bluuebunny/crossref_metadata_2025_split huggingface dataset:
Comparative analysis of mononuclear cells isolated from mucosal lymphoid follicles of the human ileum and colon
Authors: Junker Y , Bode H , Wahnschaffe U , Kroesen A , Loddenkemper C , Duchmann R , Zeitz M , Ullrich R 
Published: January 2009

SummaryStudies of human mucosal lymphoid follicles are rare and have been limited to children's Peyer's patches, which are visible at endoscopy. We investigated lymphoid follicles in ileum biopsies of 87 patients and surgical colon specimens from 66 cancer patients, and examined phenotype and function of isolated follicular immune cells. Two (0–10) and 12 (0–117) follicles per patient were found in ileum and colon samples respectively (P &lt; 0·001). The number of lymphoid follicles mononuclear cells (LFMC) that could be isolated per patient was higher from colon compared with ileum specimens [725 000 (0–23 Mio) versus 100 000 (0–1·3 Mio), P &lt; 0·001]. T cells were predominant in both LFMC and lamina propria mononuclear cells (LPMC), but B cells were more and plasma cells less frequent in LFMC. T cells from mucosal follicles were more frequently CD4-positive and CD62L-positive, but less frequently CD8-positive, CD103-positive and CD69-positive than lamina propria T cells. LFMC from ileum compared with colon showed no differences in mononuclear cell composition. Anti-CD3/CD28 stimulation induced similar proliferation of LFMC and LPMC from ileum and colon, as well as secretion of high levels of interferon-γ, tumour necrosis factor-α and interleukin (IL)-2, but lower levels of IL-4, IL-6 and IL-10. LFMC from colon secreted more IL-2 than those from ileum. Our study shows that mucosal lymphoid follicles can be identified clearly in adult human colon and yield viable immune cells sufficient for phenotypical and functional analysis. The cellular composition of LFMC from ileum and colon is similar, and both secrete predominantly T helper type 1 cytokines.
Depth and shape estimates from simultaneous inversion of magnetic fields and their gradient components using differential similarity transforms
Authors: Stavrev Petar , Gerovska Daniela , Araúzo‐Bravo Marcos J. 
Published: January 2009

ABSTRACTThe differential similarity transform of a magnetic anomaly is a linear combination of its intensity and gradient components. This transform is sensitive to the distance between a chosen central point of similarity and the source and depends on the degree of homogeneity of the field. Taking advantage of this property, a new field inversion method resulting in the evaluation of source position and shape type is proposed and implemented. The field gradient components are measured directly in magnetic gradiometry, or they can be calculated from the measured field data. Regional and local linear backgrounds are accounted for by the method. The method can be applied on either regularly or irregularly‐spaced data sets, on even or uneven surfaces of observation. The solving of the systems of equations is not necessary. A semi‐automated inversion for both location and shape of the sources is implemented. Model and field tests illustrate the effectiveness of the proposed inversion technique for depth and shape estimates.
Use of stored carbon reserves in growth of temperate tree roots and leaf buds: analyses using radiocarbon measurements and modeling
Authors: GAUDINSKI J. B. , TORN M. S. , RILEY W. J. , SWANSTON C. , TRUMBORE S. E. , JOSLIN J. D. , MAJDI H. , DAWSON T. E. , HANSON P. J. 
Published: January 2009

AbstractCharacterizing the use of carbon (C) reserves in trees is important for understanding regional and global C cycles, stress responses, asynchrony between photosynthetic activity and growth demand, and isotopic exchanges in studies of tree physiology and ecosystem C cycling. Using an inadvertent, whole‐ecosystem radiocarbon (14C) release in a temperate deciduous oak forest and numerical modeling, we estimated that the mean age of stored C used to grow both leaf buds and new roots is 0.7 years and about 55% of new‐root growth annually comes from stored C. Therefore, the calculated mean age of C used to grow new‐root tissue is ∼0.4 years. In short, new roots contain a lot of stored C but it is young in age. Additionally, the type of structure used to model stored C input is important. Model structures that did not include storage, or that assumed stored and new C mixed well (within root or shoot tissues) before being used for root growth, did not fit the data nearly as well as when a distinct storage pool was used. Consistent with these whole‐ecosystem labeling results, the mean age of C in new‐root tissues determined using ‘bomb‐14C’ in three additional forest sites in North America and Europe (one deciduous, two coniferous) was less than 1–2 years. The effect of stored reserves on estimated ages of fine roots is unlikely to be large in most natural abundance isotope studies. However, models of root C dynamics should take stored reserves into account, particularly for pulse‐labeling studies and fast‐cycling roots (<1 years).
Physiological responses of two contrasting desert plant species to precipitation variability are differentially regulated by soil moisture and nitrogen dynamics
Authors: PATRICK LISA D. , OGLE KIONA , BELL COLIN W. , ZAK JOHN , TISSUE DAVID 
Published: January 2009

