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Biomedical subjects

C S Jones

Publications and source records attributed to C S Jones.

At least 37 records · Page 2Linked to original sources
PubMed2000

Profiling of changes in gene expression during raspberry (Rubus idaeus) fruit ripening by application of RNA fingerprinting techniques.

Processes that contribute to the overall phenomenon of fruit ripening are not well understood for many soft fruit species, including raspberry (Rubus idaeus L.) Recent biochemical data implicate ethylene and a range of cell wall hydrolases in ripening processes. However, the genes encoding these activities, and others related to ripening, remain to be characterised. With the advent of high-throughput RNA-fingerprinting techniques it is possible to characterise rapidly the changes in gene expression during developmental processes. This paper describes the application of two RNA-fingerprinting techniques (cDNA amplified fragment length polymorphism and differential display reverse transcription-polymerase chain reaction) to the ripening fruit of Rubus idaeus. Copy-DNA tags were isolated representing 34 genes, up-regulated during fruit ripening. The expression profiles of these genes were determined by RNA-blot analysis and their sequences were compared with those in public databases. Potential roles for some of these gene products are considered, providing valuable insights into the processes that underpin fruit ripening. Many of the cDNAs isolated in this study provide tools for the biotechnological improvement of fruit quality.

Animals↗
PubMed2000

Epidemiology of personal watercraft-related injury on Arkansas waterways, 1994-1997: identifying priorities for prevention.

Personal watercraft (PWC) use has increased rapidly in the past ten years. Consequences of the increased use are collisions and injuries. This study was conducted to determine the etiology and the characteristics surrounding PWC collisions and injury associated with the use of these popular water recreational vehicles and determine countermeasures. Methods included obtaining boating accident reports limited to PWCs from the Arkansas Game and Fish Commission for the years 1994 through 1997. Results show that there were 126 incidents involving 141 vessels and over $156,000 (US) in property damage. Almost two-fifths of PWC users were injured, mainly head trauma and fractures to the lower limbs. There were five reported fatalities. Study suggests that PWC collisions and injury are increasing. With increased use and popularity, this trend will continue unless sustained efforts in prevention are established. Changes in policy, education and manufacturing standards need to be considered and initiated to provide for safe PWC operation and boating environment.

Accidents↗
PubMed2000

Use of differential display to detect changes in gene expression in the intermediate snail host Biomphalaria glabrata upon infection with Schistosoma mansoni.

Changes in gene expression in Biomphalaria glabrata following infection with Schistosoma mansoni have been investigated using a modified differential display approach. RNA was extracted from ovotestis, mantle tissue and anterior nephridium of control and exposed snails at 2 time-points (4 h and 24 h) post-exposure and analysed by RNA fingerprinting. A number of transcripts were identified; some novel and some homologous to mRNAs in GenEMBL that were previously unknown in B. glabrata. Down regulation of one 241 bp mRNA expressed sequence fragment - with an open reading frame showing 48% identity to a cytochrome p450 over 80 residues - has been confirmed using semi-quantitative RT-PCR. Preliminary classification of B. glabrata cyp450 sequence shows it to fall into CLAN 2 of the cytochrome p450 superfamily. Differential display has been successful in identifying changes in gene expression in Biomphalaria glabrata upon infection with Schistosoma mansoni and promises to be a useful technique for the investigation of the interaction between host and parasite.

Animals↗
PubMed2000

Late onset of accessory pathway conduction in a patient with complete AV block.

This case report discusses a patient with complete AV block in early childhood. The patient required a permanent pacemaker. At 6 years of age, intermittent preexcited beats were noted on telephonic transmissions. At 7 years of age, 1:1 preexcitation was noted in sinus rhythm. Therefore, late onset of antegrade accessory pathway function is demonstrated. This case provides evidence of developmental changes in accessory pathways. This may explain age related differences in the onset of narrow complex tachycardia in the school age years.

Age of Onset↗
PubMed1999

Retinoic acid increases tyrosine phosphorylation of focal adhesion kinase and paxillin in MCF-7 human breast cancer cells.

Treatment of estrogen receptor (ER)-positive MCF-7 human breast cancer cells with retinoic acid (RA) inhibited cell growth and increased cell adhesion to fibronectin. In contrast, ER- MDA-MB-231 cells failed to respond. Western blot analysis showed that tyrosine phosphorylation of two major bands at Mr 125,000 and Mr 68,000 was induced by RA in ER+ MCF-7 human breast carcinoma cells. However, this induction was a late phenomenon detectable at 12 and 24 h, but not within 3 h. A similar increase of tyrosine phosphorylation by RA was observed in ER+ human breast cancer cell lines T-47D and ZR-75-1, but not in the ER- cell lines MDA-MB-231, MDA-MB-453, and MDA-MB-468. Focal adhesion kinase and paxillin, which localize in focal adhesion plaques and may play important roles in the integrin signaling pathway, were identified as the major proteins showing RA-induced tyrosine phosphorylation. The retinoid X receptor-selective compound SR11237 failed to induce tyrosine phosphorylation, indicating that retinoid X receptor activation is not involved in this phenomenon. In contrast, stable overexpression of a truncated RA receptor (RAR) alpha cDNA, RARalpha403, with strong RAR dominant negative activity prevented the increase in tyrosine phosphate, suggesting that RAR signaling is involved in RA-induced tyrosine phosphorylation. Tyrosine phosphorylation was induced the most by the RAR-alpha (193836), followed by RAR-gamma (194433), but was not significantly induced by RAR-gamma (193174)-selective retinoids. This study demonstrates a coordinated albeit relatively late effect of RA on cell adhesion and tyrosine phosphorylation in ER+ human breast cancer cells and suggests RAR-alpha as the major responsible retinoid receptor.

