument and a thick electron dense envelope are acquired. The substance responsible for the dense envelope is speculated to enable intraluminal transportation of virions via RER into Golgi cisternae. Within Golgi cisternae, virions are packaged into transport vacuoles containing one or several virions. Second, for cytoplasmic envelopment, capsids gain direct access from the nucleus to the cytoplasm via impaired nuclear pores. Cytoplasmic capsids could bud at the outer nuclear membrane, at membranes of RER, Golgi cisternae, and large vacuoles, and at banana-shaped membranous entities that were found to continue into Golgi membranes. Envelopes originating by budding at the outer nuclear membrane and RER membrane also acquire a dense substance. Budding at Golgi stacks, designated wrapping, results in single virions within small vacuoles that contain electron-dense substances between envelope and vacuolar membranes.
PMCID: PMC1235821  PMID: 16189007
20.  Pollen-associated phytoprostanes inhibit dendritic cell interleukin-12 production and augment T helper type 2 cell polarization 
Pollen grains induce allergies in susceptible individuals by release of allergens upon contact with mucosal membranes of the upper respiratory tract. We recently demonstrated that pollen not only function as allergen carriers but also as rich sources of bioactive lipids that attract cells involved in allergic inflammation such as neutrophils and eosinophils. Here we demonstrate that soluble factors from birch (Betula alba L.) pollen activate human dendritic cells (DCs) as documented by phenotypical and functional maturation and altered cytokine production. Betula alba L. aqueous pollen extracts (Bet.-APE) selectively inhibited interleukin (IL)-12 p70 production of lipopolysaccharide (LPS)- or CD40L-activated DC, whereas IL-6, IL-10, and TNFα remained unchanged. Presence of Bet.-APE during DC activation resulted in DC with increased T helper type 2 (Th2) cell and reduced Th1 cell polarizing capacity. Chemical analysis of Bet.-APE revealed the presence of phytoprostanes (dinor isoprostanes) with prostaglandin E1-, F1-, A1-, or B1-ring systems of which only E1-phytoprostanes dose dependently inhibited the LPS-induced IL-12 p70 release and augmented the Th2 cell polarizing capacity of DC. These results suggest that pollen-derived E1-phytoprostanes not only resemble endogenous prostaglandin E2 structurally but also functionally in that they act as regulators that modulate human DC function in a fashion that favors Th2 cell polarization.
PMCID: PMC2213058  PMID: 15728240
21.  Impairment of Nuclear Pores in Bovine Herpesvirus 1-Infected MDBK Cells 
Journal of Virology  2005;79(2):1071-1083.
Herpesvirus capsids originating in the nucleus overcome the nucleocytoplasmic barrier by budding at the inner nuclear membrane. The fate of the resulting virions is still under debate. The fact that capsids approach Golgi membranes from the cytoplasmic side led to the theory of fusion between the viral envelope and the outer nuclear membrane, resulting in the release of capsids into the cytoplasm. We recently discovered a continuum from the perinuclear space to the Golgi complex implying (i) intracisternal viral transportation from the perinuclear space directly into Golgi cisternae and (ii) the existence of an alternative pathway of capsids from the nucleus to the cytoplasm. Here, we analyzed the nuclear surface by high-resolution microscopy. Confocal microscopy of MDBK cells infected with recombinant bovine herpesvirus 1 expressing green fluorescent protein fused to VP26 (a minor capsid protein) revealed distortions of the nuclear surface in the course of viral multiplication. High-resolution scanning and transmission electron microscopy proved the distortions to be related to enlargement of nuclear pores through which nuclear content including capsids protrudes into the cytoplasm, suggesting that capsids use impaired nuclear pores as gateways to gain access to the cytoplasmic matrix. Close examination of Golgi membranes, rough endoplasmic reticulum, and outer nuclear membrane yielded capsid-membrane interaction of high identity to the budding process at the inner nuclear membrane. These observations signify the ability of capsids to induce budding at any cell membrane, provided the fusion machinery is present and/or budding is not suppressed by viral proteins.
PMCID: PMC538577  PMID: 15613336

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