AbstractAlterations in global and regional precipitation patterns are expected to affect plant and ecosystem productivity, especially in water‐limited ecosystems. This study examined the effects of natural and supplemental (25% increase) seasonal precipitation on a sotol grassland ecosystem in Big Bend National Park in the Chihuahuan Desert. Physiological responses – leaf photosynthesis at saturating light (Asat), stomatal conductance (gs), and leaf nitrogen [N] – of two species differing in their life form and physiological strategies (Dasylirion leiophyllum, a C3shrub;Bouteloua curtipendula, a C4grass) were measured over 3 years (2004–2006) that differed greatly in their annual and seasonal precipitation patterns (2004: wet, 2005: average, 2006: dry). Precipitation inputs are likely to affect leaf‐level physiology through the direct effects of altered soil water and soil nitrogen. Thus, the effects of precipitation, watering treatment, soil moisture, and nitrogen were quantified via multivariate hierarchical Bayesian models that explicitly linked the leaf and soil responses. The two species differed in their physiological responses to precipitation and were differentially controlled by soil water vs. soil nitrogen. In the relatively deeply rooted C3shrub,D. leiophyllum, Asatwas highest in moist periods and was primarily regulated by deep (16–30 cm) soil water. In the shallow‐rooted C4grass,B. curtipendula, Asatwas only coupled to leaf [N], both of which increased in dry periods when soil [N] was highest. Supplemental watering during the wet year generally decreasedAsatand leaf [N] inD. leiophyllum, perhaps due to nutrient limitation, and physiological responses in this species were influenced by the cumulative effects of 5 years of supplemental watering. Both species are common in this ecosystem and responded strongly, yet differently, to soil moisture and nitrogen, suggesting that changes in the timing and magnitude of precipitation may have consequences for plant carbon gain, with the potential to alter community composition.
Estimating colonization potential of migrant tree species
Authors: IBÁÑEZ INÉS , CLARK JAMES S. , DIETZE MICHAEL C. 
Published: January 2009

AbstractPlant populations migrating in response to climate change will have to colonize established communities. Even if a population disperses to a new region with a favorable climate, interactions with other species may prevent its establishment and further spread. The potential of these species to grow along with residents will be a critical factor controlling their response to climate change. To determine the capacity of migrating species to colonize established communities we conducted extensive long‐term transplant experiments where potential tree migrant species, i.e. species within ‘migration range,’ were planted side by side with resident ones. Potential immigrants were selected to be representative species of their native communities. For both groups, residents and potential migrants (17 species), we compared their growth response along gradients in soil moisture and light availability. Rather than manipulate climate directly, we exploited natural microclimatic gradients and the fluctuations in climate that occurred during the 5‐year experiment. Experimental results were used to estimate growth in the context of novel climate and relevant establishment factors. Results suggest that potential immigrant species had similar growth rates in the new environment than those from resident species ensuring their ability to establish in the area. However, contrary to our expectations, the soil moisture requirements for the immigrant group were similar to those of the resident species. These results could have major implications for vegetation changes under the predicted drier climate for the region. If it is the case that neither resident species nor potential migrants are able to maintain stable populations, the region may experience a decline in local biodiversity.
Spontaneous complement activation on human B cells results in localized membrane depolarization and the clustering of complement receptor type 2 and C3 fragments
Authors: Løbner Morten , Leslie Robert G. Q. , Prodinger Wolfgang M. , Nielsen Claus H. 
Published: January 2009

