Alveolar type II

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Response of alveolar type II pneumocytes to mechanical stimulation

Response of alveolar type II pneumocytes to mechanical stimulation

(A) The representation of the stretch field imposed by the micro-spatula on the silastic membrane is simplified, since the stretch magnitude changes continuously and not discrete steps as shown here. The differently colored areas represent the length increase calculated by subtracting the displacement at the most far away distance from the micro-spatula (e.g. 50 µm) to the displacement at the closest distance from the micro-spatula (e.g. 30 µm) at each selected range. In the drawing, the micro-spatula is shown in blue at center top and membrane areas with different distances from the tip in yellow (10-30 µm from the tip); in green (30-50 µm) and in blue (50-70 µm). The left half of the scheme shows the horizontal displacement that the cells experience whereas the right half of the picture shows the displacement that the cells experience in the z-axis. (B) Horizontal stretch (average ± SD) shown in a histogram. The red bar represents the average stretch that cells experienced at 30-50 µm distance. (C) Two ATII cells before and after stretch. The cell membrane is highlighted by the solid lines. The dashed lines on the left panel show the outline of the cell before stretch. Abbreviation: ATII, alveolar type II.
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miRNA-154 mediates the transdifferentiation of alveolar type II to alveolar type I cells in the mouse model of Bronchopulmonary Dysplasia

miRNA-154 mediates the transdifferentiation of alveolar type II to alveolar type I cells in the mouse model of Bronchopulmonary Dysplasia

With the next step we examined the impact of inhaling high oxygen concentrations on the histologic lung structure and the genetic expression profile (see Figure 8). For this objective we exposed mice to high oxygen concentrations (85% O2) from birth (P0) until P8, harvested the lungs after a recovery period of 8 days at P16 and compared these mice to normoxic conditions (see Figure 8.A). As expected we found the alveolar structures to be interrupted in development showing an increased diameter (MLI; mean linear intercept) and thickened alveolar walls (see Figure 8.B). These findings indicate impaired alveolarization, which among others is a typical characteristic of lungs suffering from BPD (Coalson et al., 1995; Voynow, 2017). Our results are consistent with findings from other studies using a BPD animal model, which also found increased MLI and thickened alveolar walls in lungs after exposure to hyperoxia compared to control animals (Alejandre- Alcazar et al., 2007; Madurga et al., 2014; Martin et al., 2014; Niedermaier and Hilgendorff, 2015; Porzionato et al., 2016). It has been discussed that MLI and septal thickness are parameters, which might be affected during lung harvest and histological preparation and hence possibly adulterated (Porzionato et al., 2016). Indeed, the preparative procedure may affect parameters of lung architecture of individual samples, because the preparations were manually performed, meaning that a variation of handling between the individual subjects may occur. In order to eliminate this factor, we masked the mice while doing the preparation, not knowing which mouse belongs to which group of treatment. Therefore, mice belonging to different experimental groups are equally exposed to potential disturbing factors. There was no possibility to manipulate the lungs in our favor.
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Mechanisms of alveolar protein clearance in isolated rabbit lungs : role of clathrin- and caveolae-mediated endocytosis of albumin by the alveolar epithelium

Mechanisms of alveolar protein clearance in isolated rabbit lungs : role of clathrin- and caveolae-mediated endocytosis of albumin by the alveolar epithelium

The complexity of the isolated lung model makes it difficult to ascribe physiological and biochemical events to specific cell types. Thus, to further confirm our hypothesis that excess albumin was taken up by the epithelium of the distal air spaces, experiments in cultured human alveolar epithelial A549 cells were performed. This cell line is a popularly-used in vitro model of type II alveolar epithelial cells (Foster, Oster et al. 1998). The A549 cell line exhibits many characteristics of alveolar type II cells, including the existence of lamellar inclusion bodies and the ability to synthesize surfactant constituents (Lieber, Smith et al. 1976). Furthermore, A549 cells were demonstrated to take up transferrin, a maker of receptor-mediated endocytosis, as well as cationised ferritin, an unspecific marker for absorption in a temperature-, time-, and concentration-dependent manner. This cell-line was also used as a tool to investigate sodium transport studies (Lazrak, Samanta et al. 2000) because of similarities in sodium channel expression when compared with primary alveolar type II cells. However, in contrast to type II cells, A549 cells neither polarize nor form fully-developed intercellular junctions, and are therefore unable to establish electrophysiologically tight monolayers (Foster, Oster et al. 1998). Consequently, transcytosis cannot be addressed in this cell-line. Additionally, A549 cells represent only one cell type of the alveolar epithelium (type II cells, which have been accredited with a key role in transport processes) but not type I cells. Nevertheless, A549 cells represent a powerful tool to with which investigate alveolar epithelial uptake of macromolecules such as albumin.
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Effects of -carotene and its cleavage products in primary pneumocyte type II cells

