bluuebunny/crossref_metadata_2025_split huggingface dataset:
Choleragen activation of solubilized adenylate cyclase: Requirement for GTP and protein activator for demonstration of enzymatic activity
Authors: Moss Joel , Vaughan Martha 
Published: May 2006

The requirements for choleragen activation of adenylate cyclase [ATP pyrophosphate-lyase (cyclizing), EC 4.6.1.1] were investigated by using an enzyme preparation solubilized with Triton X-100 from an extensively washed brain particulate fraction and partially purified with DEAE-cellulose. Unlike the particulate enzyme, this preparation was not activated after incubation with choleragen plus dithiothreitol, ATP, and NAD. Addition of the purified protein activator of cyclic nucleotide phosphodiesterase and calcium to the partially purified enzyme increased basal activity somewhat, but choleragen activation was minimal. When cyclase was incubated with GTP plus the protein activator (and calcium), choleragen markedly increased the activity 3- to 6-fold. When GppNHp and protein activator were incubated with the cyclase prior to assay, activity was elevated but no effect of choleragen was observed. GTP and GppNHp had relatively small effects on cyclase activity in the absence of protein activator or if they were added directly to the assay. Boiled brain supernatant was consistently more effective than protein activator (plus calcium) and GTP, suggesting that other factors are required for maximal cyclase activity after choleragen treatment.
It appears that the cyclase system is dissociable into several components, all of which may be necessary for optimal regulation of activity. It is probable that one of these is the heat-stable calcium-dependent protein activator of cyclic nucleotide phosphodiesterase and adenylate cyclase that we have found is required along with GTP for demonstration of choleragen activation of partially purified brain adenylate cyclase.
Expression of a high molecular weight cell surface glycoprotein (LETS protein) by preimplantation mouse embryos and teratocarcinoma stem cells
Authors: Zetter Bruce R. , Martin Gail R. 
Published: May 2006

The expression of a high molecular weight cell surface glycoprotein (LETS, fibronectin) by preimplantation mouse embryos as well as cultured teratocarcinoma stem cells was detected by using indirect immunofluorescent staining. When each stage of preimplantation embryonic development was tested for the presence of LETS protein, none was observed on two-cell, four-cell, or eight-cell embryos, or on the morula or the outer cell layer (trophectoderm) of the early or late blastocyst. However, when the inner cell mass was isolated by immunosurgery, positive staining was observed. The intensity of the staining was significantly greater on the inner cell mass isolated from the expanded (day 4) blastocyst than on that from the early (day 3) blastocyst.
Certain established cell lines of teratocarcinoma stem cells (embryonal carcinoma cells) also express cell surface LETS protein. “Nullipotent” (Nulli-SCC-1) as well as pluripotent (PSA 1) embryonal carcinoma cell lines have deposits of LETS protein concentrated in areas of cell-cell contact. In addition, a teratocarcinoma-derived endodermal cell line (PYS) was found to be capable of depositing LETS onto the substratum in a fibrillar network.
Taken together, our results indicate that LETS protein is synthesized at a specific stage of preimplantation mouse embryonic development. In particular, they suggest that LETS protein is a product of the embryonic ectoderm, and that some types of embryonic endoderm are also capable of synthesizing this protein.
Isolation and characterization of purine-nucleoside phosphorylase-deficient T-lymphoma cells and secondary mutants with altered ribonucleotide reductase: Genetic model for immunodeficiency disease
Authors: Ullman Buddy , Gudas Lorraine J. , Clift Shirley M. , Martin David W. 
Published: May 2006

