bluuebunny/crossref_metadata_2025_split huggingface dataset:
Hsp20, a novel α‐crystallin, prevents Aβ fibril formation and toxicity
Authors: Lee Sungmun , Carson Kenneth , Rice‐Ficht Allison , Good Theresa 
Published: February 2005

Abstractβ‐Amyloid (Aβ) is a major protein component of senile plaques in Alzheimer's disease, and is neurotoxic when aggregated. The size of aggregated Aβ responsible for the observed neurotoxicity and the mechanism of aggregation are still under investigation; however, prevention of Aβ aggregation still holds promise as a means to reduce Aβ neurotoxicity. In research presented here, we show that Hsp20, a novel α‐crystallin isolated from the bovine erythrocyte parasite Babesia bovis, was able to prevent aggregation of denatured alcohol dehydrogenase when the two proteins are present at near equimolar levels. We then examined the ability of Hsp20 produced as two different fusion proteins to prevent Aβ amyloid formation as indicated by Congo Red binding; we found that not only was Hsp20 able to dramatically reduce Congo Red binding, but it was able to do so at molar ratios of Hsp20 to Aβ of 1 to 1000. Electron microscopy confirmed that Hsp20 does prevent Aβ fibril formation. Hsp20 was also able to significantly reduce Aβ toxicity to both SH‐SY5Y and PC12 neuronal cells at similar molar ratios. At high concentrations of Hsp20, the protein no longer displays its aggregation inhibition and toxicity attenuation properties. Size exclusion chromatography indicated that Hsp20 was active at low concentrations in which dimer was present. Loss of activity at high concentrations was associated with the presence of higher oligomers of Hsp20. This work could contribute to the development of a novel aggregation inhibitor for prevention of Aβ toxicity.
Mucosal expression of cyclooxygenase isoforms 1 and 2 is increased with worsening damage to the gastric mucosa
Authors: Bhandari P , Bateman A C , Mehta R L , Patel P 
Published: February 2005

Aims : To test the hypothesis that both COX‐1 and COX‐2 expression in human gastric mucosa is up‐regulated in the presence of inflammation as seen in patients with gastritis and gastric ulcers.Methods and results : We performed immunohistochemistry using COX‐1 and COX‐2 monoclonal antibodies on gastric biopsies from 59 patients with normal mucosa, gastritis and gastric ulcers. Expression of COX‐1 and COX‐2 was quantified using an intensity proportion scoring system. Expression of COX‐1 was primarily seen in the lamina propria mononuclear cells with some expression in deep gastric glands in the ulcer group. Expression of COX‐2 was primarily seen in the deep gastric glands with focal expression in the lamina propria mononuclear cells. We found a stepwise increase in the expression of both COX‐1 and COX‐2 as mucosal damage progressed from normal to gastritis to gastric ulcer.Conclusions : We conclude that both COX‐1 and COX‐2 expression in the gastric mucosa are increased in the setting of gastritis and gastric ulceration. Although this increased expression may be due, at least in part, to an increase in inflammatory cell numbers, this study raises the possibility that both COX‐1 and COX‐2 are inducible, contrary to the traditionally held view of only COX‐2 being inducible.
Protein–DNA interactions in the T4 dNTP synthetase complex dependent on gene 32 single‐stranded DNA‐binding protein
Authors: Kim JuHyun , Wheeler Linda J. , Shen Rongkun , Mathews Christopher K. 
Published: February 2005

SummaryOur laboratory has reported data suggesting a role for T4 phage gene 32 single‐stranded DNA‐binding protein in organizing a complex of deoxyribonucleotide‐synthesizing enzymes at the replication fork. In this article we examined the effects of gene 32 ablation on the association of these enzymes with DNA–protein complexes. These experiments showed several deoxyribonucleotide‐synthesizing enzymes to be present in DNA–protein complexes, with some of these associations being dependent on gene 32 protein. To further understand the role of gp32, we created amber mutations at codons 24 and 204 of gene 32, which encodes a 301‐residue protein. We used the newly created mutants along with several experimental approaches – DNA‐cellulose chromatography, immunoprecipitation, optical biosensor analysis and glutathione‐S‐transferase pulldowns – to identify relevant protein–protein and protein–DNA interactions. These experiments identified several proteins whose interactions with DNA depend on the presence of intact gp32, notably thymidylate synthase, dihydrofolate (DHF) reductase, ribonucleotide reductase (RNR) and Escherichia coli nucleoside diphosphate (NDP) kinase, and they also demonstrated direct associations between gp32 and RNR and NDP kinase, but not dCMP hydroxymethylase, deoxyribonucleoside monophosphate kinase, or DHF reductase. Taken together, the results support the hypothesis that the gene 32 protein helps to recruit enzymes of deoxyribonucleoside triphosphates synthesis to DNA replication sites.
In vivo analysis of the roles of conserved aspartate and histidine residues within a complex response regulator
Authors: Li Lina , Kehoe David M. 
Published: February 2005

