bluuebunny/crossref_metadata_2025 huggingface dataset:
Tissue selective localization of oral cimetropium bromide to muscarinic receptors in colonic smooth muscle
Authors: DE CONTI L. , GIACOMETTI S. , SCHERINI E. , BERNOCCHI G. , LADINSKY H.
Published: August 2010

AbstractThe time‐related distribution and muscarinic receptor binding of orally administered cimetropium, a quaternary ammonium antimuscarinic drug, in longitudinal smooth muscle of intestinal segments and other bodily tissues of the rat was investigated in parallel with atropine in an in‐vivo binding study combined with autoradiograpic imaging. Unlike the binding of the quaternary drug in duodenum, jejunum and ileum, which decreased with time, the binding of the drug to colonic smooth muscle increased with time over a 15‐h period. Binding was absent in the right atrium and minor and temporary in submandibular glands. The tissue distribution of (3H)cimetropium 24 h after oral administration mirrored the binding data. Micro‐autoradiographic imaging performed 24 h after oral administration of (14C)cimetropium showed silver grains to be distributed in highest density in colonic tissues, i.e. the smooth muscles, blood vessels (mainly venulesj and the deep mucosal glands; and in hepatocytes. Negligible grain densities were seen in heart, exocrine glands and other bodily tissues. The results indicate that oral cimetropium, differently from atropine, accumulates selectively in colon–and binds specifically there to muscarinic receptors in smooth muscle–by a mechanism more reflective of transit along the enterai tract, and local uptake and elimination, than absorption in the upper gastrointestinal region.
The non‐specific induction of mastocytosis in rat intestinal muscle
Authors: VERMILLION D. L. , COLLINS S. M.
Published: August 2010

We examined the effects of bowel manipulation on mast‐cell number and function in the rat. Mast cells were assessed histologically and by their ability to induce muscle contraction. Anaesthesia or abdominal incision did not alter mast‐cell number. However, laparotomy plus brief exteriorization of jejunal segments significantly increased mast‐cell number. Applying saline to the serosal surface by swab or droplet application increased mast‐cell number 16‐ and 3‐fold, respectively. Saline swabbing of jejunal segments from rats previously infected with Trichinella significantly reduced mast‐cell number. Functional integrity of mast cells was illustrated by muscle contraction in vitro following compound 48/80 or antigen and inhibition of cromoglycate. Serosal application of compound 48/80 in vivo increased mast‐cell number. This increase in mast‐cell number by compound 48/80 or by saline was prevented by prior treatment with cromoglycate. These data suggest that mast‐cell degranulation underlies the manipulation‐induced mastocytosis in gut muscle.
Effect of calcium antagonists on acetylcholine‐induced contractions in longitudinal smooth muscle strips from sheep duodenum
Authors: de PEDRO M.J. , PLAZA M. A. , ARRUEBO M. P. , MURILLO M. D.
Published: August 2010

The effect of several calcium antagonists on acetylcholine‐induced contractions has been examined in longitudinal smooth muscle strips from sheep duodenum. Contractions induced by 10−5M acetylcholine were inhibited up to 65% in Ca2+‐free solution and were blocked in the absence of extracellular Ca2+plus 1 mM EGTA; 10 mM lanthanum reduced acetylcholine‐induced contractions by 97%: 105mverapamil and W−4mnifedipine reduced contractions by 58 and 42%, respectively, but sodium nitroprusside did not modify these responses: 10−4mtrifluoperazine inhibited acetylcholine‐induced responses by 75%: 10−2mcaffeine produced a contraction; 2 mmprocaine antagonized acetylcholine responses by 85%. We suggest that acetylcholine‐induced contractions were mediated by extracellular Ca2+that enters through a potential‐dependent Ca2+channel by intracellular Ca2+release, probably from sarcoplasmatic reticulum because procaine inhibits the response.
Effect of cholecystokinin octapeptide and somatostatin on the mechanical and electrical activity of the colon of conscious dogs
Authors: ATANASSOVA E. , BOCHEVA A. , MILENOV K.
Published: August 2010

Intraluminal pressure and electrical activity of the colon of conscious dogs were recorded using silver bipolar electrodes and a pressure transducer. Two phases in the mechanogram of the transverse colon were observed: a quiescent phase (lack of contractions) lasting 12.05 ± 0.54 min and a contractile phase lasting 14.46 ± 0.88 min. The electrical activity was characterized by a quiescent phase (only slow waves in the electrogram) with a duration of 13.55 ± 1.73 min. Groups of spike potentials bursting in the rhythm of the slow waves appeared during the activity phase lasting 15.60 ± 2.02 min. Cholecystokinin octapeptide (CCK8) (10–20 ng/kg i.v.) significantly increased the duration of 1–3 active phases and shortened the duration of the quiescent phases. The percentage of slow waves with spike potentials during the active phase in the electro‐gram increased. Colonic contractions also increased, i.e. CCK8 evoked an enhanced motility of the colon. Somatostatin (1–2 μg/kg i.v.) increased by two to three times the duration of the quiescent phases. Atropine (50–100 μg/kg i.v.) or somatostatin (1–2 μg/kg i.v.) inhibited both the spontaneous and the CCK8‐induced colonic motility. It is suggested that the inhibitory effect of somatostatin on spontaneous and CCAV induced colonic activity in conscious dogs is mediated by a decrease in cholinergic neurotransmission.
Psyche, personality and gut functions
Authors: STACHER G.
Published: August 2010

