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Heather Davis

Publications and source records attributed to Heather Davis.

9 recordsLinked to original sources

Macrocyclic ketone analogues of halichondrin B.

Structurally simplified macrocyclic ketone analogues of halichondrin B were prepared by total synthesis and found to retain the potent cell growth inhibitory activity in vitro, stability in mouse serum, and in vivo efficacy of the natural product.

Animals↗

The Consortium to Investigate Vascular Impairment of Cognition: methods and first findings.

BACKGROUND: The Consortium to Investigate Vascular Impairment of Cognition (CIVIC) is a Canadian, multi-centre, clinic-based prospective cohort study of patients with Vascular Cognitive Impairment (VCI). We report its organization and the impact of diagnostic criteria on the study of VCI. METHODS: Nine memory disability clinics enrolled patients and recorded their usual investigations and care. A case report form included all vascular dementia (VaD) individual criteria for each of four sets (National Institute of Neurological Disorders and Stroke (NINDS-AIREN), Alzheimer's Disease Diagnostic Treatment Centers (ADDTC), the ICD-10 Classification of Mental and Behavioural Disorders (ICD-10), and the Diagnostic and Statistical Manual of Mental Disorders (DSM-IV)) of consensus-based diagnostic criteria and for the Hachinski Ischemia Score (HIS). Investigators, having completed the case report form, were asked to make a clinical judgement about the cognitive diagnosis based on the best available information, including neuroimaging. RESULTS: Of 1,347 patients (mean age 72 years; 56% women), 846 (63%) were diagnosed with dementia and 324 (24%) were diagnosed with VCI. The proportion of patients diagnosed with VaD by the diagnostic criteria was: 23.9% (n = 322) by DSM-IV, 10.2% (n = 137) by HIS, 4.3% (n = 58) by ICD-10, 3.8% (n = 51) by ADTCC, and 3.6% (n = 48) by NINDS-AIREN. Judged against a clinical diagnosis of VaD, the sensitivity/specificity of each was: DSM-IV (0.77/0.80); HIS (0.41/0.92); ICD-10 (0.29/0.98); ADTCC (0.24/0.98); NINDS-AIREN (0.42/0.995). Compared with a clinical diagnosis of VCI, sensitivities were lower for the diagnostic criteria, reflecting the exclusion of patients who did not have dementia. CONCLUSIONS: Consensus-based criteria for VaD omit patients who do not meet dementia criteria that are modeled on Alzheimer's disease. Even for patients who do, the proportion identified with VaD varies widely. Criteria based on empirical analyses need to be developed and validated.

Adult↗

Vaccination with heat-killed leishmania antigen or recombinant leishmanial protein and CpG oligodeoxynucleotides induces long-term memory CD4+ and CD8+ T cell responses and protection against leishmania major infection.

CpG oligodeoxynucleotides (ODN) have potent effects on innate and adaptive cellular immune responses. In this report, the ability of CpG ODN to confer long-term immunity and protection when used as a vaccine adjuvant with a clinical grade of leishmanial antigen, autoclaved Leishmania major (ALM), or a recombinant leishmanial protein was studied. In two different mouse models of L. major infection, vaccination with ALM plus CpG ODN was able to control infection and markedly reduce lesion development in susceptible BALB/c and resistant C57BL/6 (B6) mice, respectively, up to 12 wk after immunization. Moreover, B6 mice immunized with ALM plus CpG ODNs were still protected against infectious challenge even 6 mo after vaccination. In terms of immune correlates of protection, ALM plus CpG ODN-vaccinated mice displayed L. major-specific T helper cell 1 and CD8+ responses. In addition, complete protection was markedly abrogated in mice depleted of CD8+ T cells at the time of vaccination. Similarly, mice vaccinated with a recombinant leishmanial protein plus CpG ODN also had long-term protection that was dependent on CD8+ T cells in vivo. Together, these data demonstrate that CpG ODN, when used as a vaccine adjuvant with either a recombinant protein or heat-killed leishmanial antigen, can induce long-term protection against an intracellular infection in a CD8-dependent manner.

Animals↗

Further evidence for a strong genetic influence on the development of autoimmune thyroid disease: the California twin study.