SummaryRcaC is the founding member of a group of large response regulators with complex domain combinations containing at least two receiver domains, an OmpR‐class winged helix‐turn‐helix DNA binding domain, and a histidine phosphotransfer (HPt) domain. Within its two receiver and HPt domains, RcaC contains consensus phosphorylation sites at aspartates 51, 576 and histidine 316. RcaC operates in the pathway regulating transcription of genes encoding components of photosynthetic light harvesting antenna to changes in light colour. We show that phycocyanin gene expression requires RcaC. RcaC contributes to light regulation of phycoerythrin genes, but is not part of the second light regulation pathway controlling these genes. Substitutions at aspartate 51 or histidine 316 severely impaired light responsiveness while substitutions at aspartate 576 had little effect. Complete loss of light regulation, measured by phycocyanin gene expression, only occurred in the triple mutant. We conclude that aspartate 51 primarily controls light colour responsiveness and is regulated by histidine 316, and that these residues are likely phosphorylated in red light and dephosphorylated in green light. The carboxy‐terminal receiver domain has a minor role in controlling this response. RcaC abundance is also light regulated and depends on aspartate 51 and histidine 316, but not aspartate 576.
Coupling isoprene and monoterpene emissions from Amazonian tree species with physiological and environmental parameters using a neural network approach
Authors: SIMON E. , KUHN U. , ROTTENBERGER S. , MEIXNER F. X. , KESSELMEIER J. 
Published: February 2005

ABSTRACTThe ability to predict isoprene emissions from plants is important for predicting atmospheric chemistry. To improve the basis for prediction capability, data obtained from continuous field measurements of isoprene and monoterpene emissions from three Amazonian tree species were related to observed environmental and leaf physiological parameters using a new neural network approach. The environmental parameters included leaf temperature, light, relative humidity, water vapour pressure deficit, and the history of ambient temperature and ozone concentration, whereas the physiological parameters included stomatal conductance, assimilation and intercellular CO2concentration. The neural approach with 24 different combinations of these parameters was applied to predict the emission variability observed during short time periods (2–3 d) with individual tree branches and, on a longer‐term scale, in aggregated data sets from different seasons, leaf developmental stage, and light environment. The results were compared to the quasi standard emission algorithm for isoprene. On the short‐term scale, good agreement (r2≈ 0.9) was obtained between observations and predictions of the standard algorithm as well as predictions of the neural network using the same input parameters (leaf temperature and light). When these predictors were used to model the long‐term emission variability,r2was reduced to < 0.5 for both approaches. Remarkably, for the neural technique, more than 50% of the unexplained variance could be explained by the mean temperature of the preceding 36 h. An even better network performance was obtained with physiological parameter combinations (r2 > 0.9) suggesting a strong and applicable link between isoprenoid emission and leaf primary metabolism.
Hepatitis B virus genotypes and precore mutations in Scottish blood donors
Authors: Davidson F. , Lycett C. , Sablon E. , Petrik J. , Dow B. C. 
Published: February 2005