Psychological factors are widely held to be important for the orderly function of the gastrointestinal tract as well as for the development and course of disorders affecting the gut. Evidence supporting these assumptions is scarce, although it has become clear that intestinal functions are influenced by the state of central nervous activation, i.e. by satiation, relaxation and sleep as well as hunger, tension and rage. Freud assumed that the accumulation of an unabreacted quota of affect induced defence or repression and a conversion of emotion into bodily symptoms. Subsequently, disorders such as globus sensation, diffuse oesophageal spasm and ‘cardiospasm’ were viewed as conversion symptoms. Other concepts claimed an aetiological role of specific conflicts, certain affective states and ‘inappropriate perpetuations of organ reactions adaptive to, or protective against, some stress in human life’. However, these and other psychosomatic concepts could not be verified. Conversely, an illness exacerbation may precipitate a disruption in a patient's adjustment to his/her environment and interfere with his/her ability to fight the disease. Psychotherapeutic interventions may help patients to cope with their illness and its consequences and possibly alter the course of disease. Psychosocial factors may determine a patient's reactions to, and handling of, a disease and thus should not escape the physician's attention.
Identification of mechanisms for duodenal contraction induced by tachykinins in the rat
Authors: KIM Y. C. , HELLSTRÖM P. M.
Published: August 2010

Mechanisms for contractile effects of tachykinins on muscle strips of rat duodenum were studied using substance P (SP), neurokinin A (NKA), neurokinin B (NKB) and neuropeptide K (NPK), and the tachykinin analogues SP methyl ester (SPME), Nle10‐NKA(4–10) (NleNKA) and senktide (SENK) selective for neurokinin (NK)‐1, NK‐2 and NK‐3 receptors, respectively. NK receptors responsible for smooth muscle contraction were identified using selective ligands to protect NK receptors combined with inactivation of residual receptors with N‐ethylmaleimide. Tachykinins (10−9to 10−5M) caused dose‐related contractions of the muscle strips. The order of potency of native tachykinins was NKA > NKB > SP > NPK in circular, and NKB > NKA > NPK > SP in longitudinal muscle, whereas that of selective tachykinin analogues was SENK > NleNKA > SPME. NKA, NleNKA and SENK were equieffective as acetylcholine, whereas SP, SPME, NKB and NPK were less effective. Spantide decreased the sensitivity to all tachykinin analogues. Atropine reduced the sensitivity to SENK only, whereas hexamethonium reduced the sensitivity to SENK and SPME, but not to NleNKA. Selective receptor protection with SPME, NleNKA or SENK protected contractions induced by SPME, NleNKA and SENK, respectively. Responses to tachykinin analogues were reduced in Ca2+‐free medium. Thus, NKA is suggested to be the dominating tachykinin to stimulate contraction of the rat duodenum via NK receptors coupled to Ca2+‐dependent signal transduction pathways. Of the receptors available, the NK‐1 subtype involves a nicotinic transmission step, and the NK‐3 subtype also a muscarinic step, whereas the NK‐2 receptor subtype is not dependent on cholinergic mechanisms.
The relationship between gastric pH and the emptying of solid, semisolid and liquid meals
Authors: CLARK G. W. B. , JAMIESON I. R. , HINDER R. A. , POLISHUK P. V. , DEMEESTER T. R. , GUPTA N. , CHENG S.C.
Published: August 2010

The effect of three different meal constituents, solid, semisolid and liquid, on gastric pH, recorded in the proximal and distal stomach, was evaluated in a prospective study of 20 normal volunteers. The solid and liquid were ingested together as one meal and the semisolid as another. Simultaneous recordings of the rate of gastric emptying of the isotopically labelled meal constituents and the gastric pH were made. The rate of gastric emptying was more rapid for the liquid and semisolid constituents (t1/2= 35.6, range 9.8–103.3 min and 47.4, range 33.5–120 min, respectively) than for the solid meal constituent (t1/2= 72.0, range 45.0–103.8 min), P < 0.01. Both the combined meal of solid and liquid and the semisolid meal produced a higher pH response in the proximal stomach than in the distal stomach (5.2, range 2.4–6.1 vs 2.9, range 0.8–5.3 and 5.9, range 4.3–6.6 vs 4.3, range 1.1–5.9), P < 0.01. There were significant correlations between the rate of gastric emptying of all three meal constituents and the decline phase in the gastric pH recorded at both the proximal and distal probes, P < 0.01 (Pearson's correlation). The strongest correlations were found between the rate of gastric emptying and the gastric pH recorded in the proximal stomach. The decline phase of gastric pH followed the emptying of semisolid more closely than the emptying of either solid or liquid.
Effects of nutrient infusions into rat small intestinal isolated loops on gastrointestinal transit time
Authors: BROWN N. J. , RUMSEY R. D. E. , READ N. W.
Published: August 2010

Abstract Studies in the dog have shown that when equicaloric nutrients are infused into the distal small intestine, glucose is the most potent inhibitor of proximal small intestinal motility. Studies in man and rat have shown lipid to be the most potent inhibitor of gastrointestinal motility, but the nutrients were not infused at equicaloric loads. These studies aimed to investigate the effect of infusing nutrients (Intralipid 20%, protein 8g/100 ml, glucose 50 mM, rice starch 5 g/ 100 ml), either alone or in combination, into isolated jejunal or ileal loops on stomach to caecum transit time (SCTT) to establish whether regional control of gastrointestinal motility by specific nutrients exists. The effects of infusing equicaloric nutrients (0.2 and 2 kcal) into the ileal loops on SCTT were also investigated. SCTT was significantly delayed when Intralipid (P < 0.001) was infused into ileal loops and when glucose was infused into jejunal loops (P < 0.01). Infusing protein with lipid abolished the effect of ileal lipid on SCTT, but infusing glucose with lipid still produced a significant delay in SCTT of the meal. Infusing either lipid or protein at 2 kcal delayed SCTT, but equicaloric loads of glucose had no effect. These results suggest both species and regional differences in the control of gastrointestinal motility.
Loxiglumide abolishes the effects of intraduodenal oleic acid on gastric motility and emptying in the pig
Authors: ANVARI M. , MALBERT C.‐H. , HOROWITZ M. , JAMIESON G. G.
Published: August 2010

