bluuebunny/crossref_metadata_2025 huggingface dataset:
Human Multipotent Mesenchymal Stromal Cells from Fetal Lung Expressing Pluripotent Markers and Differentiating into Cell Types of Three Germ Layers
Authors: Zheng Cuiling , Yang Shaoguang , Guo Zhenxing , Liao Wenbin , Zhang Lei , Yang Renchi , Han Zhong Chao
Published: January 2010

Multipotent mesenchymal stromal cells (MSCs) are a promising cell type for cell transplantation; however, their utilization remains limited until the availability of adequate alternative sources of MSCs and the thorough understanding of the biology of MSCs isolated from various sources are realized. Fetal lung has been identified as a rich source of MSCs. To explore the therapeutic potential of passaged fetal lung MSCs (FLMSCs), the present study evaluated their growth kinetics, telomere length, karyotype, immunophenotype, and the differentiation potential during in vitro expansion. FLMSCs could be easily amplified in vitro with no significant shorting of telomere length and had a normal karyotype. No significant differences between passage 5 or passage 25 were observed in the immunophenotype analysis using flow cytometry. Moreover, flow cytometry results provided the first demonstration, to our knowledge, that FLMSCs stably expressed pluripotent markers including Oct4, Nanog, Sox2, TRA-1-60, c-Myc, and SSEA-4 through 25 passages. In vitro differentiation studies as identified by confocal microscopy, flow cytometry, RT-PCR, and immunohistochemistry showed that FLMSCs had extended capacity of differentiating into mesodermal, ectodermal, and endodermal lineages, and that their potential for adipogenic, osteogenic, and chondrogenic differentiation may be maintained over 25 passages. Furthermore, osteogenic and chondrogenic differentiation was used as an indicator of their differentiation capability in vivo, as evidenced by ectopic bone and cartilage formation. In summary, these results suggest that FLMSCs are a primitive population and that their extensive in vitro expansion does not involve significant functional modification of the cells, including morphology, growth, karyotype, immunophenotype, and mesodermal differentiation potential. Hence, FLMSCs might constitute an attractive cell resource for cell transplantation to induce regeneration of damaged tissues/organs.
Deleterious Effect of Human Umbilical Cord Blood Mononuclear Cell Transplantation on Thioacetamide-Induced Chronic Liver Damage in Rats
Authors: Álvarez-Mercado Ana I. , García-Mediavilla María V. , Sánchez-Campos Sonia , Abadía Francisco , Sáez-Lara María J. , Cabello-Donayre María , Gil Ángel , González-Gallego Javier , Fontana Luis
Published: January 2010

Our research group investigates whether human mononuclear cells isolated from umbilical cord blood (HUCBM cells) might be valuable in hepatic regenerative medicine. We recently demonstrated that HUCBM cell transplantation improves histological alterations and function of the liver in rats with acute liver damage induced by D-galactosamine. In the present study, HUCBM cells were transplanted into rats with thioacetamide (TAA)-induced liver cirrhosis, an experimental model that generates an intense fibrosis and mimics the histological and biochemical alterations found in the human disease. HUCBM transplantation had no effect on hepatic histology of cirrhotic animals. In contrast, analysis of plasma albumin and total bilirubin, liver damage markers, revealed a harmful effect of HUCBM cell transplantation in our experimental model of liver cirrhosis. Significantly higher plasma urea concentrations, marker of renal function, were observed in the cirrhotic and control rats intraportally injected with HUCBM cells than in those not receiving this therapy. Histological study revealed tubular and glomerular lesions in kidneys of cirrhotic animals transplanted with HUCBM cells. The glomeruli appeared ischemic, and the tubules showed a severe involvement that included peripheral asymmetric vacuolization and disappearance of the tubular lumen. Taken together, the histological and biochemical data suggest that the cirrhotic rats subjected to HUCBM cell therapy developed a hepatorenal syndrome.
Transient Recovery in a Rat Model of Familial Amyotrophic Lateral Sclerosis after Transplantation of Motor Neurons Derived from Mouse Embryonic Stem Cells
Authors: López-González Rodrigo , Kunckles Philip , Velasco Iván
Published: January 2010

Embryonic stem (ES) cells can be induced to differentiate into motor neurons (MN). Animal models resembling MN degeneration and paralysis observed in familial amyotrophic lateral sclerosis (ALS) have been previously reported. In this work, we aimed to investigate whether transplanted MN could prevent motor deterioration in transgenic rats expressing a mutant form of human superoxide dismutase 1 (hSOD1G93A) associated with inherited ALS. Mouse ES cells were differentiated to neurons that express green fluorescent protein (GFP) under the promoter of the MN-specific gene hb9, as well as molecular markers indicative of MN identity. Cells were grafted into the lumbar spinal cord of adult wild-type (WT) or hSOD1G93A rats at 10 weeks of age, when transgenic animals are presymptomatic. Grafted cells with MN phenotype can survive for at least 1 week in hSOD1G93A animals. To quantitatively evaluate motor performance of WT and transgenic rats, we carried out weekly rotarod tests starting when the animals were 14 weeks old. Sham and grafted WT animals showed no decline in their ability to sustain themselves on the rotating rod. In contrast, sham hSOD1G93A rats decreased in motor performance from week 16 onwards, reaching paralysis by week 19 of age. In grafted transgenic animals, there was a significant improvement in rotarod competence at weeks 16 and 17 when compared to sham hSOD1G93A. However, in the following weeks, transplanted hSOD1G93A rats showed motor deterioration and eventually exhibited paralysis by week 19. At end-stage, we found only a few endogenous MN in sham and grafted hSOD1G93A rats by cresyl violet staining; no choline acetyl transferase-positive nor GFP-positive MN were present in grafted transgenic subjects. In contrast, WT rats analyzed at the same age possessed grafted GFP-positive MN in their spinal cords. These results strongly suggest that the transgenic hSOD1G93A environment is detrimental to grafted MN in the long term.
Local Delivery of Autologous Platelet in Collagen Matrix Simulated in Situ Articular Cartilage Repair
Authors: Qi Yi Ying , Chen Xiao , Jiang Yang Zi , Cai Hong Xin , Wang Lin Lin , Song Xing Hui , Zou Xiao Hui , Ouyang Hong Wei
Published: January 2010