To determine the heritable component of Graves' disease (GD) more precisely, a disease survey questionnaire completed by 13,726 California-born twin pairs over the age of 37 years was used as the foundation of this study. On the basis of this survey, each member of pairs reporting a past diagnosis of GD was then sought for an extensive telephone interview to seek diagnostic confirmation. Successful diagnostic evaluation occurred in 108 cases, of which 99 affected twin pairs form the basis of this report. The results indicate that the estimated pairwise concordance for is 17% in monozygotic (MZ) twins, and 1.9% in dizygotic (DZ) twins, which are in close agreement with a recent report from a Danish twin population. Moreover, the reported 3.9% occurrence of GD found in the first-degree relatives of affected twin pairs supports these findings. In contrast, only 0.45% of all twins, 0.27% of the spouses of twins, and approximately 0.16% of the first-degree relatives of unaffected twins were reported to have GD. Additionally, among the unaffected MZ twins of patients with GD, 17% reported having chronic thyroiditis and 10% other nonthyroid autoimmune conditions such as lupus erythematosus, pernicious anemia, or idiopathic thrombocytopenic purpura. Thus, a genetic predisposition appears to be shared for both thyroid and some nonthyroid autoimmune diseases. While it seems that GD is a strongly and nonspecifically heritable condition, the relatively low level of twin concordance indicates that this disease likely requires a nonheritable etiologic determinant(s) as well.

Adult↗

Tick-borne relapsing fever caused by Borrelia turicatae.

Tick-borne relapsing fever manifests as relapsing episodes of fever with significant morbidity and mortality. We report a case of Borrelia turicatae disease in a 13-year-old male youth with outdoor exposures in Texas. After multiple clinic visits the diagnosis was made, and treatment was initiated. The patient did well without long term sequelae.

Adolescent↗

Increased ethanol self-administration and anxiety-like behavior during acute ethanol withdrawal and protracted abstinence: regulation by corticotropin-releasing factor.

BACKGROUND: Animal models of alcohol dependence suggest that long-term alterations in brain corticotropin-releasing factor (CRF) systems, key mediators of the behavioral stress response, may be involved in the development and reinstatement of dependence on drugs of abuse. The objective of the present study was to investigate the role of CRF in the regulation of ethanol self-administration and to examine the behavioral stress response during acute withdrawal and protracted abstinence. METHODS: Male Wistar rats were made dependent on ethanol via chronic exposure to ethanol vapor. Ethanol self-administration and exploratory behavior in the elevated plus maze were measured at 2 hr and 3 to 5 weeks after exposure. The role of CRF in ethanol self-administration was examined via central injection of the CRF receptor antagonist D-Phe-CRF(12-41). RESULTS: Rats showed increased responding for ethanol 2 hr and 3 to 5 weeks after chronic ethanol exposure, which was attenuated by central injection of D-Phe-CRF(12-41). In addition, rats displayed a decrease in open-arm exploration in the elevated plus maze when tested 2 hr and 4 weeks after exposure. CONCLUSIONS: These results indicate that chronic ethanol exposure leads to increased ethanol self-administration and decreased open-arm exploration in the elevated plus maze during acute withdrawal and protracted abstinence. Attenuation of ethanol self-administration via central injection of D-Phe-CRF(12-41) implicates CRF as an underlying mechanism regulating long-term motivational effects associated with alcohol dependence.

Alcohol Drinking↗

Gender Differences in Arithmetic Strategy Use: A Function of Skill and Preference.

This study was designed to examine whether first-grade boys' use of retrieval and first-grade girls' use of manipulatives reflected gender differences in their abilities to use these strategies or gender differences in preferences for strategy use. Eighty-four first-grade students, 42 boys and 42 girls, from two suburban elementary schools participated in this study. The children solved basic arithmetic problems under two conditions: a free-choice condition in which they were allowed to solve the problems any way they preferred and a game condition in which the children's strategy use was constrained so that all children used the same strategies on the same arithmetic problems. Strategy use during the free-choice session replicated the findings of earlier research indicating that girls tend to use strategies utilizing manipulatives and boys tend to use retrieval. During the game condition, when we controlled the types of strategies children used on different problems we found that boys were as able as girls to calculate solutions using manipulatives. Girls, however, were not as capable as boys in their retrieval of answers to arithmetic problems from memory. No differences were found in error rates or speed of retrieval. Gender differences were found in the variability of correct retrieval, with boys being significantly more variable than girls. Copyright 2001 Academic Press.

Journal Article↗