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K O'Connell

Publications and source records attributed to K O'Connell.

At least 19 recordsLinked to original sources
PubMed2006

Pulsed-field gel electrophoresis of Campylobacter jejuni sheep abortion isolates.

Campylobacter species are a significant cause of sheep abortion in most sheep-raising countries. In New Zealand, Campylobacter fetus subsp. fetus is the leading cause of diagnosed sheep abortion and the species C. jejuni and C. coli have also been implicated. To date, strain typing information of C. jejuni sheep abortion isolates is limited. The objective of the present study was to genotype C. jejuni isolates cultured from sheep abortions submitted to diagnostic laboratories in New Zealand during the 2000 breeding season, using pulsed-field gel electrophoresis (PFGE). In this study, C. jejuni isolates were cultured from approximately 10% of farms from which Campylobacter species were isolated from sheep abortions in the year 2000. This equated to 25 C. jejuni isolates from 21 farms. These isolates were obtained from the veterinary diagnostic laboratories and strain typed using the molecular typing technique PFGE. Ten distinct PFGE types were identified amongst the isolates. No particular PFGE type was found most frequently amongst these C. jejuni sheep abortion isolates. However, indistinguishable or similar C. jejuni PFGE types were identified from different aborted foetuses from the same flock, consistent with the role of C. jejuni as an infectious cause of abortion in sheep. These strain types were similar or indistinguishable from C. jejuni sheep abortion isolates obtained in 1999 in a smaller study (Mannering, S.A., Marchant, R.M., Middelberg, A., Perkins, N.R., West, D.M., Fenwick, S.G., 2003. Pulsed-field gel electrophoresis typing of C. fetus subsp. fetus from sheep abortions in the Hawke's Bay region of New Zealand. NZ Vet. J. 51, 33-37).

Abortion, Veterinary↗
PubMed2003

Preliminary development of the World Health Organsiation's Quality of Life HIV instrument (WHOQOL-HIV): analysis of the pilot version.

The assessment of quality of life (QoL) is central to understanding how people's lives are affected by HIV infection. A reliable and valid measurement tool developed for cross-cultural use will be important in evaluating the global impact of the disease. This paper reports on the development and preliminary assessment of the WHOQOL-HIV pilot instrument that is designed for use with the WHOQOL-100 for persons living with HIV and AIDS (PLWHA). In this study, 900 people with a mean age of 32 from six culturally diverse sites completed the WHOQOL-100 along with 115 HIV specific items. Respondents were HIV asymptomatic (23%), HIV symptomatic (23%), had AIDS (20%) or were well (34%). Analyses to select the best items from the piloted instrument resulted in the inclusion of 33 items covering 12 new facets for a field trial version of the WHOQOL-HIV instrument; e.g. symptoms of HIV, body image, social inclusion, death and dying, and forgiveness. The results indicate excellent internal consistency for the scale (alpha=0.98) and its domains (alpha=0.87-0.94). For PLWHA, pain and discomfort, positive feelings, dependence on medication, sexual activity, financial resources and spiritual connection were particularly poor, indicating that the severest impact of HIV extends beyond physical well-being to the psycho-social-spiritual and environmental areas of QoL. Comparisons using ANOVA showed that persons who are at later stages of HIV infection, or are currently ill report poorer QoL than those that were well (p<0.01). Women report poorer QoL than men for almost every facet (p<0.01) and older persons (>30) reported lower negative feelings, and better social inclusion, spiritual connection, forgiveness and spiritual experience than younger persons. Finally, those with no education, or only primary education showed some of the poorest means. It is concluded that these new items and facets add value for measurement of QoL in PLWHA.

Acquired Immunodeficiency Syndrome↗
PubMed2001

Isotype-specific antibody responses of cattle to Salmonella Dublin lipopolysaccharide and porin following Salmonella Dublin vaccination and acute and chronic infection.

Stimulation of different T-cell subsets during antigen presentation influences the antibody isotype response to an antigen. Salmonella infection and Salmonella bacterin vaccination are likely to stimulate different T-cell subtypes. The objective of this study was to determine whether there are differences in the isotype response of cattle to Salmonella antigens following Salmonella infection and Salmonella bacterin vaccination. Sera from Salmonella bacterin-vaccinated, experimentally infected, and chronically infected (carrier) adult cattle collected during previous studies was used to evaluate the IgG1, IgG2, and IgM isotype responses of cows to Salmonella serotype Dublin lipopolysaccharide (LPS) and porin. Following vaccination and experimental oral infection, IgG1 titers to LPS and porin rose more quickly and persisted longer than did IgG2 titers. In contrast to Salmonella infection, bacterin vaccination stimulated a weak response to Salmonella porin. Salmonella infection also induced a higher IgG2:IgG1 titer ratio to LPS than did bacterin vaccination. Chronic Salmonella infection induced the highest LPS and porin IgG2:IgG1 titer ratios and the highest correlation between LPS and porin titers. Response operating characteristic curves for each isotype-specific enzyme-linked immunosorbent assay (ELISA) were determined to evaluate the effect of isotype on the sensitivity and specificity of Salmonella ELISA serology for distinguishing sera of Salmonella carriers from those of vaccinated and acutely infected cows. IgG2 titers to LPS and porin provide a more specific indicator of chronic Salmonella infection status than do IgG1 titers to the same antigens with little to no loss in sensitivity.