Bone marrow released by microfracture or full-thickness cartilage defect can initiate the in situ cartilage repair. However, it can only repair small cartilage defects (<2 cm2). This study aimed to investigate whether autologous platelet-rich plasma (PRP) transplantation in collagen matrix can improve the in situ bone marrow-initiated cartilage repair. Full-thickness cartilage defects (diameter 4 mm, thickness 3 mm) in the patellar grooves of male New Zealand White rabbits were chosen as a model of in situ cartilage repair. They were treated with bilayer collagen scaffold (group II), PRP and bilayer collagen scaffold (group III), and untreated (group I), respectively ( n = 11). The rabbits were sacrificed at 6 and 12 weeks after operation. The repaired tissues were processed for histology and for mechanical test. The results showed that at both 6 and 12 weeks, group III had the largest amounts of cartilage tissue, which restored a larger surface area of the cartilage defects. Moreover, group III had higher histological scores and more glycosaminoglycans (GAGs) content than those in the other two groups ( p < 0.05). The Young's modulus of the repaired tissue in group II and group III was higher than that of group I ( p < 0.05). Autologous PRP and bilayer collagen matrix stimulated the formation of cartilage tissues. The findings implicated that the combination of PRP with collagen matrix may repair larger cartilage defects that currently require complex autologous chondrocyte implantation (ACI) or osteochondral grafting.
Cellular Epigenetic Modifications of Neural Stem Cell Differentiation
Authors: Singh Rabindra P. , Shiue Kevin , Schomberg Dominic , Zhou Feng C.
Published: January 2010

Emerging information indicates that epigenetic modification (i.e., histone code and DNA methylation) may be integral to the maintenance and differentiation of neural stem cells (NSCs), but their actual involvement has not yet been illustrated. In this study, we demonstrated the dynamic nature of epigenetic marks during the differentiation of quiescent adult rat NSCs in neurospheres. A subpopulation of OCT4+ NSCs in the neurosphere contained histone marks, trimethylated histone 3 on lysine 27 (3me-H3K27), 2me-H3K4, and acetylated H4 (Ac-H4). A major decrease of these marks was found prior to or during differentiation, and was further diminished or reprogrammed in diverse subpopulations of migrated NSCs expressing nestin or β-III-tubulin. The DNA methylation mark 5-methyl-cytosine (5-MeC), and DNA methyltransferase (DNMT) 1 and 3a expression also correlated to the state of differentiation; they were highly present in undifferentiated NSCs but downregulated in migrated populations. In contrast, DNA methyl-CpG-binding protein (MBD1) was low in undifferentiated NSCs in neurospheres, but highly appeared in differentiating NSCs. Furthermore, we found an outward translocation of DNA methylation marker 5-MeC, DNMT1, DNMT3a, and MBD1 in NSCs as differentiation began and proceeded; 5-MeC from homogeneous nucleus to peripheral nucleus, and DMNT1a and 3a from nuclear to cytoplasm, indicating chromatin remodeling. Treatment with DNA methylation inhibitor, 5-aza-cytidine, altered DNA methylation and disrupted migration as indicated by a reduction of migrated neurons and differentiation. These results indicate that chromatin is dynamically remodeled when NSCs transform from the quiescent state to active growth, and that DNA methylation modification is essential for neural stem cell differentiation.
Antiapoptotic Effect of Tacrolimus on Cytokine-Challenged Human Islets
Authors: Balibrea Del Castillo Jose M. , García-Martín M. Cruz , Arias-Díaz Javier , Giné Elena , Vara Elena , Cantero Jose L. Balibrea
Published: January 2010

Our goal was to investigate whether previously related antiapoptotic and anti-inflammatory effects of tacrolimus could be useful in protecting human islets cultured in the presence of several proinflammatory mediators. Human islets obtained from cadaveric donors after intraductal infusion with collagenase, mechanical digestion, and continuous Ficoll gradient purification were cultured in RPMI-1640 medium for 24 h. Escherichia coli lipopolysaccharide (10 μg/ml) or interleukin-1 (50 UI/ml)+γ-IF (1000 UI/ml) and low-dose tacroliumus (5 ng/ml) were added. Homogenized samples (300 IE) from five different donors where assigned to four different experimental groups (control, treatment, cytokines, and cytokines + treatment). To evaluate islet damage and apoptotic response, nucleosome content, Bcl-2 protein levels, caspase-3, -8, and -9 levels, and insulin concentration were measured. Also, TNF-α and IL-6 levels where assessed as indicators of the inflammatory response. All proapoptotic markers, TNF-α, and IL-6 levels were augmented after both LPS and cytokine stimulation. Tacrolimus reduced significantly all of them and restored baseline values of nucleosome and caspase-9 in both experiments and Bcl-2 and caspase-3 when IL-1 + γ-IF was added. Twenty-four-hour insulin concentration diminished when LPS or IL-1 + γ-IF were present. Tacrolimus treatment restored insulin levels in both experiments. These results suggest that in vitro apoptotic events and media insulin concentration decrease after proinflammatory stimulation can be reverted using low-dose tacrolimus.
Protocols for Hematopoietic Stem Cell Expansion from Umbilical Cord Blood
Authors: Koestenbauer Sonja , Zisch Andreas , Dohr Gottfried , Zech Nicolas H.
Published: January 2010

