bluuebunny/crossref_metadata_2025_split huggingface dataset:
Outcome after renal transplantation in children: Results of follow‐up by nephrologists in a primary referral center
Authors: Adedoyin Olanrewaju , Frank Rachel , Vento Suzanne , Vergara Marcela , Gauthier Bernard , Trachtman Howard 
Published: November 2003

Abstract:  Pediatric patients who receive a kidney transplant require extended follow‐up to monitor graft function and for management of complications. Because of convenience, most patients are sent back to the nephrologists who referred them for transplantation (the primary nephrologist) for long‐term care. As a consequence, many pediatric nephrologists who provide this extended care are not associated with a transplant center. It is not known if this arrangement yields satisfactory outcomes for children and adolescents who receive a kidney transplant.The objective was to determine if clinical outcomes are satisfactory in pediatric renal transplant recipients who were followed up by their primary nephrologists after the procedure. A chart review was carried out on all renal transplant recipients seen in the renal clinic at Schneider Children's Hospital (SCH) from 1982 to 2001. Patients were eligible if they were followed up by the primary referring nephrologists at SCH for a minimum of 6 months after transplantation. Relevant demographic and clinical outcome data were compiled. Twenty‐eight patients who received a total of 33 renal allografts [living related donors (LRD) 15 and cadaveric donors (CD) 18] were seen during the study period. The transplantations in 19 children (68%) were carried out at Montefiore Hospital (Bronx, NY, USA), while the rest were performed at other centers. There were three (11%) deaths, two LRD patients and one CD patient. The group of 25 surviving patients consisted of 17 males and eight females, age range 4–28 yr (mean 17.2 yr). The mean duration of renal allograft survival was 6.3 ± 5.3 yr and the mean duration of follow‐up was 6.1 ± 5.3 yr. The most recent serum creatinine ranged from 0.5 to 3.8 mg/dL with a mean of 1.3 ± 0.8 mg/dL. There were several complications including acute rejection, renal artery stenosis, and hydronephrosis in the allograft. The team of primary referring nephrologists successfully treated all of these except the child with hydronephrosis. The primary nephrologist who refers pediatric patients to a tertiary care transplant center can accomplish long‐term follow‐up of renal transplant recipients after discharge from the transplant center. The clinical outcomes are acceptable and compare favorably with the results described in the literature that have been achieved in patients followed up at transplant centers. Problems rarely developed that required referral back to the transplant center for management. This approach to care is recommended because it is more likely to foster compliance by both patients and parents.
The significance of a defect on DMSA scan in children with renal transplants
Authors: Hutchinson C. , Beckett M. , Kiratli P. , Gordon I , Trompeter R. S. , Rees L. 
Published: November 2003

Abstract:  Since December 1995, pediatric renal transplant recipients in our unit have received a DMSA scan as soon as possible post‐transplant in order to provide a baseline for comparison in the event of subsequent complications.We retrospectively reviewed the case notes and DMSA scans of the 45 patients who underwent a scan within 9 wk of their transplant to see if pre or peri‐transplant factors or post‐transplant complications were associated with defects on scanning. Forty percentage of scans had defects. The presence of defects was not associated with potential predisposing factors such as patient or donor age, cadaveric or live donation, cold ischemia time, multiple donor vessels, the use of non‐heart beating donors, the mean time to scan, the serum creatinine, or the presence of structural renal tract anomalies predisposing to UTI. However, 87% of patients had complications before the scan, including UTI, rejection, acute tubular necrosis, transplant biopsy and drug toxicity.Children with no clinical complications had a significantly reduced risk of a defect (p = 0.035), while biopsy was associated with the presence of defects (p = 0.0034). Twenty patients had one or more follow up DMSA scans: one patient developed a new focal defect. In conclusion, renal transplant defects are frequently found on DMSA scanning even early after transplantation and are non‐specifically associated with many different complications.
Construction and identification of a recombinant live attenuated Salmonella typhimurium vaccine strain carrying Helicobacter pylori heat shock protein subunit B gene
Authors: LI Guo Qing , CHEN Min Hu , JIAO Zhi Yong , ZHU Sen Lin , CHEN Jie , HU Pin Jin 
Published: November 2003

