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T Higgins

Publications and source records attributed to T Higgins.

At least 19 recordsLinked to original sources
PubMed2002

Osteoid osteoma of the distal humerus mimicking tennis elbow.

Osteoid osteoma is an uncommon bony neoplasm which rarely occurs in the elbow region. We present a case in a sixteen year old male whose symptoms were suggestive of lateral epicondylitis, or tennis elbow, and he had been treated as such for a period of eighteen months. CT scan and isotope bone scan showed typical features of osteoid osteoma and his symptoms resolved rapidly following excision of the lesion. Tennis elbow is rare in the adolescent age group, and other diagnoses should be excluded in cases where the clinical findings are suggestive of this condition.

Adolescent↗
PubMed2001

Eradication of established tumors by vaccination with Venezuelan equine encephalitis virus replicon particles delivering human papillomavirus 16 E7 RNA.

The etiological role of human papillomaviruses (HPV) in cervical and other cancers suggests that therapeutic vaccines directed against requisite viral antigens may eradicate tumors or their precursors. A Venezuelan equine encephalitis (VEE) alphavirus vector delivering the HPV16 E7 RNA was evaluated for antitumor efficacy using a murine E7+ tumor model. Vaccination with VEE replicon particles expressing E7 (E7-VRP) induced class I-restricted CD8+ T-cell responses as determined by IFN-gamma enzyme-linked immunospot (ELISPOT), tetramer, and cytotoxicity assays. E7-VRP vaccination prevented tumor development in all of the mice and effectively eliminated 7-day established tumors in 67% of tumor-bearing mice. The induction of protective T-cell responses was dependent on CD8+, but not CD4+ T cells. Long-lasting T-cell memory responses developed in E7-VRP-vaccinated mice as determined by complete protection from tumor challenge 3 months after the final vaccination. These promising results highlight the potent CD8+ T-cell-mediated antitumor effects elicited by VEE replicon-based vectors and support their further development toward clinical testing against cervical intraepithelial neoplasia or carcinoma.

Animals↗
PubMed2001

Isolation and characterization of a thermostable endo-beta-glucanase active on 1,3-1,4-beta-D-glucans from the aerobic fungus talaromyces emersonii CBS 814.70.

A novel endoglucanase active on 1,3-1,4-beta-D-glucans was purified to apparent homogeneity from submerged cultures of the moderately thermophilic aerobic fungus Talaromyces emersonii CBS 814.70. The enzyme is a single subunit glycoprotein with M(r) and pI values of 40.7 +/- 0.3 kDa and 4.4, respectively, and an estimated carbohydrate content of 77% (w/w). The purified beta-glucanase displayed activity over broad ranges of pH and temperature, yielding respective optima values of pH 4.8 and 80 degrees C. This enzyme was markedly thermostable with 15% of the original activity remaining after incubation for 15 min at 100 degrees C. Substrate specificity studies revealed the identity of the enzyme to be a 1,3-1,4-beta-D-glucanase. Identical K(m) values (13.38 mg.ml(-1)) were obtained with lichenan and BBG, while the V(max) value with lichenan (142.9 IU.mg(-1)) was approximately twice the value obtained with BBG (79.3 IU.mg(-1)). Time-course hydrolysis of barley-beta-glucan did not proceed linearly with respect to time indicating an 'endo' or more processive action for the enzyme. HPAEC fractionation of the products of hydrolysis yielded a range of oligosaccharides, with cellobiose, cellotriose and cellotetraose being the predominant oligosaccharide products.

Journal Article↗
PubMed2001

Defined flanking spacers and enhanced proteolysis is essential for eradication of established tumors by an epitope string DNA vaccine.

Loss of immunogenic epitopes by tumors has urged the development of vaccines against multiple epitopes. Recombinant DNA technologies have opened the possibility to develop multiepitope vaccines in a relatively rapid and efficient way. We have constructed four naked DNA-based multiepitope vaccines, containing CTL, Th cell, and B cell epitopes of the human papillomavirus type 16. Here we show that gene gun-mediated vaccination with an epitope-based DNA vaccine protects 100% of the vaccinated mice against a lethal tumor challenge. The addition of spacers between the epitopes was crucial for the epitope-induced tumor protection, as the same DNA construct without spacers was significantly less effective and only protected 50% of the mice. When tested for therapeutic potential, only the epitope construct with defined spacers significantly reduced the size of established tumors, but failed to induce tumor regression. Only after targeting the vaccine-encoded protein to the protein degradation pathway by linking it to ubiquitin, the vaccine-induced T cell-mediated eradication of 100% of 7-day established tumors in mice. The finding that defined flanking sequences around epitopes and protein targeting dramatically increased the efficacy of epitope string DNA vaccines against established tumors will be of importance for the further development of multiepitope DNA vaccines toward clinical application.