The reconstitution of adult stem cells may be a promising source for the regeneration of damaged tissues and for the reconstitution of organ dysfunction. However, there are two major limitations to the use of such cells: they are rare, and only a few types exist that can easily be isolated without harming the patient. The best studied and most widely used stem cells are of the hematopoietic lineage. Pioneering work on hematopoietic stem cell (HSC) transplantation was done in the early 1970s by ED. Thomas and colleagues. Since then HSCs have been used in allogenic and autologous transplantation settings to reconstitute blood formation after high-dose chemotherapy for various blood disorders. The cells can be easily harvested from donors, but the cell number is limited, especially when the HSCs originate from umbilical cord blood (UCB). It would be desirable to set up an ex vivo strategy to expand HSCs in order to overcome the cell dose limit, whereby the expansion would favor cell proliferation over cell differentiation. This review provides an overview of the various existing HSC expansion strategies—focusing particularly on stem cells derived from UCB—of the parameters that might affect the outcome, and of the difficulties that may occur when trying to expand such cells.
Sex of Muscle Stem Cells Does Not Influence Potency for Cardiac Cell Therapy
Authors: Drowley Lauren , Okada Masaho , Payne Thomas R. , Botta Gregory P. , Oshima Hideki , Keller Bradley B. , Tobita Kimimasa , Huard Johnny
Published: January 2010

We have previously shown that populations of skeletal muscle-derived stem cells (MDSCs) exhibit sex-based differences for skeletal muscle and bone repair, with female cells demonstrating superior engrafting abilities to males in skeletal muscle while male cells differentiating more robustly toward the osteogenic and chondrogenic lineages. In this study, we tested the hypothesis that the therapeutic capacity of MDSCs transplanted into myocardium is influenced by sex of donor MDSCs or recipient. Male and female MDSCs isolated from the skeletal muscle of 3-week-old mice were transplanted into recipient male or female dystrophin-deficient ( mdx) hearts or into the hearts of male SCID mice following acute myocardial infarction. In the mdx model, no difference was seen in engraftment or blood vessel formation based on donor cell or recipient sex. In the infarction model, MDSC-transplanted hearts showed higher postinfarction angiogenesis, less myocardial scar formation, and improved cardiac function compared to vehicle controls. However, sex of donor MDSCs had no significant effects on engraftment, angiogenesis, and cardiac function. VEGF expression, a potent angiogenic factor, was similar between male and female MDSCs. Our results suggest that donor MDSC or recipient sex has no significant effect on the efficiency of MDSC-triggered myocardial engraftment or regeneration following cardiac injury. The ability of the MDSCs to improve cardiac regeneration and repair through promotion of angiogenesis without differentiation into the cardiac lineage may have contributed to the lack of sex difference observed in these models.
Long-Term Metabolic and Hormonal Effects of Exenatide on Islet Transplant Recipients with Allograft Dysfunction
Authors: Faradji Raquel N. , Froud Tatiana , Messinger Shari , Monroy Kathy , Pileggi Antonello , Mineo Davide , Tharavanij Thipaporn , Mendez Armando J. , Ricordi Camillo , Alejandro Rodolfo
Published: January 2010

The initial success of islet transplantation (ITx) is followed by graft dysfunction (GDF) and insulin reintroduction. Exenatide, a GLP-1 agonist, increases insulin and decreases glucagon secretion and has potential for β-cell regeneration. To improve functional islet mass, exenatide treatment was given to ITx recipients with GDF. The objective of this study was to assess metabolic and hormonal effects of exenatide in GDF. In this prospective, single-arm, nonrandomized study, 11 type 1 diabetes recipients of ITx with GDF had HbA1c, weight, insulin requirements, and 5-h mixed meal tolerance test (MMTT; with/without exenatide given before test) at baseline, 3, 6, and 12 months after initiating exenatide treatment. Baseline MMTT showed postprandial hyperglycemia and hyperglucagonemia. Daily exenatide treatment resulted in improved glucose, increased amylin/insulin ratio, and decreased proinsulin/insulin ratio as assessed by MMTT. Glucagon responses remained unchanged. Exenatide administration 1 h before MMTT showed decreased glucagon and glucose at 0 min and attenuation in their postprandial rise. Time-to-peak glucose was delayed, followed by insulin, proinsulin, amylin, and C-peptide, indicating glucose-driven insulin secretion. Five subjects completed 12-month follow-up. Glucose and glucagon suppression responses after MMTT with exenatide were no longer observed. Retrospective 3-month analysis of these subjects revealed higher and sustained glucagon levels that did not suppress as profoundly with exenatide administration, associated with higher glucose levels and increased C-peptide responses. In conclusion, Exenatide suppresses the abnormal postprandial hyperglucagonemia and hyperglycemia observed in GDF. Changes in amylin and proinsulin secretion may reflect more efficient insulin processing. Different degrees of responsiveness to exenatide were identified. These may help guide the clinical management of ITx recipients.
Quantitative Assessment of Islet Cell Products: Estimating the Accuracy of the Existing Protocol and Accounting for Islet Size Distribution
Authors: Buchwald Peter , Wang Xiaojing , Khan Aisha , Bernal Andres , Fraker Chris , Inverardi Luca , Ricordi Camillo
Published: January 2010