AbstractThe role of cholecystokinin in mediating the effects of intraduodenal fat infusion on gastric motility and gastric emptying and the pattern of transpyloric flow was evaluated in conscious pigs. Concurrent measurements of antropyloroduodenal motility with an eight‐channel sleeve/sidehole catheter, transpyloric flow and gastric emptying after instillation of 1000 ml of saline into the stomach, were made during intraduodenal infusion of either normal saline or oleic acid at 5 ml min−1. Studies with intraduodenal oleic acid were performed with and without intravenous infusion of loxiglumide (30 mg kg−1intravenous bolus 15 min before intraduodenal oleic acid, followed by intravenous infusion of 10 mg kg−1h−1), Intraduodenal oleic acid was associated with stimulation of isolated pyloric pressure waves (P < 0.05), inhibition of antral pressure waves (P < 0.05), reduced pulsatile transpyloric flow (P < 0.05) and retardation of gastric emptying (P < 0.05). when compared to intraduodenal saline. Loxiglumide prevented retardation of gastric emptying by intraduodenal oleic acid (P < 0.05), and maintained it at values that were not significantly different from saline. After loxiglumide there were more antral pressure waves (P < 0.05) and less isolated pyloric pressure waves (P < 0.05) when compared to oleic acid.

These results indicate that the effects of intraduodenal oleic acid on gastric and pyloric motility, and gastric emptying are largely mediated by CCK‐dependent mechanisms.
Mosapride citrate (AS‐4370), a new gastroproltinetic agent, is a partial 5‐HT4receptor agonist in the gut
Authors: YOSHIDA N. , ITO T.
Published: August 2010

AbstractWe examined the possible involvement of 5‐HT4receptors in the gastroprokinetic effects of mosapride citrate (AS‐4370). In isolated longitudinal muscle myenteric plexus (LMMP) preparations from the guinea‐pig ileum, mosapride, cisapride, zacopride and metoclopramide enhanced electrically evoked contractions with EC50values of 74.2, 32.2, 50.3 and 1047.4 nM, respectively. The maximal increases in the amplitude of the contractions caused by mosapride, cisapride, zacopride and metoclopramide were 58, 78, 100 and 92% of those caused by 5‐HT, respectively. The enhancing effect of mosapride was non‐surmountably antagonised by high concentrations of tropisetron (10−‐7–3 ± 10−‐6M), but not by methysergide (10−‐6M) or ondansetron (10−‐6M). In the ileal LMMP preparations, mosapride, cisapride, zacopride and tropisetron had an inhibitory effect related to concentration on the 5‐HT (3 ± 10−‐7M) induced contractions with IC50values of 0.59, 0.71, 0.55 and 7.9 μM, respectively. Mosapride (10−‐8‐−10−‐5M) alone, unlike cisapride and zacopride, did not cause contraction in the ileal LMMP preparations. These results suggest that mosapride is a partial 5‐HT4receptor agonist and possesses 5‐HT4receptor antagonist activity at high concentrations. In conscious dogs with force transducers implanted, mosapride (I mg kg−1, i.v.) enhanced the antral motor activity in the postprandial state, and this enhancement was clearly antagonised by a high dose of tropisetron (10 mg kg−1h−1, i.v. infusion) that did not affect basal motor activity, indicating the involvement of 5‐HT4receptors in the in vivo gastroprokinetic effect of mosapride.
Comparison of simultaneous recordings of human colonic contractions by manometry and a barostat
Authors: VON DER OHE M. R. , HANSON R. B. , CAMILLERI M.
Published: August 2010

Abstract Our hypothesis was that manometry in the colon was less sensitive than the electronic barostat in detection of colonic contractions. In ten healthy volunteers, we have characterised the pressure activity and tone of the colon by means of combined multilumen manometry and a barostatic balloon that was infinitely compliant, conformed to the colon's inner wall, and was clamped at a constant ‘operating’ pressure throughout the study. A computer program separated indices of the colon's motor function detected by the barostat: a baseline volume and phasic volume events. The barostat detects on average 70% more phasic pressure events than manometric sideholes located 2 em proximal to 7 cm distal to the balloon. Manometry becomes less sensitive than the barostat when the colonic diameter exceeds 5.6 em. The barostat detects on average 90% of all propagated and non‐propagated (>30 mmHg) manometric peaks. The baseline volume changes significantly after the ingestion of a 1000‐kcal meal, consistent with an increment in colonic tone, undetected by manometry. A combined barostat—manometry assembly appears to be preferable to manometry alone in the intraluminal evaluation of human colonic pressure activity and tone.
The circuitry of the enteric nervous system
Authors: FURNESS J. B. , BORNSTEIN J. C. , POMPOLO S. , YOUNG H. M. , KUNZE W. A. A. , KELLY H.
Published: August 2010

Abstract A brief account of the aquisition of knowledge of the enteric nervous system and the ways in which technological developments have contributed to analysis of the reflex circuits is presented. The review concentrates on the motility controlling circuits in the small intestine of the guinea‐pig, where much more is known than for any other region or species. In this region, the basic circuit is known. Primary sensory neurons connect monosynaptically to motor neurons, and also make connections via chains of interneurons, which in turn provide outputs to the motor neurons. The ascending excitatory and descending inhibitory reflexes are manifested through these circuits. Sufficient details of the functions and connections of all neuron classes are available to permit activity in the reflex pathways to be realistically simulated in a computer model, which is briefly described.
Volume estimation of the gastric antrum and the gallbladder in patients with non‐ulcer dyspepsia and erosive prepyloric changes, using three‐dimensional ultrasonography
Authors: HAUSKEN T. , THUNE N. , MATRE K. , GILJA O. H. , ØDEGAARD S. , BERSTAD A.
Published: August 2010

Abstract Background: Two‐dimensional ultrasonography has shown a widened gastric antrum in patients with non‐ulcer dyspepsia (NUD) and erosive prepyloric changes (EPC).