SummaryWhile our previous studies have demonstrated that complement activation induced by complement receptors type 2 (CR2/CD21) and 1 (CR1/CD35) results in C3‐fragment deposition and membrane attack complex (MAC) formation in human B cells, the consequences of these events for B‐cell functions remain unknown. In the present study, we show that CR2‐induced complement activation results in membrane depolarization, as indicated by annexin V binding, with kinetics similar to those of C3‐fragment deposition and different from those of MAC formation. On the other hand, like MAC formation, depolarization requires activation of complement via the alternative pathway, as indicated by total inhibition upon neutralization of factor D, and is abrogated by combined blockade of CR1 and CR2, but not of either receptor alone. The membrane depolarization is not associated with the apoptosis of B cells, as examined by co‐staining with APO‐2.7 or by the TdT‐mediated biotin–dUTP nick‐end labelling (TUNEL) assay. Confocal microscopy revealed that depolarization and C3 deposition, unlike MAC deposition, are limited to restricted areas on the B‐cell surface. Double staining revealed a close association between the C3‐fragment patches and membrane depolarization, as well as redistribution of lipid rafts to these areas. We propose that these events may play a role in the regulation of B‐cell signalling and cross‐talk with T cells.
Genetic and epigenetic networks controlling T helper 1 cell differentiation
Authors: Placek Katarzyna , Coffre Maryaline , Maiella Sylvie , Bianchi Elisabetta , Rogge Lars 
Published: January 2009

SummarySignificant progress has been made during the past years in our understanding of the mechanisms that control the differentiation of naïve CD4+ T cells into effector T‐cell subsets with distinct functional properties. Previous work allowed the identification of key molecules involved in regulating this highly complex process, such as cytokines and their receptors, signal transducers and transcription factors. More recently, the emphasis of research in this field has been to elucidate how the multiplicity of signals is integrated to shape a T helper subset‐specific gene‐expression program controlling differentiation and effector functions. In this review we will highlight advances that have been made in unravelling the genetic and epigenetic networks controlling differentiation of naïve CD4+ T cells into interferon‐γ(IFN‐γ)‐secreting T helper type 1 (Th1) cells.
Acid stress activation of the σE stress response in Salmonella enterica serovar Typhimurium
Authors: Muller Cécile , Bang Iel‐Soo , Velayudhan Jyoti , Karlinsey Joyce , Papenfort Kai , Vogel Jörg , Fang Ferric C. 
Published: January 2009

SummaryThe alternative sigma factor σE is activated by unfolded outer membrane proteins (OMPs) and plays an essential role in Salmonella pathogenesis. The canonical pathway of σE activation in response to envelope stress involves sequential proteolysis of the anti‐sigma factor RseA by the PDZ proteases DegS and RseP. Here we show that σE in Salmonella enterica sv. Typhimurium can also be activated by acid stress. A σE‐deficient mutant exhibits increased susceptibility to acid pH and reduced survival in an acidified phagosomal vacuole. Acid activation of σE‐dependent gene expression is independent of the unfolded OMP signal or the DegS protease but requires processing of RseA by RseP. The RseP PDZ domain is indispensable for acid induction, suggesting that acid stress may disrupt an inhibitory interaction between RseA and the RseP PDZ domain to allow RseA proteolysis in the absence of antecedent action of DegS. These observations demonstrate a novel environmental stimulus and activation pathway for the σE regulon that appear to be critically important during Salmonella–host cell interactions.
Cultural enhancement of a clinical service to meet the needs of indigenous people; genetic service development in response to issues for New Zealand Maori
Authors: Port RV , Arnold J , Kerr D , Gravish N , Winship I 
Published: January 2009

The delivery of good health care services within clinical settings is predicated by an understanding of the needs of the stakeholders*. Most of the information generated to date on the transfer of mutational analysis to clinical service has been within a Eurocentric model favouring individual autonomy. It is predictable that this model does not easily translate for other cultures.Current genetic technology has elucidated the molecular basis of many diseases. In familial cancer and other late‐onset disorders, there is now the possibility of ‘prediction’ where a high risk conferred by family history can be confirmed or negated by genetic testing. In paediatric disorders, prediction is offered in the form of prenatal or pre‐implantation genetic diagnosis. We report on the processes undertaken in an attempt to provide a culturally sensitive service for the Maori people of Aotearoa, New Zealand.
Mutations in sarcomeric protein genes not only lead to cardiomyopathy but also to congenital cardiovascular malformations
Authors: Wessels Marja W. , Willems Patrick J. 
Published: January 2009