The inherited deficiency of purine-nucleoside phosphorylase (PNPase; purine-nucleoside:orthophosphate ribosyltransferase, EC 2.4.2.1) in humans is associated with a severe deficiency of the T lymphocytes of the immune system. Because of the unsatisfactory nature of previously described model systems, we have selected, cloned, and characterized a mutant mouse T cell lymphoma (S49) completely deficient in PNPase. Of the four substrates of PNPase, only deoxyguanosine at low concentrations is toxic to the PNPase-deficient (NSU-1) cells.
In order to delineate the biochemical processes necessary for the sensitivity of the NSU-1 cells to deoxyguanosine, we have isolated a series of secondary mutants resistant to deoxyguanosine from the PNPase-deficient line. One of these mutants is defective in its ability to transport deoxyguanosine into the cell. A second type of mutant cannot phosphorylate the deoxyguanosine and is totally deficient in deoxycytidine kinase activity. A third type of mutant (NSU-1-dGuo-L) can both transport and phosphorylate deoxyguanosine and accumulates dGTP. However, unlike its parent, NSU-1-dGuo-L does not become depleted of dCTP and TTP when exposed to exogenous deoxyguanosine. This observation is accounted for by the fact that the reduction of CDP to dCDP by the ribonucleotide reductase (ribonucleoside-diphosphate reductase, 2′-deoxyribonucleoside-diphosphate:oxidized-thioredoxin 2′-oxidoreductase, EC 1.17.4.1) of NSU-1-dGuo-L cells is not normally sensitive to feedback inhibition by dGTP.
Thus, in order to exert its toxicity deoxyguanosine must be transported into the cell, be phosphorylated by deoxycytidine kinase, and be accumulated as dGTP. By inhibiting ribonucleotide reductase, dGTP depletes the cell of dCTP and to some extent TTP, thus preventing the synthesis of DNA, a process necessary for any proliferation-dependent function of T cells.
Fostering Multidisciplinary Engagement: Communication Challenges for Social Research on Emerging Digital Technologies
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Authors: Dutton William H. , Carusi Annamaria , Peltu Malcolm 
Published: May 2006

Abstract
There is wide agreement on the value of multidisciplinary social research related to information and communication technologies. This paper provides insights into the dynamics at play in these studies, drawing on an in‐depth analysis of exchanges among an international group of experts from many relevant disciplines who participated in a workshop on research into the social implications of emerging digital technologies. In addition to identifying some distinctive new challenges facing this field, the paper suggests how understanding ways to foster productive engagement in discussing and developing issues and joint work could lead to more useful multidisciplinary partnerships.
Coordinate responses of transcription factors to ecdysone during programmed cell death in the anterior silk gland of the silkworm, Bombyx mori
Authors: Sekimoto T. , Iwami M. , Sakurai S. 
Published: May 2006

AbstractProgrammed cell death (PCD) in Bombyx mori anterior silk glands (ASGs) is triggered by 20‐hydroxyecdysone (20E). We examined the expression profiles and effects of 20E on 11 transcription factor genes in the fifth instar to determine whether they demonstrate the hierarchical control seen in Drosophila PCD. Results indicate that EcR‐A and usp‐2, but not EcR‐B1 or usp‐1, may be components of the ecdysone receptor complex. Up‐regulation of E75A, BHR3, and three BR‐C isoforms, but not E75B, appeared to be associated with the induction of PCD. βFTZ‐F1 was not expressed during PCD execution. Thus, gene control in B. mori ASGs differs from that in Drosophila salivary glands, despite both tissues undergoing PCD in response to 20E at pupal metamorphosis.
The Arabidopsis ARGOS‐LIKE gene regulates cell expansion during organ growth
Authors: Hu Yuxin , Poh Huay Mei , Chua Nam‐Hai 
Published: May 2006

SummaryCell expansion, and its coordination with cell division, plays a critical role in the growth and development of plant organs. However, the genes controlling cell expansion during organogenesis are largely unknown. Here, we demonstrate that a novel Arabidopsis gene, ARGOS‐LIKE (ARL), which has some sequence homology to the ARGOS gene, is involved in this process. Reduced expression or overexpression of ARL in Arabidopsis results in smaller or larger cotyledons and leaves as well as other lateral organs, respectively. Anatomical examination of cotyledons and leaves in ARL transgenic plants demonstrates that the alteration in size can be attributed to changes in cell size rather than cell number, indicating that ARL plays a role in cell expansion‐dependent organ growth. ARL is upregulated by brassinosteroid (BR) and this induction is impaired in the BR‐insensitive mutant bri1, but not in the BR‐deficient mutant det2. Ectopic expression of ARL in bri1–119 partially restores cell growth in cotyledons and leaves. Our results suggest that ARL acts downstream of BRI1 and partially mediates BR‐related cell expansion signals during organ growth.
MHC class I variation associates with parasite resistance and longevity in tropical pythons
Authors: Madsen T. , Ujvari B. 
Published: May 2006