Methods: In this study, volumes of gastric antrum and gallbladder were estimated with three‐dimensional (30) ultrasonography before and after ingestion of 500 ml meat soup in 17 NUD with EPC patients and in 18 healthy subjects. A mechanical ultrasound scanner, coupled to a stepping motor, tilted the transducer through an angle of 51° or 88° while recording a total of 95 or 81 images, respectively. Volume estimation was performed digitally after interactive manual contour tracing and organ reconstruction in three dimensions.

Results: Antral volumes were larger in NUD patients than in healthy controls (P = 0.001). Fasting gallbladder volumes were similar in the two groups. Postprandial antral filling was more pronounced in patients than in healthy subjects (P = 0.02). whereas gallbladder emptying was more pronounced in healthy subjects than in patients (P = 0.05). The soup induced dyspeptic symptoms in 15 NUD patients, but only had this effect in two healthy subjects (P < 0.001).

Conclusion: Patients with NUD and EPC are characterized by abnormal antral filling, reduced gallbladder emptying, and dyspeptic symptoms in response to ingestion of meat soup.
In vivo muscle activity and epithelial function in the rabbit distal colon during experimental colitis
Authors: GOLDHILL J. M. , PERCY W. H. , DONOVAN V. , JOSEPH I. , ZHAO L. , BURAKOFF R.
Published: August 2010

Abstract The present in vivo study was conducted to investigate contractile activity and epithelial electrolyte transport in an inflammatory state during experimental colitis in the rabbit. Intrarectal administration of trinitrobenzenesulphonic acid (TNBS) induced a colitis‐like inflammation in the distal colon. Under basal conditions, TNBS evoked irregular patterns of contractions in 40% of treated animals, but total contractility and transmural potential difference were not significantly altered by this treatment. Contractile activity and transmural potential difference were increased by luminal perfusion with phosphate buffered saline in control, but not in TNBS‐treated animals. It was concluded that the inflamed colon does not respond normally to luminal stimulation and that this may contribute to the pathophysiology of inflammatory bowel disease (IBD).
Postcibal secretory and symptomatic responses to increased intragastric pressure
Authors: SAPERAS E. , AZPIROZ F. , CUCALA M. , RODRIGUEZ R. , MALAGELADA J.‐R.
Published: August 2010

Abstract The mechanical and secretory factors in the stomach that may be implicated in the production of symptoms are still poorly understood. To determine whether symptoms in response to postcibal gastric distention are associated with increased acid secretion, the relationship between symptoms, acid secretion and intragastric pressure in healthy subjects was investigated. Perception (by a 0–6 score questionnaire) and the gastric secretory response to a glucose test meal (by intragastric titration) was quantified either at low (2 mmHg) or at high (8 mmHg) intragastric pressure levels, maintained by feedback regulation of the air volume within a gastric bag using an electronic barostat. Low intragastric pressure produced a small gastric expansion (87 ± 26 ml; mean ± SE) that was largely unperceived (score 0.7 ± 0.5). High intragastric pressure did not increase acid secretion (15 ± 3 mEq h‐1 vs 16 ± 3 mEq h‐1 at low pressure), but produced symptomatic perception (score 2.5 ± 0.7) related to a marked gastric expansion (521 ± 92 ml; P < 0.05 vs low pressure for both). It was concluded that postcibal gastric hypertension induces symptoms without affecting the gastric acid secretory response to the meal.
Does in utero exposure to synthetic glucocorticoids influence birthweight, head circumference and birth length? A systematic review of current evidence in humans
Authors: Ali Khan Anokhi , Rodriguez Alina , Kaakinen Marika , Pouta Anneli , Hartikainen Anna‐Liisa , Jarvelin Marjo‐Ritta
Published: August 2010

Ali Khan A, Rodriguez A, Kaakinen M, Pouta A, Hartikainen A‐L, Jarvelin M‐R. Does in utero exposure to synthetic glucocorticoids influence birthweight, head circumference and birth length? A systematic review of current evidence in humans. Paediatric and Perinatal Epidemiology 2010.

Synthetic glucocorticoids are the mainstay treatment for stimulating lung maturation in threatened preterm delivery. Animal studies suggest that in utero exposure to glucocorticoids leads to a reduction in birth size. Smaller birthweight has been associated with higher risk of many chronic diseases. Therefore, the authors undertook a systematic review of human studies examining the association between synthetic glucocorticoid treatment and birth size. Medline, EMBASE, PubMed, Cochrane, Google scholar and Institute of Life Science databases were searched for studies published between 1978 and 2009 investigating the association between synthetic glucocorticoids and birthweight, head circumference, birth length and ponderal index. All studies controlling for gestational age were examined. Seventeen studies were included in the analysis. Nine out of 17 studies reported a reduction in birthweight (range 12–332 g), five of nine a reduction of head circumference (range 0.31–1.02 cm) and two of four a reduction of 0.8 cm in birth length. Despite methodological inconsistencies and limitations that impede clear conclusions, the evidence suggests an association between in utero exposure to synthetic glucocorticoids and reduced birth size.
Membrane localization of a rice calcium‐dependent protein kinase (CDPK) is mediated by myristoylation and palmitoylation
Authors: Martín Mariana L. , Busconi Liliana
Published: August 2010

