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J Arnold

Publications and source records attributed to J Arnold.

At least 37 records · Page 2Linked to original sources
PubMed2001

Sequence analysis and population data on the 'new' short tandem repeat locus D5S2360.

We have studied the sequence structure and population genetics of a 'new' short tandem repeat polymorphism at locus D5S2360 in German Caucasians. Sequencing at this locus revealed a considerable variation, which is characterized by a tetranucleotide (AGAT)(n) repeat pattern with (GAT), (AGATT), and (AG) repeats dispersed throughout the alleles. These microvariations do not necessarily alter the size of the alleles. They may vary by one or two pairs or they may remain unchanged in size. At locus D5S2360 we observed 33 allelic lengths comprising at least 36 different alleles. Population data revealed a high polymorphism with a heterozygosity rate of approximately 92.5%.

Alleles↗
PubMed2001

Enhanced bioavailability of calcitonin formulated with alkylglycosides following nasal and ocular administration in rats.

PURPOSE: The purpose of this study was to characterize the effects of alkylglycosides on the bioavailability of calcitonin following nasal and ocular administration. METHODS: A salmon calcitonin specific radioimmunoassay kit was used to measure calcitonin levels in anesthetized rats at various times after nasal or ocular administration of calcitonin formulated with saline or with octylmaltoside, a medium chain length alkylglycoside or tetradecylmaltoside, a long chain alkylglycoside. The extent of calcitonin absorption was determined directly from the plasma calcitonin level-time curve and the bioavailability of calcitonin was determined from the area under the plasma calcium level-time curve. The calcium level was determined using a colorimetric method. RESULTS: When the nasal formulation contained calcitonin plus saline or 0.125% octylmaltoside, little or no calcitonin was absorbed. However, plasma calcitonin levels were increased and plasma calcium levels were decreased when the nasal formulation contained calcitonin plus 0.125% or 0.25% tetradecylmaltoside. Maximal calcitonin levels were observed 7.5-10 min after nasal administration of the formulation. Ocular administration of calcitonin formulated with tetradecylmaltoside also resulted in calcitonin absorption, but less calcitonin absorption was found after ocular administration than after nasal administration. CONCLUSION: The experimental data indicate that tetradecylmaltoside, but not octylmaltoside. can be effectively used to enhance the bioavailability of nasally and ocularly administered calcitonin.

Absorption↗
PubMed2001

Anti-beta 2 glycoprotein 1 and anti-annexin V antibodies in women with recurrent miscarriage.

While it has been established that anti-phospholipid antibodies (aPL) are associated with recurrent miscarriage (RM), the importance of anti-beta2 glycoprotein 1 (GP1) IgG and anti-annexin V IgG antibodies as risk factors for RM is undefined. We have investigated the prevalence of anti-beta2 GP1 IgG and anti-annexin V IgG antibodies in 54 aPL-positive and 48 aPL-negative women with RM. The prevalence of IgG anti-beta2 GP1 antibodies was not significantly different in persistently aPL-positive women with RM (7%), aPL-negative women with RM (6%) and the normal parous control group (3%). Anti-annexin V IgG antibody prevalence was significantly increased in aPL-positive women with RM compared with aPL-negative women with RM (P = 0.01). The elevations were found in 35%, 19% and 16% of aPL-positive women with RM, aPL-negative women with RM and the control group respectively. No women showed positivity for both anti-beta2 GP1 IgG and anti-annexin V antibodies. Anti-beta2 GP1 IgG antibodies do not appear to be contributory to the investigation of women with RM. Anti-annexin V antibody positivity, although associated with aPL positivity in women with RM, is not an independent risk marker.

Abortion, Habitual↗
PubMed2001

Psychologic morbidity and health-related quality of life of patients assessed in a chest pain observation unit.