Abstract
Using restriction fragment length polymorphism (RFLP) we identified 26 unique major histocompatibility complex (MHC) genotypes in 104 water pythons. We observed a significant independent association between reduced blood parasite load (Hepatozoon sp.) and python body length/age, presence of a specific RFLP fragment (C-fragment) and the overall number of fragments. The parasite has a negative impact on several python life-history traits such as growth, nutritional status and longevity. Thus, the C-fragment could be considered a ‘good gene’ (a fitness-enhancing genetic element). However, while the number of fragments affected parasite load, the association between level of parasitaemia and fragment number was not linear, and, hence, minimum parasite infection level was achieved at an intermediate number of fragments. Intermediate MHC fragment numbers were also observed among the largest/oldest pythons, suggesting that both a specific fragment and intermediate levels of MHC polymorphism enhanced python longevity. Thus, our results suggest python MHC is subject to both frequency-dependent and balancing selection.
Clinical implication of atypical cells from sputum in patients without lung cancer
Authors: KO Dong Seok , MOON Kyung Chul , CHUNG Doo Hyun , HWANG Yong Il , YOO Chul‐Gyu , KIM Young Whan , HAN Sung Koo , SHIM Young‐Soo , YIM Jae‐Joon 
Published: May 2006

Objective and background:  Atypical—but not definitely malignant—cells in cytological examinations of sputum are usually associated with lung cancers. However, atypical cells are occasionally identified in patients without lung cancer. The aim of this study was to determine the clinical implication of the atypical cells from sputum in patients without lung cancer or other malignancies.Methodology:  All patients with atypical cells observed following cytological examination of sputum on one or more occasion over a 2‐year period in Seoul National University Hospital were enrolled. After exclusion of patients followed up for less than 6 months, their clinical data were reviewed retrospectively.Results:  Among 601 enrolled patients with atypical cells, lung cancers were diagnosed within 30 days of identification of atypical cells in 542 (90.2%) patients. Five out of 59 patients who had no evidence of lung cancer, were subsequently diagnosed with lung cancer or other malignancies following a mean observation of 164 days. In the other 54 patients without subsequent malignancies, the most common respiratory diseases were pneumonia including tuberculosis.Conclusions:  The subsequent development of malignancy in patients with atypical cells in sputum despite a thorough evaluation was rare, and close observation without invasive diagnostic procedures might be simply required in these patients.
Population‐based prospective molecular and conventional epidemiological study of tuberculosis in Hong Kong
Authors: CHAN‐YEUNG Moira , KAM Kai‐man , LEUNG Chi‐chiu , WANG Julie , YEW Wing‐wai , LAM Chak‐wah , TAM Cheuk‐ming 
Published: May 2006

Objective:  To study the transmission of tuberculosis using conventional and molecular epidemiology in Hong Kong.Methods:  All patients with positive sputum culture for Mycobacterium tuberculosis residing on the Island of Hong Kong were recruited from May 1999 to April 2002. The restriction fragment length polymorphism technique was used to determine DNA patterns of isolates of M. tuberculosis using the IS6110 probe, supplemented by pTBN12 as a secondary probe.Results:  One thousand five hundred and fifty‐three of 2337 (66%) of the patients with bacteriologically confirmed tuberculosis had restriction fragment length polymorphism analysis of their M. tuberculosis isolates. Four hundred and fifty‐four (29.2%) patients belonging to 143 clusters were identified; the estimated rate of recent transmission was 20–24%. Significant predictors of clustering included young‐age groups (<40 years) versus those >60 years of age (adjusted odds ratio (OR) 1.96, 95% confidence interval 1.47–2.62), permanent residency versus new or non‐residents (adjusted OR 3.40, 95% 1.84–6.26) and previous default from treatment versus new cases (adjusted OR 6.12, 95% confidence interval 1.82–20.5). Alcohol and drug abuse, history of imprisonment and HIV infection were not significant risk factors for molecular clustering. Of patients belonging to clusters, 5.1% had definite, 5.5% had probable and 24.4% had possible epidemiological link, suggesting casual contact may be responsible for a high proportion of the clustered cases.Conclusion:  One‐fifth to one quarter of the new cases of active tuberculosis in Hong Kong are due to recent transmission. In addition to early diagnosis and successful treatment of all active disease, treatment of latent disease should receive more attention in the control of tuberculosis in Hong Kong.
Comparative analysis of the effects of hubble‐bubble (Sheesha) and cigarette smoking on respiratory and metabolic parameters in hubble‐bubble and cigarette smokers
Authors: AL MUTAIRI Sana S. , SHIHAB‐ELDEEN Aida A. , MOJIMINIYI Olusegun A. , ANWAR Alia Aisha 
Published: May 2006