Calcium‐dependent protein kinases (CDPKs), the most abundant serine/threonine kinases in plants, are found in various subcellular localizations, which suggests that this family of kinases may be involved in multiple signal transduction pathways. A complete analysis to try to understand the molecular basis of the presence of CDPKs in various localizations in the cell has not been accomplished yet. It has been suggested that myristoylation may be responsible for membrane association of CDPKs. In this study, we used a rice CDPK, OSCPK2, which has a consensus sequence for myristoylation at the N‐terminus, to address this question. We expressed wild‐type OSCPK2 and various mutants in different heterologous systems to investigate the factors that affect its membrane association. The results show that OSCPK2 is myristoylated and palmitoylated and targeted to the membrane fraction. Both modifications are required, myristoylation being essential for membrane localization and palmitoylation for its full association. The fact that palmitoylation is a reversible modification may provide a mechanism for regulation of the subcellular localization. OSCPK2 is the first CDPK shown to be targeted to membranes by an src homology domain 4 (SH4) located at the N‐terminus of the molecule.
MADS‐box gene evolution beyond flowers: expression in pollen, endosperm, guard cells, roots and trichomes
Authors: Alvarez‐Buylla Elena R. , Liljegren Sarah J. , Pelaz Soraya , Gold Scott E. , Burgeff Caroline , Ditta Gary S. , Vergara‐Silva Francisco , Yanofsky Martin F.
Published: August 2010

MADS‐box genes encode transcriptional regulators involved in diverse aspects of plant development. Here we describe the cloning and mRNA spatio‐temporal expression patterns of five new MADS‐box genes from Arabidopsis: AGL16, AGL18, AGL19, AGL27 and AGL31. These genes will probably become important molecular tools for both evolutionary and functional analyses of vegetative structures. We mapped our data and previous expression patterns onto a new MADS‐box phylogeny. These analyses suggest that the evolution of the MADS‐box family has involved a rapid and simultaneous functional diversification in vegetative as well as reproductive structures. The hypothetical ancestral genes had broader expression patterns than more derived ones, which have been co‐opted for putative specialized functions as suggested by their expression patterns. AGL27 and AGL31, which are closely related to the recently described flowering‐time gene FLC (previously AGL25), are expressed in most plant tissues. AGL19 is specifically expressed in the outer layers of the root meristem (lateral root cap and epidermis) and in the central cylinder cells of mature roots. AGL18, which is most similar in sequence to the embryo‐expressed AGL15 gene, is expressed in the endosperm and in developing male and female gametophytes, suggesting a role for AGL18 that is distinct from previously characterized MADS‐box genes. Finally, AGL16 RNA accumulates in leaf guard cells and trichomes. Our new phylogeny reveals seven new monophyletic clades of MADS‐box sequences not specific to flowers, suggesting that complex regulatory networks involving several MADS‐box genes, similar to those that control flower development, underlie development of vegetative structures.
Na+/myo‐inositol symporters and Na+/H+‐antiport in Mesembryanthemum crystallinum
Authors: Chauhan Sanjay , Forsthoefel Nancy , Ran Yingquing , Quigley Francoise , Nelson Donald E. , Bohnert Hans J.
Published: August 2010

Mitr1 and Mitr2 from Mesembryanthemum crystallinum (common ice plant) are members of a family of genes homologous to H+[or Na+]/myo‐inositol symporters (ITRs), not previously studied in plants. MITR1 complemented an Itr1‐deficient yeast strain. Mitr1 is strongly expressed in roots, moderately in stems, and weakly in leaves. Its transcripts increased in all organs, most dramatically in roots, under salinity stress. Mitr2 constitutes a rare transcript, slightly upregulated by salt stress in leaves only. Mitr1 transcripts are present in all cells in the root tip, but become restricted to phloem‐associated cells in mature roots. Peptide antibodies against the two proteins indicated the presence of MITR1 in all organs and of MITR2 in leaves. Both are located in the tonoplast. MITR1 acts in removing sodium from root vacuoles, correlated with findings of low root sodium, while leaf vacuoles accumulate sodium in the ice plant. Up‐regulation in leaves and stems is also found for Na+/H+‐antiporter (Nhx‐type) transcripts. Under comparable stress conditions, Nhx‐and Itr‐like transcripts in Arabidopsis were regulated differently. In the ice plant, co‐ordinate induction of Na+/H+‐antiporters and Na+/myo‐inositol symporters transfers sodium from vacuoles in root cells into the leaf mesophyll as a halophytic strategy that lowers the osmotic potential. The tissue‐specific differential expression of Itr‐ and Nhx‐type transcripts suggests that the vacuolar sodium/inositol symporters function to reduce sodium amounts in cells of the root and vascular tissue, while sodium/proton antiporters in leaf tissues function to partition sodium into vacuoles for storage.
Misfolding and aggregation of vacuolar glycoproteins in plant cells
Authors: Sparvoli Francesca , Faoro Franco , Daminati M. Gloria , Ceriotti Aldo , Bollini Roberto
Published: August 2010