Acute Disease↗
PubMed2000

An actigraphic comparison of sleep restriction and sleep hygiene treatments for insomnia in older adults.

We compared the efficacy of sleep restriction therapy combined with sleep hygiene, nap modification of sleep restriction therapy combined with sleep hygiene, and sleep hygiene alone as treatments for insomnia in 39 community-dwelling men and women 55 years and older. We used the wrist actigraph as an objective outcome measure for all subjects at baseline, end of treatment, and 3-month follow-up; polysomnography (PSG) was conducted in a subgroup of subjects. Although subjects appeared to follow restriction instructions through follow-up, we found few between-group differences in treatment efficacy. Lack of treatment effect might be explained by the efficacy of HYG as a treatment in itself and the relatively low symptom level in these healthy older poor sleepers. At baseline, actigraphic results were found to correlate more highly than sleep log data with PSG in our sample. Actigraphic total sleep time, in particular, was highly correlated with PSG.

Adult↗
PubMed1998

Overeating, reversal theory, and weight cycling.

America's overweight problem is universally recognized and escalating, despite billions of dollars spent to combat it. For the past century, a unidimensional paradigm was predominantly used to correct the overweight problem by reducing calories through dieting. As a result of the profound failure of traditional diet programs, a phenomenon known as weight cycling was born. In this article, a multidimensional paradigm is emphasized to address weight cycling. Reversal theory extends a new theoretical basis that can account for unpleasant feelings, or tension stress, as a trigger of overeating in women who weight cycle. A case example demonstrates how reversal theory explains overeating as a response to high-tension stress. Results of two studies are presented, describing overweight and normal-weight women's reversal theory states during self-reported episodes of overeating and resisting overeating. The multidimensional paradigm calls for emotional overeating behaviors to be addressed in weight management.

Adult↗
PubMed1996

Germ cell testis cancer: 15-year review.

Testis cancer affects 2-3 men per every 100,000 in the United States, making it the most common solid tumor of men in the 20-35-year-old age range. Since the average age of active duty military personnel is included in the age range of those at greatest risk for germ cell testis cancer, it is of pertinent clinical importance to physicians who treat these young patients. The National Naval Medical Center has been using cisplatin-based protocols since the time of their introduction. This study reviews the success of treating these patients and examines the treatment failures.

Adult↗
PubMed1996

Poorer prognosis in older patients with endometrial adenocarcinoma.

It has been suggested that there are two types of endometrial carcinoma: the first arises in younger women who have hyperestrogenism and has a favorable prognosis and the second occurs in older women, is not associated to estrogen stimulation, and has a poorer prognosis. This study examined the hypothesis that more aggressive carcinomas are found in older patients with no evidence of estrogen stimulation. A retrospective review of all patients (N = 82) with endometrial carcinoma diagnosed and treated at our institution between 1978 and 1990 was undertaken. The following data were analyzed: age at diagnosis, stage, race, histologic type, grade, depth of myometrial invasion, absence or presence of associated hyperplasia, and survival. The mean age of the patients was 64.8 years. Sixty (73%) of the 82 patients were considered estrogen-positive either because of obesity (body mass index > or = 27.3) or the use of unopposed exogenous estrogen. There were no statistically significant differences between estrogen-positive and estrogen-negative patients. Patients > or = 65 years had a 5-year survival of 60% compared with 74% for younger patients. There was a trend toward higher histologic grade among the older patients. Otherwise no statistically significant differences were found between these two groups. Estrogen-negative women > or = 65 years had the worst prognosis with a 5-year survival of 29%. As identified by other investigators, age at diagnosis is a significant indicator of prognosis in patients with endometrial carcinoma. In this series, thin, older (> or = 65 years) women who developed endometrial carcinoma had the worst prognosis.

Adenocarcinoma↗
PubMed1992

National working conference on smoking and body weight. Task Force 1: Mechanisms relevant to the relations between cigarette smoking and body weight.

Careful, comprehensive, and empirical observations provide the building blocks of the sciences, whereas theory and mechanisms provide the "cement" to hold the blocks together and serve as blueprints to direct future building. This article resulted from several days of discussion regarding theories that may underlie the relation between cigarette smoking and body weight and the relation between smoking cessation and body weight. The working group composed of social and biological scientists who addressed this assignment considered what is already known within the smoking and body weight literature and also considered relevant findings from studies of smoking or body weight regulation that have not directly addressed the interaction of these variables. As expected, we were successful at listing some of what is not known and what is worth knowing. We also tried to identify fruitful possibilities for research activity that might clarify mechanisms of action and eventually lead to theoretical development. Because we do not believe that the present state of our deliberations merits the label of theories, we decided, instead, to report the summary of these deliberations as potential mechanisms relevant to the relation between smoking and body weight.