Effects of -carotene and its cleavage products in primary pneumocyte type II cells

These findings indicate that β-carotene cleavage products are most likely responsible for the increased lung cancer risk observed in chemoprevention trials. However, there is a lack of information on the sensitivity of the putative target cells in the lung, namely alveolar type II cells. Alveolar type II cells have a central role in the maintenance of normal lung function, reaction to injury, and response to specific toxins. They express phase I and phase II biotransformation enzymes—particularly cytochrome P450-dependent mono-oxygenases [ 30 ]—and thus are potential targets for many inhaled materials, and at the same time represent the relevant cells for the evaluation of a mutagenic and carcinogenic potential of specific agents [ 31 ]. Therefore, the goal of this investigation was the evaluation of the cyto- and genotoxic potential of β-carotene and its cleavage products in primary rat pneumocytes. 2. Materials and Methods
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On the effective theory of type II string compactifications on nilmanifolds and coset spaces

On the effective theory of type II string compactifications on nilmanifolds and coset spaces

a tion for the four type IIB stati SU(2)-stru ture ompa ti ations on oset spa es. However, for three of these type IIB models we found a T-duality relating them to type[r]

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Hunting poses only a low risk for alveolar echinococcosis

Hunting poses only a low risk for alveolar echinococcosis

The Austrian province of Tyrol belongs to the areas where the alveolar echinococcosis (AE) caused by the fox tapeworm Echinococcus multilocularis (E. multilocularis) is highly endemic. In Central Europe and since 2011 in Austria, a growing incidence of human cases of AE has been observed, presumably linked with increasing fox populations infected by the fox tapeworm E. multilocularis. Hunting and the related activities put hunters in a high-risk group, and they are considered particularly vulnerable for the contraction of an AE. In light of this risk and the increased number of AE cases made public in Austria, the objective of the study was to investigate the prevalence of AE in hunters and to provide a possible connection to the incidence increase. In 2015 and 2016, we examined 813 serums of active hunters from all nine districts of Tyrol and serologically tested them for E. multilocularis antibodies. Twenty-one (2.58%) positive results in ELISA were detected via Western blot (WB), and only one (0.12%) serum showed a low positive reaction. No lesion in the liver parenchyma could be detected by abdominal ultrasonography in this patient so far, but the risk of developing alveolar echinococcosis remains for this WB-positive hunter. Risk factor analysis of these 813 hunters revealed that 697 (85.7%) hunted red foxes regularly and 332 (40.8%) of those skinned them as well. Three hundred and eighteen (39.1%) out of the 813 hunters were owners of hunting dogs; 89 (10.9%) and 243 (29.9%) were owners of non-hunting dogs and cats, respectively. Our results indicate that hunters do not have a greater risk of infection with E. multilocularis compared to non-hunters in Austria. The cause of the unexpected increase in AE cases in Austria remains unclear.
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Charge separation and transfer in hybrid type II tunneling structures of CdTe and CdSe nanocrystals

Charge separation and transfer in hybrid type II tunneling structures of CdTe and CdSe nanocrystals

The OD-graphs (fig. 4.2 a) have been used to determine the precise concentrations of nanocrystals in each sample. This allows for correction of the small concentration variations observed. We fitted the OD-curve of the hybrid sample with a least square fit (broken line, fig. 4.2 a) by linear superposition of both reference OD-graphs. Thus, from the fitting coefficients we obtained the relative concentration differences between hybrid and reference samples. This relative concentration variation has been applied to rescale the PL-intensities of the reference samples in fig. 4.2 b (according chapter 3.3.2). A quenching of 63 % was obtained for the CdTe567 PL-emission in the hybrid sample (fig. 4.2 b). Hence, we can conclude that the PL of CdTe567 is quenched due to charge separation induced by electron transfer from CdTe567 to CdSe529. We can assume that energy transfer (see chapter 2.3.4) from CdTe567 to CdSe529 is very unlikely due to negligible spectral overlap and especially due to the unfavorable energy gaps, the smallest energy gap being located at CdTe567. Hence, energy transfer would lead to a PL-enhancement of the CdTe567 since it is the ET-acceptors. The quenching of steady state PL therefore strongly indicates charge separation in this type II aligned closely packed nanocrystal system.
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Sulfite Induces Release of Lipid Mediators by Alveolar Macrophages 