OBJECTIVE:  Because Helicobacter pylori is the principal cause of chronic active gastritis and peptic ulcer disease, the present study explored the possibility of constructing a recombinant live attenuated S. typhimurium vaccine strain carrying H. pylori heat shock protein subunit B (HspB) gene.METHODS:  A 1640‐bp HspB gene was cloned into a prokaryotic expression plasmid pTrc99A. After sequence analysis, the result was compared with the sequence of H. pylori‐HspB gene and protein provided by the Genebank using BLAST analysis. The identified recombinant plasmid was then introduced into a live attenuated S. typhimurium strain SL3261.RESULTS:  Using polymerase chain reaction (PCR) and restriction enzyme digestion, a recombinant pro­karyotic expression plasmid pTrc99A‐HspB harboring the HspB gene was constructed and successfully introduced into a live attenuated S. typhimurium strain SL3261. Most of the H. pylori‐HspB in the recombinant plasmid pTrc99A‐HspB was consistent with the H. pylori‐HspB sequence provided by the Genebank. The exchange of A/T or C/G in the cloned sequence hardly changed the encoded amino acids; the homology for both the genes and proteins of H. pylori SS1 strain was 97%; the homology with other common H. pylori strains J99 and 26695 was 96% for both.CONCLUSION:  A recombinant live attenuated S. typhimurium vaccine strain harboring H. pylori‐HspB gene was successfully constructed and verified, which may help in the development of an oral vaccine against H. pylori infection.
Different T helper type immune responses induced by Helicobacter pylori vaccine in mouse model
Authors: CHEN Jie , CHEN Min Hu , LI Guo Qing , JIAO Zhi Yong , YU Jun , LIANG Wei Qiang , CHEN Wei , HU Pin Jin , SHEN Zu Yao 
Published: November 2003

OBJECTIVE:  To study the protective immune response induced by Helicobacter pylori vaccine in mice.METHODS:  Mice were orally immunized with cholera toxin (CT) plus H. pylori whole‐cell sonicate antigen (group A), CT only (group B) or normal saline (group C), and challenged with H. pylori 4 weeks later. Mice from each group were killed at different time points before and after challenge. Gastric H. pylori colonization, serum anti‐H. pylori IgG1, IgG2a and IgA antibodies, the mRNA expression of both Th1‐type and Th2‐type cytokines in the gastric mucosa and splenic tissue, and mucosal inflammation at different time points were compared among the groups.RESULTS:  Colonization of H. pylori in group A decreased significantly compared with groups B and C at both 5 and 26 weeks after challenge. The serum concentrations of anti H. pylori IgG1, IgG2a and IgA in group A were significantly higher than those of groups B and C at all time points. The mRNA expressions of Th1‐type cytokines in the gastric mucosa of groups A and B were higher than those of group C both before and 5 weeks after H. pylori challenge. At 26 weeks after challenge, Th1‐type cytokines were increased in the gastric mucosa of group C, but decreased in the gastric mucosa of groups A and B, except for IL‐12. Before challenge, Th2‐type cytokines were expressed at a similar level in the gastric mucosa of both group A and group B; 5 weeks after challenge, IL‐4 and IL‐10 expressions were not detectable in either group and the expression of IL‐6 in both groups was lower than that in group C; 26 weeks after challenge, the expression of both IL‐4 and IL‐10 was detected in group A, but only IL‐10 in group B. The expression of IL‐6 was similar in all groups. Both Th1‐ and Th2‐type cytokines were expressed in the splenic tissue of all groups at different time points. Significant gastritis characterized by marked infiltration of mononuclear cells and neutrophils was found in group A at 5 weeks after challenge, but only mild inflammation was present in group B; 26 weeks after challenge, gastritis had increased in group C but decreased in the other two groups.CONCLUSIONS:  The vaccine consisting of H. pylori whole‐cell sonicate antigen and CT induces both Th1 and Th2 immune responses at an early stage. The Th1 response increases early after H. pylori challenge, which contributes to both protective immunity and postimmunization gastritis, whereas the Th2 response increases in the gastric mucosa late after challenge when both the Th1 response and postimmunization gastritis have abated.
Decreased iNOS synthesis mediates dexamethasone‐induced protection of neurons from inflammatory injury in vitro
Authors: Golde Sabine , Coles Alasdair , Lindquist Jonathan A. , Compston Alastair 
Published: November 2003