The ability to consistently and reliably assess the total number and the size distribution of isolated pancreatic islet cells from a small sample is of crucial relevance for the adequate characterization of islet cell preparations used for research or transplantation purposes. Here, data from a large number of isolations were used to establish a continuous probability density function describing the size distribution of human pancreatic islets. This function was then used to generate a polymeric microsphere mixture with a composition resembling those of isolated islets, which, in turn, was used to quantitatively assess the accuracy, reliability, and operator-dependent variability of the currently utilized manual standard procedure of quantification of islet cell preparation. Furthermore, on the basis of the best fit probability density function, which corresponds to a Weibull distribution, a slightly modified scale of islet equivalent number (IEQ) conversion factors is proposed that incorporates the size distribution of islets and accounts for the decreasing probability of finding larger islets within each size group. Compared to the current calculation method, these factors introduce a 4–8% downward correction of the total IEQ estimate, but they reflect a statistically more accurate contribution of differently sized islets.
Desert wildfire and severe drought diminish survivorship of the long‐lived Joshua tree (Yucca brevifolia; Agavaceae)
Authors: DeFalco Lesley A. , Esque Todd C. , Scoles‐Sciulla Sara J. , Rodgers Jane
Published: January 2010

Extreme climate events are transforming plant communities in the desert Southwest of the United States. Abundant precipitation in 1998 associated with El Niño Southern Oscillation (ENSO) stimulated exceptional alien annual plant production in the Mojave Desert that fueled wildfires in 1999. Exacerbated by protracted drought, 80% of the burned Yucca brevifolia, a long‐lived arborescent monocot, and 26% of unburned plants died at Joshua Tree National Park by 2004. Many burned plants <1 m tall died immediately, and survival of all but the tallest, oldest plants declined to the same low level by 2004. Postfire sprouting prolonged survival, but only at the wetter, high‐elevation sites. During succeeding dry years, herbaceous plants were scarce, and individuals of Thomomys bottae (pocket gopher) gnawed the periderm and hollowed stems of Y. brevifolia causing many of them to topple. Thomomys bottae damage reduced plant survivorship at low‐elevation, unburned sites and diminished survival of burned plants in all but the driest site, which already had low survival. Accentuated ENSO episodes and more frequent wildfires are expected for the desert Southwest and will likely shift Y. brevifolia population structure toward tall, old adults with fewer opportunities for plant recruitment, thus imperiling the persistence of this unique plant community.
Phylogenetics of Puya (Bromeliaceae): Placement, major lineages, and evolution of Chilean species
Authors: Jabaily Rachel Schmidt , Sytsma Kenneth J.
Published: January 2010

Puya (Bromeliaceae), a large genus of terrestrial bromeliads found throughout a range of elevations in the Andes and central Chile, is of great systematic, evolutionary, and biogeographical interest. This first molecular phylogenetic study of Puya and related bromeliads employs matK, trnS‐trnG, rps16, and PHYC sequences. Chloroplast DNA, nuclear DNA, and combined DNA data all place Puya closest to subfamily Bromelioideae. Nuclear and combined data support Puya as monophyletic, and the two subgenera are nonmonophyletic. All data indicate that the Chilean species of Puya are early diverging within the genus, consistent with Chilean genera as the first‐diverging members of subfamily Bromelioideae. Central Chile is identified as a key region for understanding the biogeographical history of Bromeliaceae, as is true with other South American plant groups. A complicated history involving early chloroplast capture and later secondary hybridization and/or introgression is seen in Chilean lineages. These events help explain the occurrence of sterile inflorescence tips, floral color and shape, and leaf indument. The ecological radiation of Puya appears coincident with the final, recent rise of the Andes and subsequent high‐elevation habitat diversification. Additionally, geographical distribution, rather than moisture or elevational adaptations, correlates to species relationships. Evolution of CAM photosynthesis has occurred multiple times.
Genetic effects of chronic habitat fragmentation revisited: Strong genetic structure in a temperate tree,Taxus baccata(Taxaceae), with great dispersal capability
Authors: Dubreuil Marta , Riba Miquel , González‐Martínez Santiago C. , Vendramin Giovanni G. , Sebastiani Federico , Mayol Maria
Published: January 2010

Tree species are thought to be relatively resistant to habitat fragmentation because of their longevity and their aptitude for extensive gene flow, although recent empirical studies have reported negative genetic consequences, in particular after long‐term habitat fragmentation in European temperate regions. Yet the response of each species to habitat loss may differ greatly depending on their biological attributes, in particular seed dispersal ability. In this study, we used demographic and molecular data to investigate the genetic consequences of chronic habitat fragmentation in remnant populations ofTaxus baccatain the Montseny Mountains, northeast Spain. The age structure of populations revealed demographic bottlenecks and recruitment events associated with exploitation and management practices. We found a strong genetic structure, both at the landscape and within‐population levels. We also detected high levels of inbreeding for a strictly outcrossing species. Chronic forest fragmentation resulting from long‐term exploitation in the Montseny Mountains seems the most plausible explanation for the strong genetic structure observed. Our results support the view that, contrary to some predictions, tree species are not buffered from the adverse effects of habitat fragmentation, even in the case of species with a high dispersal potential.
Evolution and polyploid origins in North American ArcticPuccinellia(Poaceae) based on nuclear ribosomal spacer and chloroplast DNA sequences
Authors: Consaul Laurie L. , Gillespie Lynn J. , Waterway Marcia J.
Published: January 2010