Sulfite Induces Release of Lipid Mediators by Alveolar Macrophages 

in m ediating their effects (Denzlinger, 1996). Chronic exposure of dogs to a neutral sulfite aerosol alters the alveolar-capillary permeability as well as the lysosomal enzyme secretion as as­ sessed by determ ination of the content of protein and albumin and the extracellular activity of ß-N- acetyl-glucosaminidase in the bronchoalveolar la­ vage fluid (M aier et al., 1992). Both capillary p er­ meability and lysosomal enzyme secretion signifi­ cantly increased in the second half of the exposure period of one year. The data from the present in- vitro study suggest that PAF and LTB 4 released by
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Inhibition of Photosystem II by Ioxynil in Wild Type and Resistant Mutant of Synechocystis 6714 

Inhibition of Photosystem II by Ioxynil in Wild Type and Resistant Mutant of Synechocystis 6714 

O ur results clearly show that the inhibitions by ioxynil on the acceptor side and the donor side of PS II are related to two different sites of action. Dj is supposed to span the thylakoidal m em brane and to participate in the binding of m anganese and extrinsic polypeptides involved in oxygen evolution. Then, it would have been possible that the binding of ioxynil in the Q B niche produces a change of conform ation of Di and perturbs the donor side of PS II just as Tris treatm ent (that removes the three peripheral poly­ peptides of PS II oxygen evolution) leads to a d e­ crease in inhibitory potency of the classical inhibitors triazine, triazinone and ureas, but not of phenol, quinolone and pyridone inhibitors [1]. But the fact that in the IoxI the I50 for inhibition of the donor side is not modified com pared to the wild type whereas the I50 for electron transfer betw een Q A to Q B is ten ­ fold that of the wild type, is in favor of the existence of two distinct sites of action.
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A New-Type Photosystem II Inhibitor which Blocks Electron Transport in Water-Oxidation System 

A New-Type Photosystem II Inhibitor which Blocks Electron Transport in Water-Oxidation System 

H. Koike et al. ■ N ew -T ype Photosystem II Inhibitor Temperature P C ) Fig. 2. E ffects o f cyanoacrylate, A C m l2 and A P p l2 on therm olum inescence glow peak as com pared with those o f D C M U , atrazine and ioxynil. Sample thylakoids treated with 10 [iM each o f the inhibitors w ere illum inated with one (left colum n) or two (right colum n) flashes at —15 °C, rapidly cooled to 77 K, and then gradually warm ed in dark­ ness (0.8 °C /sec). T herm olum inescence during warming was recorded against sam ple tem perature.
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Throughput of Type II HARQ-OFDM/TDM Using MMSE-FDE in a Multipath Channel

Throughput of Type II HARQ-OFDM/TDM Using MMSE-FDE in a Multipath Channel

In this paper, the use of OFDM/TDM with MMSE-FDE and type II HARQ was presented. It was shown that, during the first uncoded transmission, the throughput can be improved using OFDM/TDM with MMSE-FDE and type II HARQ due to the frequency diversity gain and lower PAPR in comparison with conventional OFDM. The best throughput

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Novel Dinucleating Ligand Systems Containing Two Adjacent Coordination Compartments of the Potential Triamidoamine-Type -Nickel(II) and Cobalt(II) Coordination Chemistry 

Novel Dinucleating Ligand Systems Containing Two Adjacent Coordination Compartments of the Potential Triamidoamine-Type -Nickel(II) and Cobalt(II) Coordination Chemistry 

Dinuclear transition metal complexes have re­ ceived considerable attention in the past several years, mainly due to the increasing interest in co­ operative effects between individual metal cen­ ters [1, 2]. One fundamental approach to achieve this sought-after cooperativity is the design of din­ ucleating ligand matrices that hold the two metal ions in close proximity by providing adjacent coor­ dination compartments with suitable sets of donor functions [3]. In this regard we have recently studied a series of pyrazolate-based bimetallic complexes, in which the coordination spheres of the metal ions as well as the accessible range of metal-metal sep­ arations can be selectively altered by appropriate changes of the chelating substituents attached to the heterocycle [ 4 - 6 ] . Among these, the representative type I ligands H L 1 and HL 2 can be viewed as two tran-type coordination compartments [tran = tris- (aminoalkyl)amine] coupled by a pyrazole moiety (Scheme 1) [4], However, while these systems gave rise to a diverse chemistry of dinuclear complexes of (usually late) divalent 3d transition metals [ 6 ], they proved less suited for stabilizing complexes of
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SFCA-II type Ca2.46Fe3+8.57 Fe2+0.52Al5.45O24 - an improved structural model for an iron-ore sinter phase