Noncompaction of the ventricular myocardium is associated with de novo mutation in the beta‐myosin heavy chain gene Budde et al. (2007) PLoS ONE 2: e1362Homozygosity for a novel splice site mutation in the cardiac myosin‐binding protein C gene causes severe neonatal hypertrophic cardiomyopathy Xin et al. (2007) Am J Med Genet 143: 2662–2667Alpha‐cardiac actin mutations produce atrial septal defects Matsson et al. (2008) Hum Mol Genet 17: 256–265
Comparison of intrathecal magnesium, fentanyl, or placebo combined with bupivacaine 0.5% for parturients undergoing elective cesarean delivery
Authors: UNLUGENC H. , OZALEVLI M. , GUNDUZ M. , GUNASTI S. , URUNSAK I. F. , GULER T. , ISIK G. 
Published: January 2009

Background: Intrathecal (i.t.) administration of magnesium has been reported to potentiate opioid antinociception in rats and humans. In this prospective, randomized, double‐blind, study, we investigated the sensory, motor, and analgesic block characteristics of i.t. magnesium 50 mg compared with fentanyl 25 μg and saline when added to 0.5% bupivacaine (10 mg).Methods: Ninety ASA I or II adult patients undergoing cesarean section were randomly allocated to receive 1.0 ml of 0.9% sodium chloride in group S, 50 mg of magnesium sulfate (1.0 ml) 5% in group M, or 25 μg of fentanyl (1.0 ml) in group F following 10 mg of bupivacaine 0.5% i.t. We recorded the following: onset and duration of sensory and motor block, maximal sensory block height, the time to reach the maximal dermatomal level of sensory block, and the duration of spinal anesthesia.Results: Magnesium did not shorten the onset time of sensory and motor blockade or prolong the duration of spinal anesthesia. The duration of sensory (P<0.032) and motor (P<0.002) blockade was significantly shorter in M and S groups than in the F group. The time to reach the maximal dermatomal level of sensory block was significantly shorter in the F group than in the S and M groups (P<0.002).Conclusion: In patients undergoing cesarean section with spinal anesthesia, the addition of magnesium sulfate (50 mg) i.t. to 10 mg of spinal bupivacaine (0.5%) did not shorten the onset time of sensory and motor blockade or prolong the duration of spinal anesthesia, as seen with fentanyl.
Depth of anaesthesia monitoring in obese patients: a randomized study of propofol–remifentanil
Authors: MEYHOFF C. S. , HENNEBERG S. W. , JØRGENSEN B. G. , GÄTKE M. R. , RASMUSSEN L. S. 
Published: January 2009

Background: In obese patients, depth of anaesthesia monitoring could be useful in titrating intravenous anaesthetics. We hypothesized that depth of anaesthesia monitoring would reduce recovery time and use of anaesthetics in obese patients receiving propofol and remifentanil.Methods: We investigated 38 patients with a body mass index ≥30 kg/m2 scheduled for an abdominal hysterectomy. Patients were randomized to either titration of propofol and remifentanil according to a cerebral state monitor (CSM group) or according to usual clinical criteria (control group). The primary end point was time to eye opening and this was assessed by a blinded observer.Results: Time to eye opening was 11.8 min in the CSM group vs. 13.4 min in the control group (P=0.58). The average infusion rate for propofol was a median of 516 vs. 617 mg/h (P=0.24) and for remifentanil 2393 vs. 2708 μg/h (P=0.04). During surgery, when the cerebral state index was continuously between 40 and 60, the corresponding optimal propofol infusion rate was 10 mg/kg/h based on ideal body weight.Conclusion: No significant reduction in time to eye opening could be demonstrated when a CSM was used to titrate propofol and remifentanil in obese patients undergoing a hysterectomy. A significant reduction in remifentanil consumption was found.
Preliminary Studies on Cryopreservation of Common Tench (Tinca tinca) Embryos (Work in Progress)
Authors: El‐Battawy KA , Linhart O 
Published: January 2009