Background and Objectives  This study was carried out to determine the frequency of hepatitis B virus (HBV) core promoter variants (nucleotide positions 1762, 1764) and precore variants (nucleotide position 1896) in hepatitis B surface antigen (HBsAg)‐positive Scottish blood donors. HBV genotypes present in this population were also indentified.Materials and Methods  A total of 85 HBsAg‐positive blood donor samples were included in the study. Of these, 79 were polymerase chain reaction (PCR) positive and had sequence and mutation information. They were divided into two groups: group 1 (23 individuals) were hepatitis B e antigen (HBeAg)‐positive and negative for antibody to HBe (anti‐HBe); and group 2 (56 individuals) were HBeAg negative and positive for anti‐HBe. A line probe assay was used to detect mutations, and a comparison was made by using direct sequence analysis. A different line probe assay was used to identify HBV genotype.Results  The frequencies of mutations in group 1 were 22% each for mutations 1762, 1764 and 1896, increasing to 26%, 35% and 55% in group 2, respectively. By contrast, direct sequence analysis failed to identify 70% of wild‐type/mutant mixes. The prevalence of viral genotypes was 41% for genotype A, 12% for genotype B, 5% for genotype C, 30% for genotype D and 12% for mixed‐genotype infections. Precore mutations were seen in 10%, 88%, 25% and 74% of genotypes A, B, C and D, respectively.Conclusions  The results indicate that core promoter and/or precore mutants may be under‐reported. The combination of HBV PCR and line probe assays is useful for supplementing HBV serological tests. Non‐Caucasian genotypes are present in the UK blood‐donating population and will therefore affect the demographics of HBV infection.
Infliximab in the surgical management of complex fistulating anal Crohn's disease
Authors: Talbot C. , Sagar P. M. , Johnston M. J. , Finan P. J. , Burke D. 
Published: February 2005

AbstractObjectives  To assess prospectively the efficacy and safety of treatment of perianal Crohn's disease by means of a combination of surgical management and a standardized protocol for the intravenous infusion of infliximab.Methods  A consecutive series of patients who presented with complex perianal Crohn's fistulae between November 1999 and March 2003 were included in the study. Perianal sepsis was eradicated with drainage of collections and insertion of setons. Infliximab was infused at 5 mg/kg at 0, 2, and 6 weeks. Setons were removed after the second infliximab infusion. Endpoints were defined as either complete, partial or no response as noted at subsequent outpatient follow up. Adverse reactions were recorded.Results  Twenty‐one patients had a median of three fistulae per patient (range 1–9). All patients tolerated the initial protocol, receiving a median of five infusions of infliximab (range 3–19); median follow up 20 months (range 12–52). Eleven patients (53%) were continued on maintenance therapy with 12 weekly infusions of infliximab for either a perceived clinical need for treatment or after a relapse of their symptoms. Ten (47%) patients experienced a complete response to treatment and the remaining 11 (53%) experienced a partial response. No patient failed to respond to treatment. Four adverse reactions were noted (2 mild allergies, 1 rash and 1 patient experienced joint pains). All adverse reactions settled with cessation of the drug infusion.Conclusions  The combination of seton drainage and infusion of infliximab completely healed the perineum of 47% patients with complex fistulating perianal Crohn's disease. Partial response was seen in the remainder of patients. No serious adverse reactions reported.
The role of rectocele repair in targeted patients with obstructed defaecation
Authors: Hirst G. R. , Hughes R. J. , Morgan A. R. , Carr N. D. , Patel B. , Beynon J. 
Published: February 2005

AbstractIntroduction  Obstructed defaecation is a complex disorder that poses serious management challenges. The purpose of this study is to review the functional results of surgery in women undergoing rectocele repair for obstructed defaecation, and in a targeted subgroup in which the rectocele was the only identifiable cause of their symptoms.Methods  All case notes were reviewed. Demographic details, preoperative symptoms, details of previous pelvic surgery, radiological and anorectal physiology results, operative procedure, post operative symptoms, length of follow‐up and details of further pelvic reconstructive surgery were recorded. To enter the targeted group, patients (i) had not undergone previous pelvic surgery, (ii) had presented with obstructive defaecation, (iii) had a proctogram that demonstrated a rectocele with no or partial intrarectal intussusception and (iv) had no other functional abnormality in colonic transit studies, endoanal ultrasound or anorectal physiology.Results  Eighty‐two case notes were reviewed. All experienced obstructed defaecation. Forty‐two women underwent a per‐anal plication of the rectocele, 33 had a transperineal plication and levatorplasty and seven a mesh repair. A total of 63 (77%) women were pleased with the result, though symptoms later returned in 17 (27%) of them. 26 (31%) had further surgery in an attempt to improve their defaecatory difficulties. Sixteen women were eligible for the targeted group. All had a good early result though symptoms returned in three women. Two (12%) had further surgery.Conclusion  Careful preoperative patient selection is vital to improve outcomes. Preoperative counselling of all patients undergoing rectocele repair is of extreme importance, in particular explaining the evolving nature of pelvic floor dysfunction and the possible need for further reconstructive surgery.
Laparoscopic specimen extraction: morcellation
Authors: Varkarakis Ioannis , Rha Khoon , Hernandez Fernando , Kavoussi Louis R. , Jarrett Thomas W. 
Published: February 2005