Phaseolin and lectin‐related polypeptides, the abundant oligomeric glycoproteins of bean seeds, are synthesized on the endoplasmic reticulum (ER) and then transported to the storage vacuole via the Golgi apparatus. Glycosylation and folding are among the major modifications these proteins undergo in the ER. Although a recurrent role of N‐glycosylation is on protein folding, in previous studies on common bean (Phaseolus vulgaris) seeds we demonstrated that the oligosaccharide side‐chains are not required for folding, intracellular transport and activity of storage glycoproteins. We show here that in lima bean (Phaseolus lunatus), incubation of the developing cotyledon with tunicamycin to prevent glycosylation has a dramatic effect on the intracellular transport of the storage glycoproteins. When lacking their glycans, phaseolin and lectin‐related polypeptides misfold and are retained in the ER as mixed aggregates to which the chaperone BiP irreversibly associates. The lumen of the ER becomes enlarged to accommodate the aggregated polypeptides. Intracellular transport of legumin, a naturally unglycosylated storage protein, is mostly unaffected by the inhibitor, indicating that the observed phenomenon specifically occurs on glycoproteins. Furthermore, recombinant lima bean phaseolin synthesized in tobacco protoplasts is also correctly folded and matured in the presence of tunicamycin. To our knowledge, this is the first report that describes in detail the block of intracellular transport of vacuolar glycoproteins in plant cells due to aggregation following glycosylation inhibition.
A pea homologue of human DNA helicase I is localized within the dense fibrillar component of the nucleolus and stimulated by phosphorylation with CK2 and cdc2 protein kinases
Authors: Tuteja Narendra , Beven Alison F. , Shaw Peter J. , Tuteja Renu
Published: August 2010

DNA helicases catalyse the transient opening of duplex DNA during nucleic acid transactions. Here we report the isolation of a second nuclear DNA helicase (65 kDa) from Pisum sativum (pea) designated pea DNA helicase 65 (PDH65). The enzyme was immunoaffinity purified using an antihuman DNA helicase I (HDH I) antibody column. The purified PDH65 showed ATP‐ and Mg2+‐dependent DNA and RNA unwinding activities, as well as ssDNA‐dependent ATPase activity. The direction of DNA unwinding was 3′ to 5′ along the bound strand. Antibodies against HDH I recognized the purified PDH65, and immunodepletion with these antibodies removed the DNA and RNA unwinding and ATPase activities from purified preparations of PDH65. The DNA and RNA unwinding activities were upregulated after phosphorylation of PDH65 with CK2 and cdc2 protein kinases. By incorporation of BrUTP into pea root tissue, followed by double immunofluorescence labelling and confocal microscopy, PDH65 was shown to be localized within the dense fibrillar component of pea root nucleoli in the regions around the rDNA transcription sites. These observations suggest that PDH65 may be involved both in rDNA transcription and in the early stages of pre‐rRNA processing.
Ectopic expression of ABI3 gene enhances freezing tolerance in response to abscisic acid and low temperature in Arabidopsis thaliana
Authors: Tamminen Ilkka , Mäkelä Pirjo , Heino Pekka , Palva E. Tapio
Published: August 2010

The plant hormone abscisic acid (ABA) regulates several physiological and developmental processes in plants, including stress adaptation and seed maturation. ABA‐mediated processes appear to be central in plant cold acclimation and expression of cold acclimation‐related genes. Ectopic expression of ABI3 encoding a seed‐specific transcriptional activator confers on Arabidopsis vegetative tissues the ability to accumulate seed‐specific transcripts in response to ABA, and also influences some ABA‐mediated vegetative responses. In the present study we characterized the effect of ectopic expression of ABI3 on cold acclimation and development of freezing tolerance in Arabidopsis. We first determined the effect of ABI3 on ABA‐induced expression of cold acclimation‐related genes. Expression of ABI3 increased the ABA‐induced accumulation of transcripts for several ABA/cold/drought‐responsive genes such as RAB18 and LTI78. Enhanced expression of these genes was evident even after transient application of ABA, and the enhanced expression was correlated with increased freezing tolerance in ABI3 transgenic plants. Ectopic expression of ABI3 also appeared to modulate low temperature‐induced freezing tolerance. The ABI3 transgenic plants acclimated faster than the wild‐type plants, and the maximum tolerance obtained was significantly higher. These data showed that lower levels of ABA were needed to trigger the expression of the genes and to maintain the freezing‐tolerant state in the ABI3 transgenic plants, and indicate that ectopic expression of ABI3 leads to enhanced responsiveness to ABA. The ectopic expression of ABI3 could provide a new strategy for engineering plant stress tolerance.
Technical Advance: A novel technique for the sensitive quantification of acyl CoA esters from plant tissues
Authors: Larson Tony R. , Graham Ian A.
Published: August 2010

We report a novel, highly sensitive and selective method for the extraction and quantification of acyl CoA esters from plant tissues. The method detects acyl CoA esters with acyl chain lengths from C4 to C20 down to concentrations as low as 6 fmol in extracts. Acyl CoA esters from standard solutions or plant extracts were derived to their fluorescent acyl etheno CoA esters in the presence of chloroacetaldehyde, separated by ion‐paired reversed‐phase high‐performance liquid chromatography, and detected fluorometrically. This derivitization procedure circumvents the selectivity problems associated with previously published enzymatic methods, and methods that rely on acyl chain or thiol group modification for acyl CoA ester detection. The formation of acyl etheno CoA esters was verified by mass spectrometry, which was also used to identify unknown peaks from chromatograms of plant extracts. Using this method, we report the composition and concentration of the acyl CoA pool during lipid synthesis in maturing Brassica napus seeds and during storage lipid breakdown in 2‐day‐old Arabidopsis thaliana seedlings. The concentrations measured were in the 3–6 µm range for both tissue types. We also demonstrate the utility of acyl CoA profiling in a transgenic B. napus line that has high levels of lauric acid. To our knowledge, this is the first time that reliable estimates of acyl CoA ester concentrations have been made for higher plants, and the ability to profile these metabolites provides a valuable new tool for the investigation of gene function.
Nicotianamine synthase gene expression differs in barley and rice under Fe‐deficient conditions
Authors: Higuchi Kyoko , Watanabe Shunsuke , Takahashi Michiko , Kawasaki Shinji , Nakanishi Hiromi , Nishizawa Naoko K. , Mori Satoshi
Published: August 2010