AbstractBrain inflammation is accompanied by transection of axons and death of neurons in the acute lesions of multiple sclerosis. We explored mechanisms of inflammatory damage to neurons in vitro using cocultures of rat embryonal cortical neurons with microglia activated by interferon‐gamma (IFNγ) and lipopolysaccharide (LPS). Previously, we have demonstrated that microglia are highly toxic to neurons and that nitric oxide (NO) derived from inducible nitric oxide synthase (iNOS) is necessary and sufficient to mediate this toxicity. Here, we show that addition of dexamethasone (1 µM) to activated cocultures provides effective neuroprotection. We demonstrate that dexamethasone down‐regulates NO production of primary microglia by ≈ 50% and reduces steady‐state iNOS protein and mRNA expression by ≈ 70%. These changes were reversed by the glucocorticoid receptor blocker RU‐486. Furthermore, we analysed the stability of iNOS protein and show that whilst inhibitors of the proteasome blocked iNOS degradation they did not reverse the dexamethasone effect. Our results indicate that the main mechanism of corticosteroid activity on iNOS is reduction in protein synthesis, not destabilization as previously suggested.
Effect of NT‐4 and BDNF delivery to damaged sciatic nerves on phenotypic recovery of fast and slow muscles fibres
Authors: Simon Magda , Porter Rebecca , Brown Robert , Coulton Gary R. , Terenghi Giorgio 
Published: November 2003

AbstractWe investigated whether neurotrophin‐4 (NT‐4) and brain‐derived neurotrophic factor (BDNF) affected the reinnervation of slow and fast motor units. Neurotrophin‐impregnated or plain fibronectin (FN) conduits were inserted into a sciatic nerve gap. Fast extensor digitorum longus (EDL) and slow soleus muscles were collected 4 months postsurgery. Muscles were weighed and fibre type proportion and mean fibre diameters were derived from muscle cross‐sections. All fibre types in muscles from FN animals were severely atrophied and this correlated well with type 1 fibre loss and atrophy in soleus and type 2b loss and atrophy in EDL. Treatment with NT‐4 reversed soleus but not EDL mass loss above the FN group by significantly restoring type 1 muscle fibre proportion and diameters towards those of normal unoperated animals. BDNF did not increase muscle mass but did have minor effects on fibre type and diameter. Thus, NT‐4 significantly improved slow motor unit recovery, and provides a basis for therapies intended to aid the functional recovery of muscles after denervating injury.
Restricted daily consumption of a highly palatable food (chocolate Ensure®) alters striatal enkephalin gene expression
Authors: Kelley A. E. , Will M. J. , Steininger T. L. , Zhang M. , Haber S. N. 
Published: November 2003

AbstractBrain opioid peptide systems are known to play an important role in motivation, emotion, attachment behaviour, the response to stress and pain, and the control of food intake. Opioid peptides within the ventral striatum are thought to play a key role in the latter function, regulating the affective response to highly palatable, energy‐dense foods such as those containing fat and sugar. It has been shown previously that stimulation of mu opiate receptors within the ventral striatum increases intake of palatable food. In the present study, we examined enkephalin peptide gene expression within the striatum in rats that had been given restricted daily access to an energy‐dense, palatable liquid food, chocolate Ensure®. Rats maintained on an ad libitum diet of rat chow and water were given 3‐h access to Ensure® daily for two weeks. One day following the end of this period, preproenkephalin gene expression was measured with quantitative in situ hybridization. Compared with control animals, rats that had been exposed to Ensure® had significantly reduced enkephalin gene expression in several striatal regions including the ventral striatum (nucleus accumbens), a finding that was confirmed in a different group with Northern blot analysis. Rats fed this regimen of Ensure® did not differ in weight from controls. In contrast to chronic Ensure®, acute ingestion of Ensure® did not appear to affect enkephalin peptide gene expression. These results suggest that repeated consumption of a highly rewarding, energy‐dense food induces neuroadaptations in cognitive‐motivational circuits.
Developmental elimination of ectopic projection sites for the transgenic OR gene that has lost zone specificity in the olfactory epithelium
Authors: Nakatani Hiroko , Serizawa Shou , Nakajima Miho , Imai Takeshi , Sakano Hitoshi 
Published: November 2003

