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Amy Jones

Publications and source records attributed to Amy Jones.

9 recordsLinked to original sources
PubMed2026

Development of a core descriptor set for studies assessing interventions for diabetes-related foot ulceration.

AIMS/HYPOTHESIS: Foot ulceration is a common complication of diabetes and is associated with high mortality and costs. The quality of evidence to inform clinical practice is limited, partly because clinical studies do not consistently report baseline participant characteristics. This study aimed to develop a core descriptor set (CDS), a minimum set of descriptors to be measured in all studies evaluating interventions for people with diabetes-related foot ulceration. METHODS: A longlist of descriptors was generated through a systematic review of studies assessing interventions for diabetes-related foot ulcers, pre-registered with PROSPERO (CRD42019128250). The identified descriptors were then ranked based on perceived importance by healthcare professionals from different fields and geographical locations using a nine-point Likert scale in the first round of a Delphi survey. Using standardised criteria, descriptors without consensus were re-ranked in round two. Critical descriptors and those without consensus after the Delphi process were discussed in the consensus meeting to finalise the CDS. RESULTS: The systematic review yielded 95 candidate descriptors. The two Delphi rounds were completed by 102 and 69 healthcare professionals, respectively. The Delphi process identified 34 critically important descriptors and 13 descriptors without consensus, which were discussed in the consensus meeting. The ratified CDS included 28 descriptors across nine domains: demographic variables; individual factors; ulcer characteristics; limb characteristics; ongoing medical interventions; previous surgical interventions; medication history; biochemical measurements; and quality of life/function/symptoms. CONCLUSIONS/INTERPRETATION: This CDS reflects characteristics important to health professionals and researchers when reporting clinical studies on diabetes-related foot ulceration. Its use will aid the reporting of future studies.

Humans↗
PubMed2006

Inhibition of p38 mitogen-activated protein kinase prevents inflammatory bone destruction.

Mitogen-activated protein kinase (MAPK) pathways are implicated in joint destruction in rheumatoid arthritis (RA) by modulating the production and functions of inflammatory cytokines. Although p38 MAPK (p38) participates in signaling cascades leading to osteolysis in arthritis, the mechanisms of its action in this process remain incompletely understood. Here, we found that the osteoclast (Ocl) precursors expressed p38alpha, but not p38beta, p38delta, and p38gamma isoforms. Treatment of these cells with receptor activator of nuclear factor (NF)-kappaB ligand (RANKL) resulted in p38 activation. Importantly, Ocl development induced by RANKL or RANKL and tumor necrosis factor (TNF)-alpha was blocked with the novel p38 inhibitor 4-(3-(4-chlorophenyl)-5-(1-methylpiperidin-4-yl)-1H-pyrazol-4-yl)pyrimidine (SC-409). To validate in vitro data, p38 role was further investigated in streptococcal cell wall (SCW)-induced arthritis in rats. We found that SCW-induced joint swelling and bone destruction were attenuated by SC-409. Mechanistically, the data show that SCW-stimulated DNA binding activity of the transcription factor myocyte-enhancing factor 2 C, which is downstream of p38, was inhibited by SC-409. In addition, SC-409 inhibited SCW-stimulated expression of numerous factors, including TNF-alpha, interleukin-1beta, and RANKL. Although c-Jun NH2-terminal kinase and NF-kappaB pathways were activated in vitro by RANKL and in vivo by SCW, SC-409 had no significant effect on these pathways. In conclusion, our data show that p38 modulates the production and signaling of cytokines, thus providing a mechanism of the bone-sparing effect of SC-409 in rat arthritis. These data present SC-409 as a novel potent p38 inhibitor and suggest that p38-based therapies may be beneficial in preventing bone loss associated with RA.

Animals↗
PubMed2005

Live, attenuated Salmonella typhimurium vectoring Campylobacter antigens.

We describe the evaluation of three live, attenuated deltaphoP/Q Salmonella enteric serovar Typhimurium strains expressing PEB1 minus its signal sequence (PEB1-ss) from three different plasmids: a pBR-based asd plasmid, an arabinose-based runaway plasmid, which each expressed PEB1-ss in the bacterial cytosol, and a PEB1::HlyA fusion plasmid that directs secretion of PEB1-ss into the extracellular milieu. Serum IgG responses specific for PEB1-ss were induced by pBR-derived and runaway plasmids, with 100 and 90% seroconversion, respectively, at a 1:500 dilution of anti-sera as measured by Western blot analysis, while the PEB1-ss::HlyA fusion plasmid induced serum IgG in only 20% of the mice. Although significant levels of anti-PEB serum IgG were induced, no protection against oral Campylobacter jejuni challenge was observed.

Administration, Oral↗
PubMed2004

Cryopreservation of metaphase II human oocytes effects mitochondrial membrane potential: implications for developmental competence.

BACKGROUND: Current outcome results with embryos derived from thawed MII human oocyes are significantly lower than with embryos cryopreserved at the pronuclear stage. Here, we investigated whether freezing-thawing was associated with changes in oocyte mitochondrial polarity (DeltaPsim) that could influence competence by altering ATP levels or the ability of the cytoplasm to regulate intracellular Ca2+. METHODS: Fresh and thawed uninseminated and unfertilized MII oocytes were stained with the DeltaPsim-specific probe JC-1 to detect clusters of high-polarized mitochondria (J-aggregate positive) and with the Ca2+- specific probe Fluo-4 to measure changes in intracellular levels of this cation. ATP content per oocyte was measured directly and cortical granules were visualized with a cortical granule-specific probe. RESULTS: A significant difference between fresh and thawed MII oocytes existed for pericortical J-aggregate fluorescence and for the ability of the cytoplasm to increase free Ca2+ in response to ionophore exposure. No significant difference in ATP contents was measured and cryopreservation was not associated with an apparent release of cortical granules. CONCLUSION: Irreversible loss of high DeltaPsim in thawed oocytes may be associated with defects in Ca2+ signalling after insemination and could have downstream consequences for normal embryogenesis.