The proportion of polyploid plant species increases at higher latitudes, and it has been suggested that original postglacial Arctic immigrants of some large groups, including grasses, were polyploid. We analyzed noncoding nuclear and chloroplast DNA of all North American diploidPuccinellia(Poaceae) and a subset of arctic polyploids to hypothesize evolutionary relationships among diploids and to evaluate the parentage of polyploids. Diploids formed three lineages: one uniting arctic speciesP. arcticaandP. banksiensis; a second comprising arctic speciesP. tenella, P. alaskana, P. vahliana, andP. wrightii; and a third uniting the two temperate speciesP. lemmoniiandP. parishii. The arctic speciesP. angustata(hexaploid) andP. andersonii(primarily octoploid) apparently derive from theP. arctica‐P. banksiensislineage based on ITS and chloroplast sequences, and share an ancestor with arctic triploid/tetraploidP. phryganodesbased on nrDNA sequences. Sequence comparisons also suggest tetraploidP. bruggemanniievolved from two arctic lineages:P. vahliana‐P. wrightiiandP. arctica‐P. banksiensis. These patterns and the predominance of arctic rather than temperate diploid species support the idea that diploidPuccinelliarecolonized the Arctic from northern glacial refugia like Beringia, and also formed stabilized polyploid hybrids during these refugial events or subsequently during postglacial colonization.
Episodic migration of oaks to Iceland: Evidence for a North Atlantic “land bridge” in the latest Miocene
Authors: Denk Thomas , Grímsson Friðgeir , Zetter Reinhard
Published: January 2010

Dating the subsidence history of the North Atlantic Land Bridge (NALB) is crucial for understanding intercontinental disjunctions of northern temperate trees. Traditionally, the NALB has been assumed to have functioned as a corridor for plant migration only during the early Cenozoic, but recent findings of plant fossils and inferences from molecular studies are challenging this view. Here, we report dispersed pollen ofQuercusfrom Late Miocene sediments in Iceland that shows affinities with extant northern hemispheric white oaks and North American red oaks. Older (15 to 10 Ma) sediments do not contain pollen ofQuercussuggesting it arrived after that time. Pollen from the 9–8 Ma Hrútagil locality is indistinguishable from morphotypes common among white and red oaks. In contrast, pollen from the 5.5 Ma Selárgil locality has a tectum that is at present confined to North American white and red oaks, indicating a second episode of migration to Iceland. These findings suggest that transatlantic migration of temperate plant taxa may not have been limited by vast areas of sea or by cold climates during the Miocene. Furthermore, our results offer a plausible explanation for the remarkably low degree of genetic differentiation between modern disjunct European and North American oaks.
Genetic analyses of cell death in maize (Zea mays, Poaceae) leaves reveal a distinct pathway operating in the camouflage1 mutant
Authors: Huang Mingshu , Braun David M.
Published: January 2010

Controlled cell death is vital for many physiological processes in plants, such as xylem development, the hypersensitive response (HR), and senescence; however, the pathways governing cell death are incompletely understood. Studies of mutants that display a cell‐death phenotype have greatly contributed to our knowledge of how this process is regulated. The maize camouflage1 (cf1) mutant displays the novel phenotype of cell‐specific death of bundle sheath (BS) cells in discrete yellow leaf tissues. To investigate the BS cell death in cf1 mutants, we characterized potential underlying factors. Hydrogen peroxide (H2O2) is known to be involved in many cell‐death events in plants, including the HR. However, in vivo staining found no accumulation of H2O2 in cf1 mutant leaves. Additionally, genetic analyses determined that functional chloroplasts are required for cf1 BS cell death. These results demonstrate that cf1 BS cell death occurs via a distinct pathway from that seen in a functionally related maize mutant or in the HR, suggesting that cell death in maize leaves can be caused by multiple mechanisms.
Formation and function of a new pollen aperture pattern in angiosperms: The proximal sulcus of Tillandsia leiboldiana (Bromeliaceae)
Authors: Albert Béatrice , Matamoro‐Vidal Alexis , Raquin Christian , Nadot Sophie
Published: January 2010

Pollen grains are generally surrounded by an extremely resistant wall interrupted in places by apertures that play a key role in reproduction; pollen tube growth is initiated at these sites. The shift from a proximal to distal aperture location is a striking innovation in seed plant reproduction. Reversals to proximal aperture position have only very rarely been described in angiosperms. The genus Tillandsia belongs to the Bromeliaceae family, and its aperture pattern has been described as distal monosulcate, the most widespread aperture patterns recorded in monocots and basal angiosperms. Here we report developmental and functional elements to demonstrate that the sulcate aperture in Tillandsia leiboldiana is not distal as previously described but proximal. Postmeitotic tetrad observation indicates unambiguously the proximal position of the sulcus, and in vitro germination of pollen grains confirms that the aperture is functional. This is the first report of a sulcate proximal aperture with proximal germination. The observation of microsporogenesis reveals specific features in the patterns of callose thickenings in postmeiotic tetrads.
Pharmacokinetics of generic and trade formulations of lamivudine, stavudine and nevirapine in HIV-infected Malawian children
Authors: Corbett Amanda H , Hosseinipour Mina C , Nyirenda Jean , Kanyama Cecelia , Rezk Naser L , Mkupani Pax , Sichali Dorothy , Tien Hsiao , Kashuba Angela DM , Mwansambo Charles , Weigel Ralf , Kazembe Peter
Published: January 2010

Background

The aim of this study was to evaluate the pharmacokinetics of lamivudine (3TC), stavudine (d4T) and nevirapine (NVP) in HIV-infected Malawian children receiving quartered tablet multiples of Triomune 40™ (generic tablet [GT]) compared with individual generic liquid (GL) and trade liquid (TL).

Methods

This was a prospective randomized three-way crossover study. Patients (8–<12 kg, 18–<22 kg or 28–<32 kg body weight) taking Triomune 40™ were recruited and randomized to receive GT twice daily (one-quarter, one-half or three-quarter tablets using Malawi treatment guidelines), GL twice daily (in the equivalent dose of GT) or TL twice daily (dosed using weight and age from US Department of Health and Human Services paediatric treatment guidelines). After 10 days of one formulation, 6-h pharmacokinetic sampling was performed, and patients were crossed over to subsequent formulations. Baseline concentration (C0 h), area under the curve (AUC)0-6 h, maximum plasma concentration (Cmax) and time to Cmax were generated for each antiretroviral treatment.