Objectives and background:  Hazard of smoking tobacco is believed to be minimized by smoking hubble‐bubble (HB) instead of cigarettes. Our aims were to (i) develop an assay for estimating nicotine and cotinine; and (ii) evaluate the effect of smoking on respiratory and metabolic parameters in cigarette and HB smokers.Methods:  Urine samples were collected from 152 volunteer smokers (75 cigarette and 77 HB) as well as from 16 healthy controls. We optimized an HPLC method for the determination of nicotine and cotinine. Subjects were asked to complete a chronic respiratory symptoms questionnaire and to undergo spirometry. Fasting blood samples were collected for the determination of their lipid profile.Results:  The intra‐assay coefficients of variation for nicotine and cotinine were 16.6% and 6.6%, respectively. The mean of cotinine in cigarette smokers (1321.4 ng/mL) was significantly (P = 0.008) higher than the mean cotinine (677.6 ng/mL) in HB smokers. The mean nicotine level in cigarette smokers (1487.3 ng/mL) was significantly (P < 0.0001) higher than the mean nicotine (440.5 ng/mL) in HB smoker. The urinary cotinine and nicotine levels of the control subjects were lower than the detection levels of the assay. The mean high‐density lipoprotein cholesterol was lower in cigarette smokers (0.99 mmol/L) compared with HB smoker smokers (1.02 mmol/L) but this was not significant (P = 0.28). Spirometric values were comparable among the three groups but the chronic respiratory symptoms in the smoking groups appeared at an earlier age in the HB smokers compared with the cigarettes smokers (P < 0.05).Conclusion:  Smoking HB does not reduce the risk of tobacco exposure and it’s potentially harmful metabolites on health.
Flow‐dependent resistance of nasal masks used for non‐invasive positive pressure ventilation
Authors: WINDISCH Wolfram , BUCHHOLT Alexander , STAHL Claudius A. , SORICHTER Stephan , GUTTMANN Josef 
Published: May 2006

Objective and background:  Endotracheal tube resistance is known to be flow‐dependent and this understanding has improved the application of invasive ventilation. However, similar physiological studies on the interface between patients and non‐invasive positive pressure ventilation (NPPV) have not been performed. Therefore, this study was aimed at investigating the resistance of nasal masks used for NPPV.Methodology:  The flow‐dependent pressure drop of the small (S), medium‐small (MS) and medium (M) Contour Nasal Mask (Respironics Inc., Murrysville, PA, USA) was measured with and without a connecting tube (length 18 cm, internal diameter 1.5 cm) in a laboratory study. The resistance was calculated by Rohrer’s equation using the standard least‐squares‐fit technique. The present study explicitly differentiated between the resistance of the nasal mask alone when measured against atmosphere and the additional resistance caused by the nasal mask when airtightly fitted to a model head (interaction with the face).Results:  Higher flow rates resulted in a non‐linearly increasing pressure drop across the interface. This flow‐dependent resistance of the S/MS/M mask was comparably low when not interacting with the face, but increased when interacting with the face. This flow‐dependent resistance of the mask was several‐fold higher when adding the connection tube and tended to be higher during expiration.Conclusion:  There is a non‐linear flow‐dependent pressure drop across the nasal mask which is low and independent of its size, but increases when interacting with the face. The connecting tube is the major determinant of the resistance originating from facial appliances used for NPPV.
Delay period activity of monkey prefrontal neurones during duration‐discrimination task
Authors: Oshio Ken‐ichi , Chiba Atsushi , Inase Masahiko 
Published: May 2006

AbstractEvidence from brain imaging studies has indicated involvement of the prefrontal cortex (PFC) in time perception; however, the role of this area remains unclear. To address this issue, we recorded single neuronal activity from the PFC of two monkeys while they performed a duration‐discrimination task. In the task, two visual cues (a blue or red square) were presented consecutively followed by delay periods and subjects then chose the cue presented for the longer duration. Durations of both cues, order of cue duration [long–short (LS) or short–long (SL)] and order of cue colour (blue–red or red–blue) were randomized on a trial‐by‐trial basis. We found that subjects responded differently between LS and SL trials and that most prefrontal neurones showed significantly different activity during either the first or the second delay period when comparing activity in LS and SL trials. The present result offers new insights into neural mechanisms of time perception. It appears that, during the delay periods, the PFC contributes to implement a strategic process in temporal processing associated with a trial type (LS or SL) such as representation of the trial type, retention of cue information and anticipation of the forthcoming cue.
Cellular and subcellular localization of neurokinin‐1 and neurokinin‐3 receptors in primate globus pallidus
Authors: Lévesque Martin , Parent Rémy , Parent André 
Published: May 2006