Adenosine Triphosphate↗
PubMed2004

H(2) production and carbon utilization by Thermotoga neapolitana under anaerobic and microaerobic growth conditions.

H(2) production by Petrotoga miotherma, Thermosipho africanus, Thermotoga elfii, Fervidobacterium pennavorans, and Thermotoga neapolitana was compared under microaerobic conditions. Contrary to these previously reported strains being strict anaerobes, all tested strains grew and produced H(2) in the presence of micromolar levels of O(2). T. neapolitana showed the highest H(2) production under these conditions. Microscopic counting techniques were used to determine growth curves and doubling times, which were subsequently correlated with optical density measurements. The Biolog anaerobic microtiter plate system was used to analyze the carbon source utilization spectrum of T. neapolitana and to select non-metabolized or poorly metabolized carbohydrates as physiological buffers. Itaconic acid was successfully used as a buffer to overcome pH-induced limitations of cell growth and to facilitate enhanced production of CO-free H(2).

Aerobiosis↗
PubMed2003

Advancing End-of-Life Care: lessons learned from a statewide panel.

The Florida Panel for the Study of End-of-Life Care was an innovative and effective approach to the formulation of end-of-life (EOL) policy recommendations that significantly influenced the legislative process and resulted in new EOL legislation. The lessons from this panel's experience are useful to other states considering legislative changes in their EOL policies. Key to the success of the EOL panel was its heterogeneous membership that allowed the collaboration of policy makers, clinicians, ethicists, citizens, and other stakeholders. Also, crucial to the success of the panel were the dimensions of the deliberative process embraced by the panel. This process supported an impressive level of mutual respect, trust, and openness among the panel members that, with only minor exceptions, allowed the members of the panel to rise above the parochial political battles that have often preempted serious debate on controversial EOL issues. The recommendations of the EOL panel led to new state laws on EOL care and improvements in public awareness, professional education, and clinical protocols for implementing patients' wishes. Another major but largely unforeseen consequence of the EOL panel was the development of significant new working alliances among members and organizations. These alliances led to new projects on EOL care and have significantly improved communication and working relationships between organizations and individuals committed to improving EOL care.

Florida↗
PubMed2003

Selective cyclooxygenase-2 inhibition does not alter keratinocyte wound responses in the mouse epidermis after abrasion.

The cyclooxygenase isoforms, COX-1 and COX-2, are the rate limiting enzymes in the biosynthesis of prostaglandin E(2), a major prostaglandin involved in epidermal homeostasis and repair. Epidermal injury results in transient hyperplasia and induction of COX-2 expression. The role of COX-2 in this hyperplasia is unknown, however. In this study, we characterized the epidermal expression of COX isozymes following wounding by abrasion in SKH-1 mice using immunohistochemistry, in situ hybridization, and Western analysis. In addition, we evaluated pivotal keratinocyte functions necessary for the reparative hyperplasia, including proliferation by 5-bromo-2'deoxy-uridine labeling and differentiation by the expression of involucrin, keratin 1, and keratin 6. Although COX-1 expression in keratinocytes remained unchanged during wound healing, COX-2 expression was induced coincidentally with keratinocyte proliferation and keratin 6 expression, suggesting a role for COX-2 in epidermal repair. The role of COX-2 was also evaluated using the selective COX-2 inhibitor SC-791 and the traditional COX inhibitors indomethacin and diclofenac. Neither inhibitor altered keratinocyte proliferation or differentiation following abrasion, in contrast to dexamethasone, which delayed these responses. Our results indicated that, although COX-2 expression was coincident with transient epidermal hyperplasia and keratinocyte proliferation/differentiation during the healing of epidermal injury, it does not play a pivotal role in this repair process.

Animals↗
PubMed2002

Sensitization of lanthanides by nonnatural amino acids.

The sensitization of Eu(III) and Tb(III) by ethylenediaminetetraaceticacid (EDTA)-derivatized tryptophan (Trp), 7-azatryptophan (7AW) and 5-hydroxytryptophan (5HW) has been examined. These Trp analogs were utilized in the present study because they can be incorporated into proteins in place of native Trp residues and because they absorb strongly beyond 305 nm (where Trp absorbance goes to zero), allowing selective excitation of such species in the presence of other Trp-containing proteins. All three indole derivatives were able to sensitize Tb(III) luminescence, with the relative sensitization being in the order Trp > 5HW > 7AW. On the other hand, only the 7AW-EDTA complex was able to sensitize Eu(III) luminescence, likely owing to a better spectral overlap between 7AW emission and Eu(III) absorbance. The sensitized emission of Tb(III) and Eu(II) displayed the expected long emission lifetimes at 545 nm [for Tb(III)] and 617 nm [for Eu(III)], indicating that long-lifetime lanthanide emission could be produced using nonnatural amino-acid donors. Thus, 7AW- and 5HW-sensitized lanthanide emissions should prove to be useful in biophysical studies, such as the use of fluorescence energy transfer to probe biomolecular interactions in vivo.

Amino Acids↗