ContentsVitrification could provide a promising tool for the cryopreservation of fish embryos. However, to achieve cryopreservation using vitrification, chilling sensitivity and cryoprotectants toxicity were determined using tench embryos at four developmental stages (11, 17, 23 and 29 h). Embryos treated with alcalase (2 ml/998 ml, 2 min at 22°C) were exposed to chilling with/without warming. Other embryos were exposed to methanol and glycerol at the concentration of 10% and 20% for periods of 20 min. At last, embryos were incubated at special incubator cages where hatching rates were counted. Regarding chilling sensitivity and exposure to chilling followed by warming, the hatching rates of embryos decreased significantly (p < 0.001) after exposure to 0°C at all developmental stages except the 29‐h stage compared with the controls. The embryo stage most sensitive to chilling was 11‐h stage. The 29‐h stage exhibited the least sensitivity to low temperature while 17‐h and 23‐h stages were intermediate in their sensitivity to chilling. The toxicity of methanol increased significantly (p < 0.001) with developmental stage for 11, 17 and 23‐h stages. The highest hatching rates of tench embryos were obtained with 29‐h embryos using various concentrations of methanol. The hatching rates of tench embryos exposed to glycerol concentrations were approximately similar to those embryos exposed to methanol concentrations except for 11‐h embryos that showed no hatching. Unfortunately, we could not obtain living embryos in any of the conditions examined after vitrification. In conclusion, it was quite difficult to vitrify the tench embryos during this study using various vitrifying solutions and the method reported by Chen & Tian (2005) and further studies are needed to achieve successful cryopreservation.
Cortisol Profiles in Sows Submitted to an Intermittent Suckling Regime Compared with that of Abruptly Weaned Sows
Authors: Kluivers‐Poodt M , Gerritsen R , Van Nes A , Langendijk P 
Published: January 2009

ContentsThe aim of this study was to monitor changes in cortisol levels in sows around the time of separation from their piglets, in two different intermittent suckling regimes, compared with that in conventionally weaned sows. Sows were either weaned at 21 days of lactation (CONT) or subjected to an intermittent suckling regime (IS) from 14 days of lactation onwards. Sows in the IS regimes were separated from their piglets for 12 h every day, either from 08:00 to 20:00 hours (IS12) or from 08:00 to 14:00 hours and 20:00 to 02:00 hours (IS6). Separation caused a transient increase in cortisol levels on the first (CONT and IS12) and second (IS12) day of separation, compared with a gradual decline from early morning when the sows were still continuously suckling. In IS6 sows, in contrast, the transient rise in cortisol levels after separation at 08:00 hours was observed on the first 3 days and also on day 7 of the IS regime. Cortisol parameters were correlated with peri‐ovulatory characteristics like onset of oestrus, onset of the LH surge and time of ovulation. Onset of the LH surge was delayed in IS6 sows. In conclusion, increase in cortisol levels as a consequence of separation of sows and piglets, is an acute, incidental phenomenon in IS12 and CONT sows, but shows a repeated acute elevation in IS6 sows, possibly placing IS6 sows at a higher risk of influencing peri‐ovulatory processes and developing cystic follicles.
Effects of Matrix Filtration of Low‐Quality Boar Semen Doses on Sperm Quality
Authors: Bussalleu E , Pinart E , Rivera MM , Briz M , Sancho S , Yeste M , Casas I , Fàbrega A , Rigau T , Rodriguez‐Gil JE , Bonet S 
Published: January 2009

ContentsThe aim of this work was to develop a method to enhance the sperm parameters of ejaculates with low sperm quality from Piétrain boars. Seminal doses were filtered through columns of DEAE Sephadex (length 2.5 ± 0.5 cm), CM Sephadex (length 5 ± 0.5 cm), glass wool (length 2 ± 0.5 cm) or glass bead (length 10 ± 0.5 cm), with an exit flow rate of 1 ml/40 s in all cases. For each male, 10 ml of the sperm cell‐rich fraction diluted at 1 : 6 were filtered. Sperm quality was assessed before and after filtration. Sperm morphology, sperm motility and sperm concentration were determined using the computer program sca® 2002 Production, and sperm viability was evaluated by fluorescence multistaining. Osmotic resistance test and hyperosmotic resistance test were used to determine the osmotic resistance of spermatozoa, whereas l‐lactate production estimated the metabolic activity. Results showed a decrease of sperm concentration and osmotic resistance of spermatozoa after filtration in the four matrixes. However, an increase in the frequency of viable spermatozoa with intact acrosome after filtration in glass bead columns and an increase of morphologically normal spermatozoa after filtration in Sephadex CM‐50, glass wool and glass bead columns were observed. Despite the decrease in the frequency of progressive motile spermatozoa, l‐lactate production and mitochondrial sheath integrity maintained constant after filtration. Our findings indicate that column filtration is an effective method to enhance the sperm quality by selecting viable and morphologically normal spermatozoa without altering DNA, plasma membrane, mitochondrial sheath integrity or inducing premature acrosome reaction.