OBJECTIVESTo review our experience with intact extraction and morcellation of nephrectomy specimens, and the advantages and disadvantages of morcellation indicated by current reports.PATIENTS AND METHODSIn a previous study, 56 consecutive patients undergoing radical and simple transperitoneal laparoscopic nephrectomy were prospectively evaluated. Morcellation specimens (33) were extracted at the umbilical or lateral port sites and intact specimens (23) through an infra‐umbilical incision. Data were obtained on pathology, narcotic requirements, hospital stay, complications, estimated blood loss, size of renal mass based on preoperative imaging, specimen weight and extraction incision lengthRESULTSThe mean incision length was 1.2 cm in the morcellation group and 7.1 cm in the intact group (P < 0.001). There were no significant differences in pain or recovery between the groups. In two cases of tumour nephrectomy, microscopic invasion of the perinephric adipose tissue in the intact specimen group were up‐staged from clinical T1 to pT3a disease; there was no change in patient treatment based on this information.CONCLUSIONSWith proper technique, morcellation is safe for extracting renal tumours. The specimen can be evaluated for histology but not for pathological staging, limiting its use with transitional cell carcinoma. Port‐site seeding is rare, and does not appear to be more frequent than with open nephrectomy. Although morcellation is cosmetically more desirable, there was no significant advantage in operating time, pain or duration of hospital stay. The choice of extraction method depends on the surgeon's preference and patient choice.
Broadening experience with the retrograde endoscopic management of upper urinary tract urothelial malignancies
Authors: Johnson G.B. , Fraiman M. , Grasso M. 
Published: February 2005

OBJECTIVETo evaluate the results of the retrograde endoscopic treatment of upper urinary tract urothelial malignancies (UUTUM) in an attempt to preserve renal function while also obtaining an acceptable oncological result.PATIENTS AND METHODSSince 1995, 63 patients who were referred for retrograde endoscopic management of UUTUM were evaluated and treated. All patients had an initial diagnostic ureteroscopy and biopsy to obtain histopathological grading. Additional imaging studies were obtained to exclude metastatic disease. The treatment was directed by tumour grade at presentation and medical comorbidity. Tumour volume and multifocality did not exclude patients from vigorous endoscopic treatment. Tumours were resected with electrocautery, holmium‐YAG and Nd:YAG laser. Follow‐up endoscopic surveillance was initially at 3‐month intervals, with increasing intervals in patients with repeatedly negative findings.RESULTSThe tumour grade at presentation was high in 14 (22%), moderate in six (10%), low in 35 (55%) and carcinoma in situ in eight (13%), with 13 (20%) presenting with or subsequently developing bilateral disease. Twenty patients had a nephroureterectomy as they were not amenable to endoscopic treatment. Medical comorbidities necessitated palliative endoscopic therapy of high‐grade tumour in six patients; the remaining 35 had low‐grade tumour and were managed with retrograde endoscopic therapy. Recurrent low‐grade disease was identified in 24 with a mean (range) time to recurrence of 15 (3–63) months. There was concurrent low‐grade bladder cancer in 21 (60%) of the patients. The mean (range) follow‐up was 32 (3–84) months. No patient with low‐grade tumour progressed in grade or stage, and all but one who presented with high‐grade tumour progressed.CONCLUSIONThe retrograde endoscopic management of UTTUMs is particularly useful for patients who present with low‐grade lesions, providing good oncological control and preserving renal function. These patients require a careful and consistent follow‐up, as many will develop recurrent disease. Treatment of higher‐grade lesions is at best palliative.
Agrobacterium‐mediated RMCE approach for gene replacement
Authors: Nanto Kazuya , Yamada‐Watanabe Keiko , Ebinuma Hiroyasu 
Published: February 2005