Results

A total of 7 males and 11 females (6 in each GT dosing group) with a median (range) age of 7.2 years (1.3– 13.6), weight of 19 kg (9.0–30.5) and height of 109 cm (75–132) were recruited. Combining all patients, no difference in pharmacokinetics was noted among the formulations for all drugs. However, patients in the one-quarter GT dosing group (8–<12 kg) had lower 3TC exposures than with the GL or TL (3TC AUC0-6 h 1,102, 1,720 and 2,060 h•ng/ml, respectively; P<0.005) and had more subtherapeutic NVP C0 h (10 of 13 occasions versus the one-half and three-quarter tablet groups). Compared with Western paediatric cohorts, Malawians had concentrations 30–40% lower for 3TC and d4T and 50% higher for NVP.

Conclusions

Quartered multiples of Triomune 40™ are appropriate for children 18–<22 kg and 28–<32 kg in weight; however, alternative formulations are suggested in children weighing 8–<12 kg.
Disease Severity in Ankylosing Spondylitis: Variation by Region and Local Area Deprivation
Authors: HEALEY EMMA L. , HAYWOOD KIRSTIE L. , JORDAN KELVIN P. , GARRATT ANDREW M. , PACKHAM JONATHAN C.
Published: January 2010

Objective.

To investigate whether patient disease severity in ankylosing spondylitis (AS) varies among regions or by local area social deprivation.

Methods.

Eight hundred patients with AS from 8 specialist rheumatology centers across England were invited to participate in a cross-sectional survey. Sociodemographic and disease-related variables were collected [pain (numerical rating scale), disease activity (Bath AS Disease Activity Index), and physical function (Bath AS Functional Index)]. Deprivation was measured using the Index of Multiple Deprivation 2004.

Results.

Of the 800 patients invited, 468 responded (adjusted response rate 62.8%). Most were male (72.9%), with a mean age of 50.2 years (SD 12.1), and a mean diagnosed disease duration of 17 years (SD 11.4). Across all centers, those living in more deprived areas demonstrated significantly greater disease severity and poorer psychological health. After controlling for age, gender, disease duration, and region, greater deprivation was significantly associated with greater disease activity (OR 3.39; 95% CI 1.65, 6.98) and poorer function (OR 4.46; 95% CI 2.11, 9.44). There was a nonsignificant trend toward more pain (OR 1.98; 95% CI 0.97, 4.07). There was also a significant independent association between region and disease severity.

Conclusion.

The need for healthcare is greatest for patients with AS who are living in more socially deprived areas. With the growing use of interventional therapies, these findings have important implications if health service resources are to be allocated equitably; particularly as deprived patients are known to access healthcare less frequently.
A Common European Song Heritage in the Nineteenth Century Songs of Ireland and Germany
Authors: Robb David
Published: January 2010

This paper deals with thematic similarities between German and Irish folk songs of the nineteenth century, particularly the period surrounding the 1848 Revolution. While clear commonalities can be seen to exist in songs about exploitative masters, hunger, emigration and army recruitment, there are differences in terms of the situation of Germany as a rapid industrialising nation while Ireland was still rural. At the same time the plight of the displaced German craftsmen due to industrialisation does have echoes in the struggles of the craft trade expressed in the Irish songs. Another difference lies in the dimension of religion and national liberation in the Irish ballads, whereas the German counterparts display more of a developing class consciousness. While the German and Irish narrative styles and approaches also differ from one another, there is nonetheless evidence of a common folk language and musical heritage between the two countries, which has been affirmed by the cultural exchange between their respective folk movements since the 1970s.
***
Članek obravnava vsebinske podobnosti med nemškimi in irskimi ljudskimi pesmimi iz 19. stoletja, posebej še iz časa okrog revolucionarnih sprememb leta 1848. Medtem ko lahko opazimo izrazite podobnosti v pesmih, ki pojejo o izkoriščevalskih gospodarjih, emigraciji in vojaških vpoklicih, pa so opazne razlike med Nemčijo kot deželo izrazite indistrializacije in Irsko kot še vedno zelo ruralno deželo. Istočasno pa težak položaj zaradi industrializacije razseljenih nemških rokodelcev odmeva v tistih irskih pesmih o rokodelstvu. Druga je razlika v religiji in nacionalni osvoboditvi, kakor odsevata v irskih baladah, medtem ko nemške balade bolj izražajo razvijajočo se razredno zavest. Tudi pripovedna struktura in slog obeh nacionalnih tradicij se razlikujeta, sta pa kljub temu opazna podoben jezik in glasbeno izročilo, kar je potrdila kulturna izmenjava med irskim in nemškim preporodom ljudskega od leta 1970 naprej.
Christmas Songs and Constructing Identities
Authors: Klobčar Marija
Published: January 2010