Nicotianamine (NA) is an intermediate in the biosynthetic pathway of the mugineic acid family phytosiderophores (MAs), which are crucial components of the iron acquisition apparatus of graminaceous plants. In non‐graminaceous plants, NA is thought to be an essential chelator for metal cation homeostasis. Thus NA plays a key role in Fe metabolism and homeostasis in all higher plants. Nicotianamine synthase (NAS, EC 2.5.1.43) catalyzes the trimerization of S‐adenosylmethionine to form one molecule of NA. Barley, a plant that is resistant to Fe deficiency, secretes large amounts of MAs, whereas rice, a plant that is susceptible to Fe deficiency, secretes only small amounts. In this study we isolated a genomic fragment containing HvNAS1 from barley and three rice cDNA clones, osnas1, osnas2 and osnas3, from Fe‐deficient rice roots. We also isolated a genomic fragment containing both OsNAS1 and OsNAS2. In contrast to barley, in which Fe deficiency induces the expression of NAS genes only in roots, Fe deficiency in rice induced NAS gene expression in both roots and chlorotic leaves. The amounts of endogenous NA in both the roots and leaves were higher than in barley. We introduced barley genomic DNA fragments containing HvNAS1 with either 9 or 2 kb of the 5′‐flanking region into rice, using Agrobacterium‐mediated transformation. Fe deficiency induced HvNAS1 expression in both roots and leaves of the transgenic rice, as occurs with rice NAS genes. Barley and rice NAS genes are compared in a discussion of alteration of the NAS genes during adaptation to Fe deficiency.
DFL1, an auxin‐responsive GH3 gene homologue, negatively regulates shoot cell elongation and lateral root formation, and positively regulates the light response of hypocotyl length
Authors: Nakazawa Miki , Yabe Naoto , Ichikawa Takanari , Yamamoto Yoshiharu Y. , Yoshizumi Takeshi , Hasunuma Kohji , Matsui Minami
Published: August 2010

A novel dominant mutant designated ‘dwarf in light 1’ (dfl1‐D) was isolated from screening around 1200 Arabidopsis activation‐tagged lines. dfl1‐D has a shorter hypocotyl under blue, red and far‐red light, but not in darkness. Inhibition of cell elongation in shoots caused an exaggerated dwarf phenotype in the adult plant. The lateral root growth of dfl1‐D was inhibited without any reduction of primary root length. The genomic DNA adjacent to the right border of T‐DNA was cloned by plasmid rescue. The rescued genomic DNA contained a gene encoding a GH3 homologue. The transcript was highly accumulated in the dfl1‐D. The dfl1‐D phenotype was confirmed by over‐expression of the gene in the wild‐type plant. The dfl1‐D showed resistance to exogenous auxin treatment. Moreover, over‐expression of antisense DFL1 resulted in larger shoots and an increase in the number of lateral roots. These results indicate that the gene product of DFL1 is involved in auxin signal transduction, and inhibits shoot and hypocotyl cell elongation and lateral root cell differentiation in light.
The clinical significance of occult hepatitis B transfusion in Taiwan – a look‐back study
Authors: Su T.‐H. , Chen P.‐J. , Chen T.‐C. , Cheng H.‐R. , Li L. , Lin K.‐S. , Kao J.‐H. , Chen D.‐S. , Liu C.‐J.
Published: August 2010

Objectives: A look‐back study was conducted to determine the clinical significance of occult hepatitis B virus (HBV) blood transfusion in an HBV hyperendemic area.

Aim: To improve the blood transfusion safety.

Background: Occult HBV is transmissible through blood transfusion in HBV‐naÏve recipients. However, its impact on recipients with prevalent HBV infection in HBV hyperendemic areas is unclear.

Methods/Materials: In 2006, 12 occult HBV blood donors were found from 10 824 repository samples by nucleic acid testing. The 74 corresponding recipients were identified and their pre‐ and post‐transfusion clinical information was gathered, and the living recipients were recalled for follow‐up. From the available archival sera, the HBV DNA was examined and sub‐genomic sequences between paired donor and recipient were compared using polymerase chain reaction‐based assays.

Results: Among the 74 recipients, 18 were still alive and 12 returned to our clinic. From the available serological profiles, 76% of recipients had ongoing or recovered HBV infection before transfusion. Only 24 recipients had available post‐transfusion serological profiles and none seroconverted to be hepatitis B surface antigen (HBsAg) positive. Moreover, except for the prior HBsAg carriers, the recipients' HBV DNA levels after transfusion were low (<20 IU/mL). One recipient had identical HBV surface gene sub‐genomic sequence (384 nucleotides) to his donor. After transfusion, no recipient developed post‐transfusion hepatitis (PTH) and the clinical outcome was good.