STUDY OBJECTIVES: We sought to measure psychologic morbidity and health-related quality of life among patients attending the hospital with acute chest pain both at presentation and 1 month after rigorous assessment for cardiac disease. METHODS: Consecutive patients undergoing assessment on the chest pain observation unit of a large, urban emergency department were asked to complete 3 questionnaires: the Short Form-36 Health Survey (SF-36), the Euroqol Health Utility Questionnaire, and the Hospital Anxiety and Depression Scale. The same questionnaires were mailed 1 month later, along with a questionnaire documenting subsequent pain and reassurance. RESULTS: At enrollment (n=166), 32 (19%) participants (95% confidence interval [CI] 15% to 26%) were experiencing moderate levels of anxiety, and 21 (13%, 95% CI 8% to 19%) were experiencing moderate levels of depression. Health utility and all SF-36 dimensions of quality of life were substantially below age-adjusted normal values. One month after assessment (n=110), only the Pain dimension score of SF-36 had significantly improved. Most scores were unchanged, and the Physical Role and Mental Health dimension scores of SF-36 had significantly deteriorated. Seventy (64%) patients (95% CI 54% to 72%) had further pain after discharge. Despite these findings, 98 (86%) patients (95% CI 78% to 91%) responded that their assessment was "completely reassuring" or "quite reassuring." CONCLUSION: Patients with acute, undifferentiated chest pain have substantial psychologic morbidity and impairment of quality of life. Although patients respond that they are reassured by chest pain observation unit assessment, anxiety and depression remain prevalent and quality of life remains impaired 1 month after assessment.

Acute Disease↗
PubMed2001

Breaking away from grounded identity? Women academics on the Web.

The World Wide Web has provided a new way for academics to find out about others' work and to present versions of their identity. In previous discussions we analyzed how people present themselves in this new medium, in terms of Goffman's ideas of the presentation of self, and commented on gender differences and how issues of credibility and authority are handled by women academics in their homepages. This paper reports discussions with women academics about how they have responded to this opportunity, both in how they present themselves in their own pages, and how they deal with the problems involved in presenting an individual identity within an institutional Web page framework. In presenting themselves in personal homepages, many women academics feel a need to establish their credentials and entitlement to an academic identity. However, the vulnerability of themselves as women remains part of their persona as academics. For example, they were ambivalent about the use of a self-photo on their homepages (most wanted to avoid it, but found it friendly and validating on other women's pages). The discussion considers how far new technology provides opportunities for new forms of identity, or how far the identity presented on the Web is still grounded in people's physical and institutional existence. Women academics feel that the Web has given them new freedom and reduces some traditional gender and status differences (as has been found with other aspects of electronic communication), but they are still wary of it being "yet another way of carrying on the same old gender plot."

Communication↗
PubMed2001

An analysis of gene-finding programs for Neurospora crassa.

MOTIVATION: Computational gene identification plays an important role in genome projects. The approaches used in gene identification programs are often tuned to one particular organism, and accuracy for one organism or class of organism does not necessarily translate to accurate predictions for other organisms. In this paper we evaluate five computer programs on their ability to locate coding regions and to predict gene structure in Neurospora crassa. One of these programs (FFG) was designed specifically for gene-finding in N.crassa, but the model parameters have not yet been fully 'tuned', and the program should thus be viewed as an initial prototype. The other four programs were neither designed nor tuned for N.crassa. RESULTS: We describe the data sets on which the experiments were performed, the approaches employed by the five algorithms: GenScan, HMMGene, GeneMark, Pombe and FFG, the methodology of our evaluation, and the results of the experiments. Our results show that, while none of the programs consistently performs well, overall the GenScan program has the best performance on sensitivity and Missing Exons (ME) while the HMMGene and FFG programs have good performance in locating the exons roughly. Additional work motivated by this study includes the creation of a tool for the automated evaluation of gene-finding programs, the collection of larger and more reliable data sets for N.crassa, parameterization of the model used in FFG to produce a more accurate gene-finding program for this species, and a more in-depth evaluation of the reasons that existing programs generally fail for N.crassa. AVAILABILITY: Data sets, the FFG program source code, and links to the other programs analyzed are available at http://jerry.cs.uga.edu/~wang/genefind.html. CONTACT: eileen@cs.uga.edu.

Algorithms↗
PubMed2001

Physical mapping with automatic capture of hybridization data.