The basic question addressed in this paper – “Is there a European song heritage or a European heritage in songs?” – is not just a question of Europe, heritage and songs: it leads to the deeper issue of identity that extends beyond national frameworks. The study of these issues cannot ignore the struggle for national identity, ideological differences, contemporary political tensions, and globalization. Taking all of these into consideration, can Europe be understood as a special cultural space with its expression in or using songs, or is it just a new imagined community? – For this kind of study, Slovenian ethnic territory offers remarkable opportunities due to its exceptional historical and spatial meeting points. By concentrating on Christmas songs this paper seeks to determine what the past influences were upon the image of the Slovenian Christmas experience. This study also examines how communism, which relegated the celebration of Christmas to the private sphere, influenced these songs and the Christmas experience, as well as the kinds of changes engendered by Slovenian independence and transition, when the market and the media entered Slovenians’ home lives and Christmas became part of the public sphere. This paper considers these processes in order to address the question of the relationship between song heritage and concepts of identification.
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Izhodiščno vprašanje – »Ali obstaja evropska dediščina pesmi ali evropska dediščina v pesmih« – ni le vprašanje Evrope, dediščine in pesmi: vodi k globljemu razmisleku o identiteti, ki presega nacionalne okvire. Ob opazovanju tega problema ne moremo mimo iskanja nacionalne identitete, ideoloških razločkov, sočasnih političnih pritiskov in globalizacije. Ali lahko Evropo – upoštevajoč vse te značilnosti – razumemo kot posebni kulturni prostor, ki se izraža tudi v pesmih ali z njimi, ali je to le nova umišljena skupnost? – Slovenski etnični prostor zaradi posebnih zgodovinskih in prostorskih stičišč za tak premislek ponuja izredne možnosti. S pozornostjo do božičnih pesmi tako skuša prispevek ugotoviti, kaj vse je vplivalo na podobo slovenskega doživljanja božiča v preteklosti, kako je na pesmi in na doživljanje božiča vplival socializem, ki je praznovanje božiča potisnil v zasebnost, in kakšne spremembe sta prinesli slovenska osamosvojitev in tranzicija, ko sta tržišče in medijski prostor vstopila v zasebni svet Slovencev, božič pa je postal del javnega življenja. Z opazovanjem teh procesov prispevek odpira tudi vprašanja o razmerju med pesemsko dediščino in koncepti identifikacije.
A NEW SPECIES OF BEAN LEAFHOPPER FROM HAITI
Authors: Delong Dwight M.
Published: January 2010

Resembling fabae in size, form and appearance, but with distinct genital characters. Size 3 mm.

Vertex strongly produced about one third its length before anterior margins of eyes. One third wider between eyes than length at middle. Pronotum one-third longer than vertex.
Intracellular MHC Class II Controls Regulatory Tolerance to Allogeneic Transplants
Authors: LeGuern Christian , Akiyama Yoshinobu , Germana Sharon , Tanaka Katsunori , Fernandez Luis , Iwamoto Yoshiko , Houser Stuart , Benichou Gilles
Published: January 2010

MHC class II (MHCII) genes have been implicated in the regulation of T lymphocyte responses. However, the mechanism of MHCII-driven regulation remains unknown. Matching for MHCII between donors and recipients of allografts favors regulatory T cell tolerance to transplants and provides a unique opportunity to study this regulation. In this study, we investigated MHCII regulation using transfer of donor MHCII genes in recipients of cardiac allografts. Transfer of MHCII IAb genes in the bone marrow of CBA mice (H-2k) prior to the grafting of IAb+ fully allogeneic C57BL/6 (B6, H-2b) heart transplants resulted in donor-specific tolerance associated with long-term survival of B6, but not third-party, allografts without sustained immunosuppression. Strikingly, the majority of accepted heart transplants (>170 d) were devoid of allograft vasculopathy. Further studies indicated that intracellular IAb initiated the tolerogenic process, which was mediated by regulatory T cells (Tregs) that polarized antigraft responses to Th2 cytokine producers. This mechanism seems to be unique to MHCII genes, because previous MHC class I gene-based therapies failed to produce Tregs. These results demonstrate the key role of MHCII in the induction of Tregs. They also underscore a potential mechanism of specific inactivation of T cells in this model; when activated by IAb+ grafts, IAb-specific Tregs repress the entire alloresponse to C57BL/6 transplants (including MHC I and minor Ags), thus mediating T cell tolerance.
NFAT1 Mediates Placental Growth Factor-Induced Myelomonocytic Cell Recruitment via the Induction of TNF-α
Authors: Ding Yanping , Huang Yujie , Song Nan , Gao Xiaobin , Yuan Shaopeng , Wang Xiaofeng , Cai Hongchen , Fu Yan , Luo Yongzhang
Published: January 2010

Recruitment of bone marrow-derived myelomonocytic cells plays a fundamental role in tumor angiogenesis and metastasis. Placental growth factor (PlGF) is a potent cytokine that can attract myelomonocytic cells to the tumor. However, the underlying mechanism remains obscure. In this study, we demonstrate that tumor-derived PlGF activates NFAT1 via vascular endothelial growth factor receptor 1 in both murine and human myelomonocytic cells. Activation of NFAT1 is crucial for PlGF-induced myelomonocytic cell recruitment as shown by the in vitro transwell migration assay, transendothelial migration assay, and PlGF-overexpressing tumor models in mice, respectively. TNF-α is upregulated by PlGF in myelomonocytic cells in an NFAT1-dependent manner, which in turn contributes to PlGF-induced myelomonocytic cell recruitment. Blockade of TNF-α expression by RNA interference or neutralization of secreted TNF-α with its Ab attenuates PlGF-induced myelomonocytic cell migration and transendothelial migration. Furthermore, the inhibitory effect of NFAT1 RNA interference on PlGF function is rescued by exogenously added TNF-α. Taken together, we demonstrate that NFAT1 mediates PlGF-induced myelomonocytic cell recruitment via the induction of TNF-α. Our present studies discover a novel role of the NFAT1–TNF-α pathway in tumor inflammation, which may provide potential targets to diversify current cancer therapy.
Arginase II Restricts Host Defense toHelicobacter pyloriby Attenuating Inducible Nitric Oxide Synthase Translation in Macrophages
Authors: Lewis Nuruddeen D. , Asim Mohammad , Barry Daniel P. , Singh Kshipra , de Sablet Thibaut , Boucher Jean-Luc , Gobert Alain P. , Chaturvedi Rupesh , Wilson Keith T.
Published: January 2010