Antineoplastic Agents↗
PubMed1999

Drowning among personal watercraft passengers: the ability of personal flotation devices to preserve life on Arkansas waterways, 1994-1997.

Personal flotation devices (PFD) are promoted and in many states are required for safe boating practices and to prevent drowning. Primary use of PFDs is associated with water sports (water skiing, tubing, etc.), boating and other water activities. Their purpose is to preserve life and prevent drowning. However, their effectiveness to prevent drowning and near-drowning has not been well established. The purpose of this investigation was to determine the effectiveness of PFDs to prevent drowning and near-drowning of individuals involved in personal watercraft (PWC) crashes. Methods include the 48-month collection of PWC crash data from the Arkansas Game and Fish Commission for 1994-1997. Information on PFD use, swimming experience, whether passengers were ejected from the watercraft and crash cause was queried. Results show that 38% were not swimmers, 98% wore a PFD and 54% were ejected from the PWC. Alcohol was a causal factor in six crashes and one death. It is estimated that PFDs saved 38 Arkansans who could have drowned. This study highlights one example of the effectiveness of PFDs to prevent mortality and morbidity.

Accidents↗
PubMed1998

Screening for high-affinity ligands to the Src SH2 domain using capillary isoelectric focusing-electrospray ionization ion trap mass spectrometry.

A solution-based microscale approach for determination of high-affinity noncovalent complexes from mixtures of compounds is presented, based on capillary isoelectric focusing coupled on-line with electrospray ionization ion trap mass spectrometry. The studies are performed using the src homology 2 domain and tyrosine-phosphorylated peptide ligands as a model system. Tight complexes are formed in solution, preconcentrated up to 2 orders of magnitude and separated on the basis of their isoelectric points. The complexes are then dissociated in the mass spectrometer and the freed ligands identified. Picomole or less amounts of protein reagent are consumed per experiment. Structural information for the ligands involved in tight complex formation may be obtained using the MSn capabilities of the ion trap. The methodology can potentially be used to screen rapidly combinatorial mixtures of compounds for high-affinity ligands.

Electrophoresis, Capillary↗
PubMed1998

Structure-based design of cathepsin K inhibitors containing a benzyloxy-substituted benzoyl peptidomimetic.

Peptidomimetic cathepsin K inhibitors have been designed using binding models which were based on the X-ray crystal structure of an amino acid-based, active site-spanning inhibitor complexed with cathepsin K. These inhibitors, which contain a benzyloxybenzoyl group in place of a Cbz-leucine moiety, maintained good inhibitory potency relative to the amino acid-based inhibitor, and the binding models were found to be very predictive of relative inhibitor potency. The binding mode of one of the inhibitors was confirmed by X-ray crystallography, and the crystallographically determined structure is in close qualitative agreement with the initial binding model. These results strengthen the validity of a strategy involving iterative cycles of structure-based design, inhibitor synthesis and evaluation, and crystallographic structure determination for the discovery of peptidomimetic inhibitors.

Benzoates↗
PubMed1998

Cynomolgus monkey (Macaca fascicularis) cathepsin K: cloning, expression, purification, and activation.

Methodology for the production of recombinant active cynomolgus monkey (Macaca fascicularis) cathepsin K (EC 3.4.22.38) was elucidated. The cDNA encoding the cathepsin K was cloned from female M. cynomolgus monkey mRNA. The deduced amino acid sequence of M. cynomolgus preprocathepsin K from the cDNA sequence showed 94.2% identity to human preprocathepsin K. Sequence differences occurred only in the prepro- domains; the mature domains were identical. The recombinant M. cynomolgus cathepsin K was expressed as a secreted proenzyme using baculovirus-infected SF21 insect cells having the predicted N-terminus (LYPEEILDTH ellipsis ), indicating proper cleavage of the secretion sequence. Purified monkey procathepsin K was activated under autocatalytic conditions at pH 4.0. The mature enzyme was composed of mixture of enzymes having N-termini of Gly113 and Arg114. The molecular weight was determined to be 23,668.3 Da by MALDI-TOF-MS which is consistent with the absence of carbohydrate on the mature enzyme. These results indicate that monkey procathepsin K is able to autoactivate and produces a mature enzyme which is identical to that of human cathepsin K. Since the sequence of monkey and human mature cathepsin K are identical and the in vitro activation mechanisms appear to be indistinguishable, monkeys are predicted to be a good animal model for evaluating cathepsin K inhibitors in vivo as therapeutic agents for diseases characterized by excessive bone loss, such as osteoporosis.

Amino Acid Sequence↗
PubMed1998

Are newspapers a viable source for intentional injury surveillance data?

BACKGROUND: Previous researchers have reported that newspapers were useful adjuncts to unintentional injury surveillance efforts in a nearby southern state. The current study sought to determine whether newspaper accounts of intentional injuries could provide a reliable source of primary or secondary surveillance data. METHODS: Newspaper accounts of assaults, homicides, suicides, and rapes occurring in Jefferson County, Alabama, between January 1, 1991, and December 31, 1991, were compared with similar data from official governmental agencies whose responsibility it is to investigate and/or document the occurrence, details, and characteristics of violent events resulting in death or injury. RESULTS: Newspapers greatly underreported suicides, rapes, and assaults, and reported firearms-related incidents in numbers that substantially exceeded their actual occurrence. CONCLUSIONS: Much information of potential value for injury surveillance purposes appears to be excluded from newspapers by editorial process and policy. Thus, newspapers are neither a valid nor reliable source for intentional injury surveillance purposes.

Alabama↗