Adjuvants, Immunologic↗
PubMed2000

Patient characteristics and ICU organizational factors that influence frequency of pulmonary artery catheterization.

CONTEXT: Hemodynamic monitoring of patients with a pulmonary artery catheter is controversial because there are few data confirming its effectiveness, and patient and intensive care unit (ICU) organizational factors associated with its use are unknown. OBJECTIVE: To determine pulmonary artery catheter use in relationship to type of ICU organization and staffing, and patient characteristics, including severity of illness and insurance coverage. DESIGN, SETTING, AND PATIENTS: Retrospective database study of 10,217 nonoperative patients who received treatment at 34 medical, mixed medical and surgical, and surgical ICUs at 27 hospitals during 1998 (patients were enrolled in Project IMPACT). MAIN OUTCOME MEASURES: Pulmonary artery catheter use based on severity of illness measured by the Simplified Acute Physiology Score, resuscitation status at ICU admission, and ICU organizational variables, including type, size, and model. RESULTS: A pulmonary artery catheter was used for 831 patients (8.1%) in the ICU. In multivariate analysis adjusted for severity of illness, age, diagnosis, and do-not-resuscitate status, full-time ICU physician staffing was associated with a two-thirds reduction in the probability of catheter use (odds ratio [OR], 0.36; 95% confidence interval [CI], 0.28-0.45). Higher catheter use was associated with white race (OR, 1.38; 95% CI, 1.10-1.72) and private insurance coverage (OR, 1.33; 95% CI, 1.10-1.60). Admission to a surgical ICU was associated with a 2-fold increase in probability of catheter use (OR, 2.17; 95% CI, 1.70-2.76) compared with either medical or mixed medical and surgical ICUs. CONCLUSION: Organizational characteristics of ICUs, insurance reimbursement, and race, as well as clinical variables, are associated with variation in practice patterns regarding pulmonary artery catheter use. Understanding such influences, combined with studies measuring clinical and economic outcomes, can contribute to the development of policies for the rational use of pulmonary artery catheters. JAMA. 2000;283:2559-2567

Adult↗
PubMed1999

Effects of DNA immunization formulated with bupivacaine in murine and guinea pig models of genital herpes simplex virus infection.

The immunogenicity and efficacy of a herpes simplex virus type 2 glycoprotein D (gD2) DNA vaccine formulated with bupivacaine was evaluated using murine and guinea pig models of genital herpes. Animals received three doses of 100 microg of gD2 plasmid or control plasmid intramuscularly prior to intravaginal challenge with HSV-2. Immunization induced HSV ELISA and neutralizing antibody in serum and ELISA antibody in the vaginal secretions of all animals evaluated. Following intravaginal HSV-2 challenge, vaginal viral replication was reduced in both models with peak reductions of greater than 99%. Immunization also decreased the number of animals developing any clinical disease (p < 0.001) and the severity of the acute disease (total lesion score 6.4 versus 0.6 in guinea pigs, p < 0.001). Further recurrent lesion days were reduced from 14.5 to 4.9 days in immunized guinea pigs (p < 0.001). DNA immunization with gD2 + bupivacaine was effective in reducing clinical disease and viral replication in both guinea pigs and mice.

Animals↗
PubMed1999

Both AP-1 and Cbfa1-like factors are required for the induction of interstitial collagenase by parathyroid hormone.