AbstractIn rodents, olfactory receptor (OR) genes are expressed in one of four zones in the olfactory epithelium (OE), and olfactory sensory neurons (OSNs) expressing the same OR project their axons to a specific set of glomeruli on the olfactory bulb (OB). Using the yeast artificial chromosome (YAC) transgenic system, we have analysed the expression of the murine OR gene MOR29A of the MOR28 cluster located on chromosome 14. Although expression of the endogenous MOR29A was restricted to the most dorsomedial zone, the transgenic MOR29A (Tg MOR29A) was expressed in all four zones of the OE. When the OB of the transgenic mouse was analysed, the axons of the OSNs expressing Tg MOR29A were found to project not only to the dorsal side but also to the ventral side of the OB as well. The ectopic projection sites on the ventral side gradually disappear during postnatal development. Naris occlusion prevents this elimination, suggesting that odorant stimulation is involved in eliminating the ectopic projection sites.
Retrosplenial cortex (BA 29/30) hypometabolism in mild cognitive impairment (prodromal Alzheimer's disease)
Authors: Nestor P. J. , Fryer T. D. , Ikeda M. , Hodges J. R. 
Published: November 2003

AbstractPrevious group studies using positron emission tomography to assess resting cerebral glucose metabolism in very early Alzheimer's disease and mild cognitive impairment have identified the posterior cingulate and adjacent cingulo‐parietal cortex as the first isocortical area to develop hypometabolism. We studied the profile of resting cerebral glucose metabolism in individuals with mild cognitive impairment to assess whether more specific and stereotyped regional hypometabolism would be evident across subjects. The study found that the most consistently hypometabolic region between individual subjects was a subregion of the posterior cingulate, the retrosplenial cortex (BA 29/30). This result is discussed in the context of regional connectivity, focal lesion evidence and functional activation studies of episodic memory paradigms in both normal and Alzheimer's disease groups. We propose that the retrosplenial cortex may represent a key junction between prefrontal areas involved in implementing retrieval strategies for episodic memory and hippocampal‐based mnemonic processing; we therefore interpret the retrosplenial hypometabolism as a probable contributor to the memory impairment seen in mild cognitive impairment by disconnecting these two anatomical networks.
The role of nitric oxide in morphine dependence and withdrawal excitation of rat oxytocin neurons
Authors: Bull Philip M. , Ludwig Mike , Blackburn‐Munro Gordon J. , Delgado‐Cohen Helena , Brown Colin H. , Russell John A. 
Published: November 2003

AbstractMagnocellular oxytocin neurons develop morphine dependence after intracerebroventricular infusion for 5 days as revealed by their profound excitation following naloxone‐induced withdrawal. Oxytocin neurons strongly express nitric oxide synthase (NOS) and nitric oxide (NO) inhibits their activity. This study investigated whether excitation of oxytocin neurons during morphine withdrawal involves reduced activity of NOS and NO. Neuron activity was measured in urethane‐anaesthetized rats with blood sampling for oxytocin radioimmunoassay and extracellular single unit firing rate recording of supraoptic nucleus oxytocin neurons. To compare morphine‐dependent and ‐naive rats oxytocin secretion was measured during stimulation by intravenous hypertonic saline infusion. Prior treatment with Nω‐nitro‐l‐arginine methyl ester, a NOS inhibitor, facilitated osmotically stimulated oxytocin secretion in both morphine‐dependent and ‐naive rats. The facilitation was not different between these groups when corrected for the slower responses observed in morphine‐dependent rats. Treatment of morphine‐dependent rats with Nω‐nitro‐l‐arginine methyl ester also enhanced oxytocin secretion during naloxone‐precipitated withdrawal. Oxytocin neurons excited by withdrawal were recorded during microdialysis application to the supraoptic nucleus of the NO donor sodium nitroprusside alone and in combination with the GABAA antagonist bicuculline. Sodium nitroprusside inhibited oxytocin neurons during naloxone‐precipitated morphine withdrawal and, while bicuculline alone increased firing rate, it did not reduce the inhibition by sodium nitroprusside, in contrast with previous findings in naive rats. Together, these findings indicate that NO restraint of oxytocin secretion is not curtailed during morphine dependence and remains a potent inhibitor of withdrawal excitation despite reduced effectiveness on GABA innervation of the supraoptic nucleus. Hence there is no evidence that changes in NO regulation underlie excitation of oxytocin neurons during opiate withdrawal in morphine dependence.
Neural architecture of choice behaviour in a concurrent interval schedule
Authors: Kalenscher Tobias , Diekamp Bettina , Güntürkün Onur 
Published: November 2003