MOTIVATION: Contig maps are a type of physical map that show the native order of a set of overlapping genomic clones. Overlaps between clones can be detected by finding common sequences using a number of experimental protocols including hybridization of probes. All current mapping algorithms of which we are aware require that hybridizations be scored using a fixed number of discrete values (typically 0/1 or high/medium/low). When hybridization data is captured automatically using digital equipment, this provides the opportunity for hybridization intensities to be used in map construction. More fine-grained distinctions in the levels of hybridization may be exploited by algorithms to generate more accurate physical maps. RESULTS: We describe an approach to creating contig maps that uses measured hybridization intensities instead of data scored with a fixed number of discrete values. We describe and compare four algorithms for creating physical maps with hybridization intensities. Simulations using measured intensities sampled from actual data on Aspergillus nidulans indicate that using hybridization intensities rather than data that is automatically scored with respect to threshold values may yield more accurate physical maps.

Algorithms↗
PubMed2001

The Neurospora crassa genome: cosmid libraries sorted by chromosome.

A Neurospora crassa cosmid library of 12,000 clones (at least nine genome equivalents) has been created using an improved cosmid vector pLorist6Xh, which contains a bacteriophage lambda origin of replication for low-copy-number replication in bacteria and the hygromycin phosphotransferase marker for direct selection in fungi. The electrophoretic karyotype of the seven chromosomes comprising the 42.9-Mb N. crassa genome was resolved using two translocation strains. Using gel-purified chromosomal DNAs as probes against the new cosmid library and the commonly used medium-copy-number pMOcosX N. crassa cosmid library in two independent screenings, the cosmids were assigned to chromosomes. Assignments of cosmids to linkage groups on the basis of the genetic map vs. the electrophoretic karyotype are 93 +/- 3% concordant. The size of each chromosome-specific subcollection of cosmids was found to be linearly proportional to the size of the particular chromosome. Sequencing of an entire cosmid containing the qa gene cluster indicated a gene density of 1 gene per 4 kbp; by extrapolation, 11,000 genes would be expected to be present in the N. crassa genome. By hybridizing 79 nonoverlapping cosmids with an average insert size of 34 kbp against cDNA arrays, the density of previously characterized expressed sequence tags (ESTs) was found to be slightly <1 per cosmid (i.e., 1 per 40 kbp), and most cosmids, on average, contained an identified N. crassa gene sequence as a starting point for gene identification.

Bacteriophage lambda↗
PubMed2001

Characterization of agglutinin-like sequence genes from non-albicans Candida and phylogenetic analysis of the ALS family.

The ALS (agglutinin-like sequence) gene family of Candida albicans encodes cell-surface glycoproteins implicated in adhesion of the organism to host surfaces. Southern blot analysis with ALS-specific probes suggested the presence of ALS gene families in C. dubliniensis and C. tropicalis; three partial ALS genes were isolated from each organism. Northern blot analysis demonstrated that mechanisms governing expression of ALS genes in C. albicans and C. dubliniensis are different. Western blots with an anti-Als serum showed that cross-reactive proteins are linked by beta 1,6-glucan in the cell wall of each non-albicans Candida, suggesting similar cell wall architecture and conserved processing of Als proteins in these organisms. Although an ALS family is present in each organism, phylogenetic analysis of the C. albicans, C. dubliniensis, and C. tropicalis ALS genes indicated that, within each species, sequence diversification is extensive and unique ALS sequences have arisen. Phylogenetic analysis of the ALS and SAP (secreted aspartyl proteinase) families show that the ALS family is younger than the SAP family. ALS genes in C. albicans, C. dubliniensis, and C. tropicalis tend to be located on chromosomes that also encode genes from the SAP family, yet the two families have unexpectedly different evolutionary histories. Homologous recombination between the tandem repeat sequences present in ALS genes could explain the different histories for co-localized genes in a predominantly clonal organism like C. albicans.

Agglutinins↗
PubMed2001

Genome of the bacterium Streptococcus pneumoniae strain R6.