PTH is a major regulator of calcium homeostasis by mobilizing calcium through bone resorption. We show that the expression of collagenase-3 (MMP-13), a member of the family of matrix metalloproteinases, required for the cleavage of collagens in the bone, is increased upon PTH injection in mice. A cis-acting element in the collagenase-3 promoter was identified which, together with AP-1, is required for induction by PTH. This element contains CCACA motifs which are required for binding of the 65 kDa osteoblast-specific splice variant of Cbfal. Introduction of mutations in this binding site that interfere with protein interaction also eliminates PTH inducibility and transactivation by Cbfa/ Runt proteins. While DNA binding activity of AP-1 is increased upon PTH treatment, high basal level of Cbfa/Runt binding activity is detectable in untreated cells which is not further increased by PTH, suggesting that AP-1 and Cbfal contribute to transcriptional activation through different mechanisms. In agreement with the critical role of both proteins defined in tissue culture cells, expression of collagenase-3 is reduced in mice lacking c-fos and is completely absent in cbfa1-/-embryos. These data provide the first evidence for a critical role of Cbfal, a major regulator of bone development, in PTH-dependent processes such as bone resorption.

Animals↗
PubMed1999

Three-dimensional spiral CT scanning in children with acute torticollis.

Three-dimensional spiral CT scanning is now becoming a common investigation in children who have a history of acute torticollis. In the last year, 21 consecutive children who came to our unit with a history of acute torticollis were assessed using standard plain radiographs and a 3-dimensional spiral CT scan. Ten patients had a history of recent trauma. Spiral CT scanning revealed that 13 children had atlanto-axial rotatory subluxation (AARS). Plain radiographs had only a sensitivity of 33% and specificity of 71% in detecting AARS. Sixteen children were treated using a Halter traction. Four failed to resolve clinically and were put on a halo traction after 3-dimensional CT scanning again confirmed residual AARS. Two children remained symptomatic after halo traction, with persisting rotatory and anterior subluxation on repeat spiral CT. They both underwent a posterior in-situ fusion, with no attempt at open reduction. Plain radiography is limited in investigating acute torticollis in children. Spiral 3-dimensional CT reconstruction has an important role to play in both the investigation and management of children who present with acute torticollis.

Acute Disease↗
PubMed1998

DNA vaccination with HIV-1 expressing constructs elicits immune responses in humans.

Humoral and cellular immune responses have been produced by intramuscular vaccination with DNA plasmids expressing HIV-1 genes, suggesting possible immunotherapeutic and prophylactic value for these constructs. Vaccination with these constructs has decreased HIV-1 viral load in HIV-1-infected chimpanzees. In addition, naive (i.e. non-HIV-1-infected) chimpanzees were protected against a heterologous challenge with HIV-1. Ongoing phase I clinical trials show that therapeutic vaccinations indeed boost anti-HIV-1 immune responses in humans. A therapeutic phase I trial on humans with these constructs induced a good safety profile and also demonstrated an immunological potentiation. These findings indicate that further studies with these constructs in humans are warranted.

AIDS Vaccines↗
PubMed1997

Differential control of cyclins D1 and D3 and the cdk inhibitor p27Kip1 by diverse signalling pathways in Swiss 3T3 cells.

Quiescent Swiss 3T3 cells can be induced to re-enter the cell cycle by stimulation of a variety of growth factor-dependent signal transduction cascades. We have utilised this cell system to investigate the point of convergence of mitogenic signalling by analysing the changes that distinct mitogens induce in the components of the cell cycle regulatory machinery (the G1 cyclins, cdks and their inhibitors). In the presence of insulin, activation of cAMP-dependent protein kinase caused a dramatic post-transcriptional down-regulation of p27(Kip1), an increase in cyclin D3 but had little effect on cyclin D1 levels, whilst activation of protein kinase C had a more modest effect on cyclin D3 and p27(Kip1) but caused a striking elevation in the expression of cyclin D1. The neuropeptide bombesin, when combined with insulin, caused increased expression of cyclin D1 and down-regulation of p27(Kip1) mRNA and protein. Thus each combination of mitogenic agents had different effects on the components responsible for regulating the orderly progression of the cell cycle. This outcome is incompatible with a single route to mitogenesis and demonstrates that different mitogens remain distinct in the signalling responses they initiate, only converging at the levels of the expression of the D-type cyclins and the inhibitor p27(Kip1).

3T3 Cells↗
PubMed1997

[D-Arg1,D-Trp5,7,9,Leu11]substance P: a novel potent inhibitor of signal transduction and growth in vitro and in vivo in small cell lung cancer cells.