AbstractThe primate globus pallidus receives massive innervations from GABAergic striatal neurons that co‐release the neuropeptide substance P (SP). To expand our knowledge regarding SP interaction at pallidal level, we used single and double antigen retrieval methods to study the cellular and subcellular localization of SP and its high‐affinity receptors neurokinin‐1 (NK‐1R) and neurokinin‐3 (NK‐3R) in the globus pallidus of the squirrel monkey (Saimiri sciureus). At the light microscopic level, a large number of neurons and fibers located in both the external (GPe) and internal (GPi) segments of the globus pallidus expressed NK‐1R or NK‐3R immunoreactivity. At the electron microscopic level, both NK‐1R and NK‐3R were mainly associated with intracellular sites or located at extrasynaptic positions on the plasma membrane. Presynaptic axon terminals forming symmetric and asymmetric synapses occasionally contained NK‐1R and NK‐3R. Neurokinin receptors were also observed in a proportion of SP‐immunoreactive axon terminals, but these terminals preferentially expressed NK‐3R. The pattern of distribution of NK‐1R and NK‐3R in GPe and GPi indicates that SP effects at pallidal level are mediated through postsynaptic receptor as well as presynaptic autoreceptors and heteroreceptors. These morphological data suggest that, either alone or in conjunction with GABA, SP could have a wide range of effects at pallidal level. This neuroactive peptide may influence in a significant manner the integration and treatment of neural information that flows through the basal ganglia.
Ancient Israel, Judaism and Christianity in Contemporary Perspective. Essays in Memory of Karl‐Johan Illman – Edited by Jacob Neusner, Alan J. Avery‐Peck, Antti Laato, Risto Nurmela and Karl Gustav Sandelin (eds)
Authors: Bury Benjamin 
Published: May 2006

Book reviewed: Ancient Israel, Judaism and Christianity in Contemporary Perspective. Essays in Memory of Karl‐Johan Illman, Jacob Neusner, Alan J. Avery‐Peck, Antti Laato, Risto Nurmela and Karl Gustav Sandelin (eds), Lanham University Press of America 2006 (0‐7618‐3362‐5), ix + 448 pp., pb $41.00
Cinéma Divinité: Religion, Theology, and the Bible in Film – Edited by Eric S. Christianson, Peter Francis and William Telford (eds)
Authors: Gravett Sandie 
Published: May 2006

Book reviewed: Cinéma Divinité: Religion, Theology, and the Bible in Film, Eric S. Christianson, Peter Francis and William Telford (eds), SCM press 2005 (0‐334‐02988‐0), xvii + 373 pp., pb £19.99
In Defense of Natural Theology: A Post‐Humean Assessment – Edited by James F. Sennett and Douglas Groothuis (eds)
Authors: Anderson Owen 
Published: May 2006

Book reviewed: In Defense of Natural Theology: A Post‐Humean Assessment, James F. Sennett and Douglas Groothuis (eds), Intervarsity Press 2005 (0‐8308‐2767‐6), 336 pp., pb $13.00
Loves Me, Loves Me Not: The Ethics of Unrequited Love – Laura A. Smit
Authors: McCarthy David M. 
Published: May 2006

Book reviewed: Loves Me, Loves Me Not: The Ethics of Unrequited Love, Laura A. Smit, BakerAcademic 2005 (0‐8010‐2997‐X), 265 pp., pb $18.99
Harvesting Martin Luther’s Reflections on Theology, Ethics, and the Church – Edited by Timothy J. Wengert (ed.)
Authors: Cross Richard 
Published: May 2006

Book reviewed: Harvesting Martin Luther’s Reflections on Theology, Ethics, and the Church, Timothy J. Wengert (ed.), Lutheran Quarterly Books, William B. Eerdmans Publishing Company 2004 (8‐028‐2486‐2), xiv + 260 pp., £21.99
World without End: Christian Eschatology from a Process Perspective – Edited by Joseph A. Bracken (ed.)
Authors: Reed Esther D. 
Published: May 2006

Book reviewed: World without End: Christian Eschatology from a Process Perspective, Joseph A. Bracken (ed.), Eerdmans 2005 (0‐8028‐2811‐6), ix + 232 pp., hb $30.00/£18.95