SFCA-II type Ca2.46Fe3+8.57 Fe2+0.52Al5.45O24 - an improved structural model for an iron-ore sinter phase

, Z = 4. Structure determination and subsequent least-squares refinements resulted in a residual of R(|F|) = 0.0349 for 7406 independent reflections and 773 parameters. Site occupancy refinements on the 35 octahedral (M) and tetrahedral (T) positions in the asymmetric unit were aided by crystallochemical considerations and the assumption of charge balance between the cations and anions. The derived formula compares well with the outcome of electron microprobe studies. The crystal structure of SFCA-II shows the typical features of the SFCA-family. It can be built from an alternating sequence of two different types of fundamental layers. For SFCA-II, they are oriented parallel to (100). Layer-type I is solely based on [MO 6 ]-octahedra (M: Ca, Fe 3+ , Al) forming individual five polyhedra wide bands. Within a single band, the octahedra share common edges. Layer-type II, on the other hand, contains [MO 6 ]-octahedra as well as [TO 4 ]-tetrahedra (T: Al, Fe 3+ , Fe 2+ ). By corner sharing each [MO 6 ]-group is linked to two adjacent tetrahedra into [MT 2 O 12 ]-clusters or “winged octahedra”. Linkage between neighboring strips of these moieties is provided by additional [TO 4 ]-tetrahedra arranged in vierer single-chains. Our investigation rectifies previous studies on SFCA-II where wrong atomic coordinates have been published.
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Carnitine supplementation to obese Zucker rats prevents obesity-induced type II to type I muscle fiber transition and favors an oxidative phenotype of skeletal muscle

Carnitine supplementation to obese Zucker rats prevents obesity-induced type II to type I muscle fiber transition and favors an oxidative phenotype of skeletal muscle

In the present study we tested the hypothesis that carni- tine supplementation to obese Zucker rats counteracts the obesity-induced muscle fiber transition from type I to type II and, thereby, improves fatty acid utilization in skeletal muscle. The dietary carnitine dosage (3 g/kg diet) fed to the rats related to 156 to 216 mg/kg body weight based on an average daily feed consumption of 26 g and a body weight of 360 (initial) to 500 (final) g. This carnitine dosage is slightly higher when compared to that used in clinical studies with human subjects with different metabolic disorders in which carnitine dosages of up to 4 g/d corresponding to 60 mg/kg body weight for an individual weighing 70 kg were found to be effect- ive [28]. A key finding of the present study is that carnitine supplementation to obese rats resulted in an increased number of type I fibers and a decreased num- ber of type II fibers in rectus femoris muscle when com- pared to non-supplemented obese rats. This indicates that carnitine induces type II to type I fiber transition in femoris muscle of obese rats which was also confirmed by the finding that the type I fiber specific MYH7 mRNA level in rectus femoris muscle was markedly ele- vated in the obese carnitine group. Interestingly, the
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Early loading of plalatal implants (ortho-type II) a prospective multicenter randomized controlled clinical trial

Early loading of plalatal implants (ortho-type II) a prospective multicenter randomized controlled clinical trial

Study device The new ortho-implant type II anchor system (Orthosys- tem ® , Straumann, Basel, Switzerland; Fig.1) available with diameters of 4.1 mm and 4.8 mm, is a pure titanium 1- piece device. It consists of a endosseous implant body, a transmucosal implant neck, abutment, fixation cap and occlusal screw, all parts being made of pure titanium except the occlusal screw (stainless steal). The endosseous implant body has a self-tapping thread with a sand- blasted, large grit, acid-etched (SLA ® ) surface. A set of burs

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Early loading of plalatal implants (ortho-type II) a prospective multicenter randomized controlled clinical trial

Early loading of plalatal implants (ortho-type II) a prospective multicenter randomized controlled clinical trial

For sample size calculation an implant failure rate of 5 % for group 1 (implant loading after a post-surgical healing period of 12 weeks) an implant failure rate of 25 % for group 2 (early implant loading within 1 week post implantation) was assumed. Based on 0.8 power to detect a significant difference at the two sided 5% level with an assumed loss to follow-up of 5 %, 62 patients in each group and 124 in total will be required. Sample size calcu- lation, which based on clinical experiences with the new Orthosystem type II and early functional loading of con- ventional dental implants, was estimated with nQuery Advisor ® (Version 3.0) by the Institute of Medical Biosta- tistics, Epidemiology and Informatics (WH), University of Berlin, Germany.
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Human Alveolar Macrophages Express Elafin and Secretory Leukocyte Protease Inhibitor 