[D-Arg1,D-Trp5,7,9,Leu11]Substance P (SP) was identified out of a panel of novel SP analogues as the most potent inhibitor of small cell lung cancer (SCLC) cell growth. This analogue inhibited proliferation of H-510 and H-69 SCLC cells in liquid culture and in semisolid media (IC50, 5 microM). Colony formation stimulated by multiple neuropeptides, including vasopressin and bradykinin, was also blocked by [D-Arg1,D-Trp5,7,9,Leu11]SP. This new SP analogue inhibited vasopressin- or bradykinin-induced Ca2+ mobilization and mitogen-activated protein kinase activation. Administration of [D-Arg1,D-Trp5,7,9,Leu11]SP inhibited the growth of an H-69 xenograft in nude mice. Our results support the hypothesis that SP analogue broad-spectrum neuropeptide antagonists could be of therapeutic value in SCLC.

Animals↗
PubMed1996

[D-Arg1,D-Trp5,7,9,Leu11]Substance P coordinately and reversibly inhibits bombesin- and vasopressin-induced signal transduction pathways in Swiss 3T3 cells.

The novel substance P (SP) analogue, [D-Arg1,D-Trp5,7,9,Leu11]SP like [D-Arg1,D-Phe5,D-Trp7,9,Leu11]SP inhibited DNA synthesis induced by bombesin, vasopressin, and bradykinin, but did not interfere with the mitogenic response induced by other growth factors or pharmacological agents in Swiss 3T3 cells. [D-Arg1,D-Trp5, 7,9,Leu11]SP reversibly inhibited bombesin-induced DNA synthesis, causing a 6-fold greater rightward shift in the bombesin dose response than [D-Arg1,D-Phe5,D-Trp7,9,Leu11]SP at identical concentrations (10 microM). We found that the new, more potent, SP analogue coordinately and reversibly inhibited bombesin-induced Ca2+ mobilization and protein kinase C (PKC) and mitogen-activated protein (MAP) kinase activation. The dose-response curves for bombesin-induced Ca2+ mobilization and MAP kinase activation were similarly displaced (51- and 40-fold, respectively) by [D-Arg1, D-Trp5,7,9,Leu11]SP. In addition, [D-Arg1,D-Trp5,7,9,Leu11]SP reversibly inhibited bombesin-induced tyrosine phosphorylation of Mr 110,000-130,000 and 70,000-80,000 bands as well as p125 focal adhesion kinase. [D-Arg1,D-Trp5,7,9,Leu11]SP also reversibly and coordinately inhibited vasopressin-induced Ca2+ mobilization, PKC stimulation, MAP kinase activation, tyrosine phosphorylation, and DNA synthesis in Swiss 3T3 cells. Surprisingly, deletion of the terminal Leu of [D-Arg1,D-Phe5,D-Trp7,9,Leu11]SP to yield [D-Arg1, D-Phe5,D-Trp7,9]SP1-10 resulted in a selective loss of inhibitory activity of this analogue against bombesin- but not vasopressin-stimulated DNA synthesis, Ca2+ mobilization, and MAP kinase activation. Collectively, these results suggest that SP analogues act at the receptor level to coordinately and reversibly antagonize bombesin- or vasopressin-induced signal transduction in Swiss 3T3 cells.

3T3 Cells↗
PubMed1996

Metabolism of the broad-spectrum neuropeptide growth factor antagonist: [D-Arg1, D-Phe5, D-Trp7,9, Leu11]-substance P.

Broad-spectrum neuropeptide growth factor antagonists, such as [D-Arg1, D-Phe5, D-Trp7,9, Leu11]substance P (antagonist D) and [Arg6, D-Trp7,9, NmePhe8]substance P(6-11) (antagonist G), are currently being investigated as possible anti-tumour agents. These compounds are hoped to be effective against neuropeptide-driven cancers such as small-cell lung cancer. Antagonist D possesses a broader antagonistic spectrum than antagonist G and hence may be of greater therapeutic use. The in vitro metabolism of antagonist D has been characterised and the structures of two major metabolites have been elucidated by amino acid analysis and mass spectrometry. Metabolism was confined to the C-terminus where serine carboxypeptidase action produced [deamidated]-antagonist D (metabolite 1) and [des-Leu11]-antagonist D (metabolite 2) as the major metabolites. Biological characterisation of the metabolites demonstrated that these relatively minor changes in structure resulted in a loss of antagonist activity. These results provide some of the first structure-activity information on the factors that determine which neuropeptides these compounds inhibit and on the relative potency of that inhibition.

Amino Acid Sequence↗