AbstractConcurrent interval schedules are classic experimental paradigms that are traditionally employed in psychological research on choice behaviour. To analyse the neural basis of choice in a concurrent fixed interval schedule, pigeons were trained to peck on two response keys. Responses were differentially rewarded in key specific short or long time intervals (SI vs. LI). Using tetrodotoxin, we reversibly blocked the neostriatum caudolaterale (NCL, the avian functional equivalent of the prefrontal cortex), avian caudate‐putamen and nucleus accumbens to examine their contribution. A detailed analysis of baseline choice behaviour revealed that response distribution and key affinity were determined by cued or time‐related expectancy for rewards on the SI key. The pigeons' response frequency increased on the SI key and decreased on the LI key with increasing temporal proximity to the SI reward and pigeons switched to the LI key after reward delivery. Pecking bursts on the LI key were negatively correlated with bursts on the SI key. Neostriatum caudolaterale inactivation did not affect pecking activity per se but interfered with reward‐related temporal modulation of pecking frequency, switching pattern and coupling of LI to SI pecks. Blockade of caudate‐putamen resulted in a complete behavioural halt, while inactivation of nucleus accumbens diminished operant behaviour without affecting consummatory responses. These data suggest that the NCL is tuned via indirect striato‐pallial projections to integrate cued or time‐related reward expectancy into a response selection process in order to set, maintain or shift goals. The NCL possibly feeds forward the resulting motor commands to the caudate‐putamen for execution.
Development of an efficient cis‐trans‐cis ribozyme cassette to inactivate plant genes
Authors: Bussière Frédéric , Ledû Sylvain , Girard Marianne , Héroux Maryse , Perreault Jean‐Pierre , Matton Daniel P. 
Published: November 2003

SummaryInactivation of a targeted gene is one of the main strategies used to understand their precise cellular role. In plants, apart from chemical or physical mutagenesis and random insertions of DNA elements followed by screening for a desired phenotype, the most common strategy to inhibit the expression of a given gene involves RNA silencing. This can be achieved either through antisense suppression, sense over‐expression leading to co‐suppression, or expression of double‐stranded DNA constructs (dsRNA). The use of ribozymes to inhibit gene product accumulation has only been occasionally attempted, mainly because of the more complex genetic engineering procedure involved, although the specificity of ribozymes can be an important factor when targeting close members of a gene family. We report here the development of a new cis‐acting ribozyme cassette for the production of RNAs with desired termini. Attention to many details has been brought in order to provide a powerful procedure for plant application. For example, ultrastable GNRA tetraloops were substituted for both loops II and III of cis‐acting hammerhead sequences, thereby favouring folding into the catalytically active structure that results in the self‐cleavage of all transcripts. We demonstrate the usefulness of this cassette by producing a ribozyme that cleaves in trans, originally embedded in the cis‐acting self‐cleaving cassette. The activity of the cis‐trans‐cis construct, was demonstrated both in vitro and in vivo, in transgenic plants with the specific cleavage of an mRNA encoding a 2‐oxo‐glutarate‐dependant dioxygenase predominantly expressed in pistils tissues and in leaves, from the wild potato Solanum chacoense.
Culture and Entrepreneurship – Remarks on Transculturality as Practice
Authors: Pütz Robert 
Published: November 2003

ABSTRACTThe most recent media debate about a new ‘Turkish entrepreneurship’ in Germany triggered off the fundamental reflections on the necessarily critical conceptualisation of the relation between ‘culture’ and entrepreneurial action. The dominating concepts in the field of ‘ethnic business’, in which questions of cultural orientation in entrepreneurial action have been a central issue for some time, can serve as a starting point for this analysis. For understanding the term culture and the conceptualisation of culture in conjunction with entrepreneurial action, a few critical remarks and a shift in perspective are necessary. Contributions of economic geography inspired by the ‘cultural turn’, which shows alternative ways of thinking about the connection between culture and economy by using a new understanding of culture may be utilised here. Focusing on the group of ‘German‐Turkish entrepreneurs’ and bearing in mind the idea of ‘transculturality in practice’ this paper will conclude with an outline of a number of conceptual considerations for action‐oriented research on the relation between culture and entrepreneurial action.