SummaryWe describe the site‐directed integration (SDI) system for Agrobacterium‐mediated transformation to precisely integrate a single copy of a desired gene into a predefined target locus by recombinase‐mediated cassette exchange (RMCE). The system requires the selection of a transformed line with an integrated copy of a target cassette, and subsequent introduction of an exchange vector. The target cassette contains the npt and cod genes between oppositely orientated recognition sites (RS). The exchange vector T‐DNA possesses an exchange cassette containing the gene of interest and a selectable marker gene, such as hpt, between oppositely orientated (inner) RS. Adjacent to the exchange cassette are ipt and recombinase (R) genes and an additional (outer) RS. The recombinase catalyses double‐crossover between target RS and exchange inner RS to replace the integrated target cassette with the introduced exchange cassette. Transgenic plants that contain randomly integrated copies of the exchange vector T‐DNA show an abnormal phenotype as a result of the overproduction of cytokinin from ipt gene expression. The recombinase can also act on the directly orientated outer RS to remove such randomly integrated copies. The system resulted in single‐copy exchange into the target site only in regenerated tobacco at a frequency of 1%−3% per treated explant, or 4%−9% per regenerated line of normal phenotype. Thus, transgenic plants with only an exchanged copy can be efficiently accumulated and selected. Here, we show that the SDI system can efficiently replace the target cassettes with the exchange cassettes in a heterozygous or homozygous condition. The SDI system may be useful for precise comparisons of different gene constructs, the characterization of different chromosomal regions and the cost‐effective screening of reliable transgenic plants.
ERP correlates of involuntary attention capture by prosodic salience in speech
Authors: Wang Jingtian , Friedman David , Ritter Walter , Bersick Michael 
Published: February 2005

AbstractThis study addressed whether temporally salient (e.g., word onset) or prosodically salient (e.g., stressed syllables) information serves as a cue to capture attention in speech sound analysis. In an auditory oddball paradigm, 16 native English speakers were asked to ignore binaurally presented disyllabic speech sounds and watch a silent movie while ERPs were recorded. Four types of phonetic deviants were employed: a deviant syllable that was either stressed or unstressed and that occurred in either the first or second temporal position. The nature of the phonetic change (a change from a voiced consonant to its corresponding unvoiced consonant) was kept constant. MMNs were observed for all deviants. In contrast, the P3a was only seen when the deviance occurred on stressed syllables. The sensitivity of the P3a to the stress manipulation suggests that prosodic rather than temporal salience captures attention in unattended speech sounds.
A comparison of psychophysiological and self‐report measures of BAS and BIS activation
Authors: Brenner Sharon L. , Beauchaine Theodore P. , Sylvers Patrick D. 
Published: February 2005

AbstractThe behavioral approach (BAS) and behavioral inhibition (BIS) systems are central to theories of both personality and psychopathology, yet agreement on methods of assessing BAS and BIS sensitivity has yet to emerge. We compare the Carver and White (1994) BIS/BAS scales with putative physiological markers of BAS (pre‐ejection period [PEP], respiratory sinus arrhythmia [RSA]) and BIS (electrodermal responding) reactivity during reward and extinction among 50 undergraduates. PEP, RSA, and electrodermal activity each responded strongly to one or more task conditions, but correlations with BIS/BAS scores were stronger for measures of affectivity than for any physiological marker. Finally, PEP reactivity was the only autonomic index that responded only to reward. These findings suggest that (a) self‐report and physiological measures of BAS and BIS reactivity are independent, and (b) PEP may be superior to RSA as an index of approach motivation.
Polymorphic CA/GT and GA/CT microsatellite loci forOstrinia nubilalis(Lepidoptera: Crambidae)
Authors: COATES BRAD S. , HELLMICH RICHARD L. , LEWIS LESLIE C. 
Published: February 2005

AbstractTen polymorphic dinucleotide (CA/GT and GA/CT) microsatellite loci suitable for population genetic screening were characterized from enriched partialOstrinia nubilalisgenomic libraries. Sequence from 126 enriched small insert genomic library clones identified 25 CA/GT and 58 GA/CT loci that were unique. Perfect repeats tended to be short (n = 10–12). Ten microsatellites, PCR amplified from a Crawfordsville Iowa population showed a mean of 10 alleles per locus (range six to 20), and six of 10 loci showed heterozygote deficiency. Amplification of eight loci was observed in the sister speciesO.furnicalis.