Human Alveolar Macrophages Express Elafin and Secretory Leukocyte Protease Inhibitor 

m RNA were constitutively expressed in alveolar macrophages from four different healthy subjects (Fig. 1). The identity of the amplified PCR pro­ ducts was confirmed by an independent DNA se­ quencing service (data not shown). The next series of experim ent was perform ed to determ ine if this expression is upregulated in stim ulated cells. To do so, alveolar m acrophages were exposed to either LPS (10 (ig /ml) or S. rectivirgula antigen (50 [ig/ ml) for increasing periods of time. As shown in Fig. 2, elafin m RN A expression was increased time dependently in alveolar m acrophages stimulated with S. rectivirgula antigen com pared to un­ stim ulated cells. In contrast, LPS did not signifi­ cantly upregulate elafin expression. For identical experim ental conditions, there was no evident change in the expression of SLPI (data not shown).
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Erdalkaliquadratate, II SrC40 4 * 3 H20 Typ I [1] Alkaline-Earth Squarates, II SrC40 4 -3 H 20 Type I [1] 

Erdalkaliquadratate, II SrC40 4 * 3 H20 Typ I [1] Alkaline-Earth Squarates, II SrC40 4 -3 H 20 Type I [1] 

W e iß e n b e rg a u fn a h m e n bestim m t, welche auf die tri­ kline R a u m g r u p p e P i bzw. P I hinwiesen. Intensitä­ ten w urden m it einem E n raf-N o n iu s-C A D 4 -D iffra k - to m e te r g em essen. D ab ei w urde eine Vollkugel des rezip ro k en R a u m e s bis zu 0 max = 35° ( M o K ä , G r a ­ p h itm o n o c h ro m a t o r) erfaßt. Die Position des Sr2+ ko n n te ein e r P atte rsonsynthe se en t n o m m e n werden. O- und C - A t o m e w urden in D ifferenzfouriersynthe- sen erk a n n t. D ie kristallographischen D ate n sind in de r Tab. I, die A to m p a r a m e t e r in Tab. II zu s am ­ m engefaßt. S tru k tu rfak to rta b ellen w urden beim
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The autophagic marker p62 highlights Alzheimer type II astrocytes in metabolic/hepatic encephalopathy

The autophagic marker p62 highlights Alzheimer type II astrocytes in metabolic/hepatic encephalopathy

Nuclear p62 staining was detected in enlarged glial cells of the gray matter that were consistent with AA II on HE- stained sections (Fig. 1J–L). This immunopositivity was observed in all cases with hepatic encephalopathy of dif- ferent etiologies, except for some of septic origin. Nuclear staining for p62 in AA II was particularly intense in a case

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Aspherical, Nanostructured Microparticles For Pulmonary Gene Delivery To Alveolar Macrophages

Aspherical, Nanostructured Microparticles For Pulmonary Gene Delivery To Alveolar Macrophages

In chapter IV the presented microrod system was successfully shown to be cargo loaded with the plasmid pCMV-luc in order to evaluate the proficiency of the carrier to introduce external DNA into the nuclear core of a target cell line. According to the pulmonary application purpose, aerodynamic properties were determined showing the microparticles to be qualified to reach the deep lung and therefore the site of action. The following chapter is dedicated to the consecutive steps after deposition within a biological environment. In a first step the engulfment by phagocytes had to be shown, which is a crucial and rate limiting step for the intended cargo delivery. For cell culture studies the alveolar macrophage cell line MH-S was chosen, originally isolated from bronchoalveolar lavage of BALB/c mice showing adherent behavior and typical macrophage morphology. [1] For the coating design the introduced transfection agents DEAE-D, CHT and bPEI were discussed prior to transfection experiments. Up to this point, the cargo release from bPEI microrod systems was not clarified. Whereas no release was shown within a simplified enzyme assay setup, literature showed similar systems to work efficiently under in vitro conditions. [2-4] Furthermore, bPEI shows superior transfection efficiencies compared to other compounds throughout a very large number of publications, which is in particular interesting as macrophages are known as hard to transfect. [5-7] DEAE-D and CHT could possibly lack the sufficient protection of the plasmid
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