Conclusion: In HBV hyperendemic areas, occult hepatitis B transfusion might not lead to HBsAg carriage or PTH. The risk of transfusion‐transmitted HBV infection was probably lower than that in non‐endemic areas because most recipients had already experienced HBV infection.
Allergenic cross‐reactivity of yeasts
Authors: Koivikko A. , Kalimo K. , Nieminen E. , Savolainen J. , Viljanen M. , Viander M.
Published: August 2010

Yeast allergen extracts ofCandida albicans, C. pseudotropicalis, C. krusei, C. parapsilosis, C. tropicalis, C. guilliermondi, C. humicola, C. norwegica, C. utilis, Cryptococcus albidus, Geotrichum candidum, Pityrosporon pachydermatis, P. ovale, Rhodotorula minuta, R. rubra, Saccharomyces cerevisiae, Torulopsis glabrataandTrichosporon cutaneumwere investigated regarding their common allergenic properties. The enzyme immunoassay (EIA) using rabbit antiCandida albicansantiserum showed remarkable immunological cross‐reactivity only between theCandidaspecies. However, there was a significant multiple sensitivity to the extracts ofC. albicans, C. utilis, Cr. albidus, R. rubra, andS. cerevisiaein skin prick testing in atopic patients, suggesting the possible presence of one or more common skin reactive allergens.
Efficacy of an oral antihistamine, astemizole, as compared to a nasal steroid spray in hay fever
Authors: Salomonsson P. , Gottberg L. , Heilborn H. , Norrlind K. , Pegelow K.‐O.
Published: August 2010

The efficacy and side effects of the oral H1‐antihistamine, astemizole, were compared with those of nasal beclomethasone in 158 adult birch‐pollen allergic hay fever patients. 148 patients completed the 5‐week, controlled trial which took place in Stockholm, May 1986, during the birch pollen season. Daily pollen counts were found to be at a rather low level throughout the study period. The effect and tolerability of both drugs were found to be excellent, although beclomethasone reduced nasal symptoms (sneezing, rhinorrhoea, blocked nose) significantly more effectively than astemizole. Eye symptoms were mild and equal in both groups. The results indicate that oral astemizole is an effective non‐sedating antihistamine, though less so than nasal beclomethasone, in the treatment of nasal hay fever symptoms.
The Whole Body
Authors: Ownby Dennis R.
Published: August 2010

•Both immunologic and non‐immunologic mechanisms can provoke systemic reactions following food ingestion.

•Histamine is the only mast cell mediator which has been demonstrated to be elevated in the serum as a result of systemic allergic reactions to food.

•In individuals highly sensitive to foods, airborne exposure to food allergens can produce anaphylactic reactions.

•Crossreacting allergens present in some foods and in natural rubber latex can lead to systemic reactions following either latex exposure or food ingestion.
Comparison of roflumilast, an oral anti‐inflammatory, with beclomethasone dipropionate in the treatment of persistent asthma
Authors: Bousquet J. , Aubier M. , Sastre J. , Izquierdo J. L. , Adler L. M. , Hofbauer P. , Rost K.‐D. , Harnest U. , Kroemer B. , Albrecht A. , Bredenbröker D.
Published: August 2010

Background: Roflumilast is an oral, once‐daily phosphodiesterase 4 inhibitor with anti‐inflammatory activity in development for the treatment of asthma. Roflumilast was compared with inhaled beclomethasone dipropionate (BDP) in patients with asthma.

Methods: In a double blind, double‐dummy, randomized, noninferiority study, 499 patients (forced expiratory volume in 1 s [FEV1] = 50–85% predicted) received roflumilast 500 μg once daily or BDP 200 μg twice daily (400 μg/day) for 12 weeks. Lung function and adverse events were monitored.

Results: Roflumilast and BDP significantly improved FEV1by 12% (270 ± 30 ml) and 14% (320 ± 30 ml), respectively (P < 0.0001vsbaseline). Roflumilast and BDP also significantly improved forced vital capacity (FVC) (P < 0.0001vsbaseline). There were no significant differences between roflumilast and BDP with regard to improvement in FEV1and FVC. Roflumilast and BDP showed small improvements in median asthma symptom scores (–0.82 and −1.00, respectively) and reduced rescue medication use (−1.00 and −1.15 median puffs/day, respectively;P < 0.0001vsbaseline). These small differences between roflumilast and BDP were not considered clinically relevant. Both agents were well tolerated.

Conclusions: Once daily, oral roflumilast 500 μg was comparable with inhaled twice‐daily BDP (400 μg/day) in improving pulmonary function and asthma symptoms, and reducing rescue medication use in patients with asthma.
T cell and eosinophil activation in mild and moderate atopic and nonatopic children's asthma in remission
Authors: Pumputiene I. , Emuzyte R. , Dubakiene R. , Firantiene R. , Tamosiunas V.
Published: August 2010

Background:  Inflammation in the pathogenesis of asthma is associated with products of activated T cells and eosinophils. The aim of this study was to determine whether ongoing inflammation persists in children with different phenotypes of asthma despite the disease in remission.

Methods:  Serum samples were collected from 68 children with atopic or nonatopic asthma in remission and from 15 healthy children. Soluble interleukin‐2 receptor (sIL‐2R), IL‐2 and IL‐4 were examined by using an enzyme‐linked immunosorbent assay. Total and specific immunoglobulin E, and eosinophil cationic protein (ECP) were analysed by fluoroimmunoassay (Pharmacia CAP System).

Results:  In patients with moderate persistent atopic asthma, sIL‐2R was increased significantly when compared with mild persistent atopic asthma (P < 0.05). No changes of sIL‐2R were seen in nonatopic asthmatics compared with atopics and controls. The level of IL‐2 was elevated in moderate persistent atopic and nonatopic asthmatic children compared with controls (P < 0.05 and P < 0.05 respectively) and compared with mild persistent atopic asthmatics and mild persistent nonatopic asthmatics (P < 0.05 in both cases). The levels of IL‐4 in most patients and controls remained below the sensitivity of the assay. Eosinophil cationic protein levels in moderate persistent atopic and nonatopic asthmatics were significantly higher than in mild persistent asthma severity cases (P < 0.001 and P < 0.01 respectively) and in healthy children (P < 0.01 in both cases).

Conclusion:  Changes in the concentration of sIL‐2R, IL‐2 and ECP reflect increased T cell and eosinophil activity in relation to the level of severity of asthma in atopic and nonatopic children, thereby proving the presence of persistent inflammation despite the absence of disease symptoms.