Streptococcus pneumoniae is among the most significant causes of bacterial disease in humans. Here we report the 2,038,615-bp genomic sequence of the gram-positive bacterium S. pneumoniae R6. Because the R6 strain is avirulent and, more importantly, because it is readily transformed with DNA from homologous species and many heterologous species, it is the principal platform for investigation of the biology of this important pathogen. It is also used as a primary vehicle for genomics-based development of antibiotics for gram-positive bacteria. In our analysis of the genome, we identified a large number of new uncharacterized genes predicted to encode proteins that either reside on the surface of the cell or are secreted. Among those proteins there may be new targets for vaccine and antibiotic development.

Bacterial Proteins↗
PubMed2001

Is a chest pain observation unit likely to be cost saving in a British hospital?

BACKGROUND: Studies from the United States (US) suggest that using a chest pain observation unit (CPOU) saves from $567 to $2,030 per case compared with hospital admission. These savings will only be reproduced in the United Kingdom (UK) if the cost of routine hospital admission is similar. This study aimed to review current practice to determine the proportion of patients suitable for CPOU evaluation, the cost per case of routine admission and compare this with control groups in US studies. METHODS: 300 patients were randomly selected from those admitted with chest pain between January and June 1998. Two independent observers reviewed the case notes to determine who would have been suitable for CPOU management. Resource use of those selected was then determined. RESULTS: Notes were retrieved for 285 patients. A total of 106 (37.2%) were suitable for CPOU care. Mean length of stay was 51 hours (median 24). Only two patients were admitted to the coronary care unit. Interventional cardiology was limited to two angiograms, one angioplasty and one bypass graft. Estimated mean cost per patient was 458 pounds ($733) with interventional cardiology included, 356 pounds ($570) without. CONCLUSION: Potential exists for the introduction of CPOU care to reduce health service costs in the UK. However, the magnitude of cost savings demonstrated in US studies were achieved by comparison to relatively high inpatient costs and should not be extrapolated. Economic evaluation of the CPOU should be repeated in the UK. The inclusion of interventional cardiology costs is an important determinant of cost effectiveness.

Adult↗
PubMed2000

Sequence variants of DLC1 in colorectal and ovarian tumours.

Loss of heterozygosity occurs frequently on the short arm of chromosome 8 in many neoplasms, including colorectal and ovarian cancer. Monochromosome transfer experiments into colorectal tumour cell lines have provided functional evidence for a tumour suppressor gene located at 8p22-23. One of the genes from this region that is expressed by our suppressed hybrids is a candidate tumour suppressor gene, DLC1 (deleted in liver cancer), which has homology to rat RhoGAP. We have delineated the structure of the DLC1 gene and used single-stranded conformation polymorphism analysis (SSCP) to look for sequence variants in 126 colorectal and 33 ovarian primary tumours and cell lines. One exonic missense mutation and three intronic insertions/deletions were identified in primary colorectal tumours, as well as many polymorphisms present in germline DNAs. The rarity of exonic missense mutations, and the absence of protein-truncating mutations, indicates that DLC1 is not the target of 8p LOH in colorectal or ovarian tumours. The delineation of the gene structure allows mutation analysis of DLC1 in other tumour types for which it remains a candidate tumour suppressor gene based on its location and homology to rhoGAP.

5' Untranslated Regions↗
PubMed2000

[Blood transfusion audit methodology: the auditors, reference systems and audit guidelines].

The audit has become an essential aspect of the blood transfusion sector, and is a management tool that should be used judiciously. The main types of audit that can be envisaged in blood transfusion are the following: operational audit concerning a predetermined activity; systems quality audit; competence audit, combining the operational audit on a specific activity with quality management, e.g., laboratory accreditation; audit of the environmental management system; and social audit involving the organization of an activity and the management of human resources. However, the main type of audit considered in this article is the conformity audit, which in this context does not refer to internal control but to conformity with an internal guideline issued by the French National Blood Service. All audits are carried out on the basis of a predescribed method (contained in ISO 10 011). The audit is a system of investigation, evaluation and measurement, and also a means of continuous assessment and therefore improvement. The audit is based on set guidelines, but in fact consists of determining the difference between the directions given and what has actually been done. Auditing requires operational rigor and integrity, and has now become a profession in its own right.

Blood Banks↗