Helicobacter pylori infection of the stomach causes peptic ulcer disease and gastric cancer. Despite eliciting a vigorous immune response, the bacterium persists for the life of the host. An important antimicrobial mechanism is the production of NO derived from inducible NO synthase (iNOS). We have reported that macrophages can kill H. pylori in vitro by an NO-dependent mechanism, but supraphysiologic levels of the iNOS substrate l-arginine are required. Because H. pylori induces arginase activity in macrophages, we determined if this restricts NO generation by reducing l-arginine availability. Inhibition of arginase with S-(2-boronoethyl)-l-cysteine (BEC) significantly enhanced NO generation in H. pylori-stimulated RAW 264.7 macrophages by enhancing iNOS protein translation but not iNOS mRNA levels. This effect resulted in increased killing of H. pylori that was attenuated with an NO scavenger. In contrast, inhibition of arginase in macrophages activated by the colitis-inducing bacterium Citrobacter rodentium increased NO without affecting iNOS levels. H. pylori upregulated levels of arginase II (Arg2) mRNA and protein, which localized to mitochondria, whereas arginase I was not induced. Increased iNOS protein and NO levels were also demonstrated by small interfering RNA knockdown of Arg2 and in peritoneal macrophages from C57BL/6 Arg2−/− mice. In H. pylori-infected mice, treatment with BEC or deletion of Arg2 increased iNOS protein levels and NO generation in gastric macrophages, but treatment of Arg2−/− mice with BEC had no additional effect. These studies implicate Arg2 in the immune evasion of H. pylori by causing intracellular depletion of l-arginine and thus reduction of NO-dependent bactericidal activity.
FcγRIIB Inhibits the Development of Atherosclerosis in Low-Density Lipoprotein Receptor-Deficient Mice
Authors: Zhao Ming , Wigren Maria , Dunér Pontus , Kolbus Daniel , Olofsson Katarina E. , Björkbacka Harry , Nilsson Jan , Fredrikson Gunilla Nordin
Published: January 2010

The immune processes associated with atherogenesis have received considerable attention during recent years. IgG FcRs (FcγR) are involved in activating the immune system and in maintaining peripheral tolerance. However, the role of the inhibitory IgG receptor FcγRIIB in atherosclerosis has not been defined. Bone marrow cells from FcγRIIB-deficient mice and C57BL/6 control mice were transplanted to low-density lipoprotein receptor-deficient mice. Atherosclerosis was induced by feeding the recipient mice a high-fat diet for 8 wk and evaluated using Oil Red O staining of the descending aorta at sacrifice. The molecular mechanisms triggering atherosclerosis was studied by examining splenic B and T cells, as well as Th1 and Th2 immune responses using flow cytometry and ELISA. The atherosclerotic lesion area in the descending aorta was ~5-fold larger in mice lacking FcγRIIB than in control mice (2.75 ± 2.57 versus 0.44 ± 0.42%; p < 0.01). Moreover, the FcγRIIB deficiency resulted in an amplified splenocyte proliferative response to Con A stimulation (proliferation index 30.26 ± 8.81 versus 2.96 ± 0.81%, p < 0.0001) and an enhanced expression of MHC class II on the B cells (6.65 ± 0.64 versus 2.33 ± 0.25%; p < 0.001). In accordance, an enlarged amount of CD25-positive CD4 T cells was found in the spleen (42.74 ± 4.05 versus 2.45 ± 0.31%; p < 0.0001). The plasma Ab and cytokine pattern suggested increased Th1 and Th2 immune responses, respectively. These results show that FcγRIIB inhibits the development of atherosclerosis in mice. In addition, they indicate that absence of the inhibiting IgG receptor cause disease, depending on an imbalance of activating and inhibiting immune cells.
Functionally Significant Differences in Expression of Disease-Associated IL-7 Receptor α Haplotypes in CD4 T Cells and Dendritic Cells
Authors: Hoe Edwin , McKay Fiona C. , Schibeci Stephen D. , Gandhi Kaushal , Heard Rob N. , Stewart Graeme J. , Booth David R.
Published: January 2010

Common genetic variants of IL-7 receptor α (IL-7Rα) have recently been shown to affect susceptibility to multiple sclerosis (MS) and type 1 diabetes, and survival following bone marrow transplantation. Transcription of the gene produces two dominant isoforms, with or without exon 6, which code for membrane-bound or soluble IL-7Rα, respectively. The haplotypes produce different isoform ratios. We have tested IL-7Rα mRNA expression in cell subsets and in models of T cell homeostasis, activation, tolerance, and differentiation into regulatory T cell/Th1/Th2/Th17, memory, and dendritic cells (DCs) under the hypothesis that the conditions in which haplotype differences are maximal are those likely to be the basis for their association with disease pathogenesis. Maximal differences between haplotypes were found in DCs, where the ligand is mainly thymic stromal lymphopoietin (TSLP). The MS-protective haplotype produces a much lower ratio of soluble to membrane-bound receptor, and so potentially, DCs of this haplotype are more responsive to TSLP. The TSLP/IL-7Rα interaction on DCs is known to be critical for production of thymic regulatory T cells, and reduced production of these cells in MS susceptibility haplotypes may be a basis for its association with this disease. IL-7Rα mRNA expression varies greatly through cell differentiation so that it may be a useful marker for cell states. We also show that serum levels of soluble receptor are much higher for the MS susceptibility haplotype (p = 4 × 10−13). Because signaling through IL-7Rα controls T cell regulation, this haplotype difference is likely to affect the immunophenotype and disease pathogenesis.