Adult↗
PubMed1991

Endothelial cells transformed by SV40 T antigen cause Kaposi's sarcomalike tumors in nude mice.

Injection into nude mice of a well-differentiated SV40 T-antigen-transformed murine endothelial cell (EC) line results in widespread invasive tumors confined to connective tissues. The tumors, which do not metastasize, consist of both host-derived cells and transformed EC, displaying histologic features typical of Kaposi's sarcoma (KS). Although the EC is believed to be the cell of origin in KS, this has not been proven and is the subject of debate. The unusual tumorigenicity of this transformed cell suggests that EC-specific gene products induced by SV40 T antigen may contribute to tumorigenesis by autocrine growth stimulation and recruitment of host cells. KS-like tumors may be the result of EC alteration by any virus that induces relevant EC-derived cytokines.

Animals↗
PubMed1990

Symptomatic rubella re-infection in early pregnancy and subsequent delivery of an infected but minimally involved infant. A case report.

A case of serologically proven symptomatic rubella re-infection in early pregnancy in a healthy multigravida who had been successfully vaccinated is reported to illustrate that the risk to the fetus is considerably less than with primary infection. The infant was infected, as evidenced by specific IgM in cord blood, but had no stigmata of congenital rubella at birth. Growth retardation was apparent at 6 months and hearing loss, not necessarily due to rubella, was detected at 8 months. Rubella re-infection, which may now be distinguished serologically by the urea degradation test from primary rubella, need not necessarily be an indication for termination of pregnancy.

Adult↗
PubMed1990

Characterization of infectious transcripts from a potato virus X cDNA clone.

A full-length cDNA clone of potato virus X (PVX) has been constructed and fused to the bacteriophage T7 promoter in an in vitro transcription vector. Transcripts derived from this template (pMON 8660) were infectious when inoculated onto the local lesion host, Chenopodium amaranticolor. The infectivity of these transcripts was approximately 0.2% that of authentic PVX RNA. Lesions sampled from plants inoculated with these transcripts contained virus particles and virus aggregates typically observed in lesions from plants inoculated with authentic PVX RNA, as evidenced by electron microscopy. In addition, progeny virus isolated from these lesions was as infectious as progeny virus from an authentic PVX RNA infection when inoculated onto new local lesions plants. Infectious transcripts derived from PVX cDNA clones will facilitate analysis of the molecular aspects of PVX infection.

Antigens, Viral↗
PubMed1989

Molecular analysis of the inhibitory effect of phosphorylated ribavirin on the vesicular stomatitis virus in vitro polymerase reaction.

The effect of phosphorylated ribavirin on the vesicular stomatitis virus in vitro transcription reaction was examined. Analysis of the kinetics observed when the concentrations of nucleoside triphosphates were varied was performed with vesicular stomatitis virus wild-type standard virions. Double-reciprocal and Eadie-Hofstee plots showed competitive inhibition with all natural nucleoside triphosphates when both ribavirin diphosphate (RDP) and ribavirin triphosphate (RTP) were used. The Km values for ATP obtained for the wild-type polymerase were similar to those reported previously. To further characterize the observed inhibition kinetics, in vitro transcription products synthesized in the presence or absence of RDP and RTP were purified by CsCl centrifugation and were primer extended with oligonucleotides specific for either positive-sense leader or nucleocapsid mRNA transcripts. The ratios of leader to nucleocapsid mRNA were measured from primer-extended in vitro transcription products. It was found that the addition of RDP or RTP did not significantly change the in vitro ratio, suggesting that the polymerase is blocked before it enters the 3' end of the template.

Antiviral Agents↗
PubMed1988

Effect of phosphorylated ribavirin on vesicular stomatitis virus transcription.

The effect of phosphorylated ribavirin on a vesicular stomatitis virus (VSV) in vitro transcription reaction was examined. Viral mRNA synthesized in the presence of the 5' mono-, di-, and triphosphorylated forms of the drug translated with equal efficiencies under the test conditions. However, all three phosphorylated species inhibited VSV transcription. The mono- and diphosphorylated forms of the drug possessed approximately two to three times the inhibitory activity as the triphosphorylated form. Transcripts synthesized in the presence of drug were full length and were absent of incorporated drug. Inhibition by ribavirin 5'-diphosphate could be reversed by the addition of UTP, CTP, and GTP, while the addition of GDP to the reaction did not reverse inhibition. Ribavirin diphosphate was added to a La Crosse virus in vitro transcription assay to determine whether an inhibitory effect could be established in a viral system that was more sensitive to ribavirin than was VSV; it led to profound inhibition of RNA synthesis at concentrations as low as 0.1 microgram/ml. These data suggest that ribavirin has an effect on the initial steps of transcription by some RNA-dependent RNA polymerases and that this effect may be mediated by several phosphorylated forms.

Nucleotides↗