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Biomedical subjects

L R Martin

Publications and source records attributed to L R Martin.

At least 19 recordsLinked to original sources
PubMed2001

Recombinant measles viruses expressing heterologous antigens of mumps and simian immunodeficiency viruses.

We have genetically engineered a panel of recombinant measles viruses (rMVs) that express from various positions within the MV genome either the HN or F surface glycoproteins of mumps virus (MuV) or the env, gag or pol proteins from simian immunodeficiency virus (SIV). All rMVs were rescued from the respective antigenomic plasmid constructs; progeny viruses replicated comparably to the progenitor Edmonston B MV, but showed slight propagation retardation, which was dependent on the size and nature of the expressed proteins and on the genomic position of the inserts. All transgenes except that encoding mumps F glycoprotein were faithfully maintained and expressed even after virus amplification by 10(20). Our results suggest possible applications of rMVs as live-attenuated, multivalent vaccines against retroviruses such as SIV and HIV as well as other pathogens more distantly related to MV than MuV.

Animals↗
PubMed2001

Effective planning and implementation of ecological rehabilitation projects: a case study of the regional municipality of Waterloo (Ontario, Canada).

The literature guides environmental planning and, specifically, how to use ecological rehabilitation projects to achieve long-term planning goals and landscape-scale environmental sustainability. There is, however, a perceived gap between principles in the literature and the use of them by practitioners involved in smaller-scale ecological rehabilitation projects. Using interviews with practitioners involved in 11 projects within the Regional Municipality of Waterloo, Ontario, Canada, we tested whether practitioners used five principles for effective planning and implementation of ecological rehabilitation that we derived from the literature. These five principles were: establishing political and ecological context, using ecologically appropriate objectives and practices, using comparative multidisciplinary and cross-scale approaches, using adaptive planning and implementation, and establishing good communication within and external to projects. Few projects followed all five principles, and practitioners indicated that they used three more project-specific principles: obtaining political/social support, promoting projects and changing attitudes about projects, and securing sufficient and persistent funding to maintain a project's life. While the literature emphasizes that ecological rehabilitation is only effective if projects are coordinated on a watershed basis, most practitioners focused solely on the goals of their specific project. The gap between literature and practice may arise because most practitioners are new to the field of ecological rehabilitation and still are focused on the methods involved. Time pressures force practitioners to obviate the literature and get projects started quickly, lest support evaporate. Complicating these difficulties is decreased support from federal and provincial governments for large-scale environmental planning. It is unclear whether ecological rehabilitation projects in Waterloo Region (at least) will ever become effective at promoting landscape-scale ecological goals or remain smaller-scale stop-gaps.

Animals↗
PubMed2001

Facilitation of patient involvement in care: development and validation of a scale.

The authors describe the development and validation of the Facilitation of Patient Involvement Scale, a 9-item measure of the degree to which patients perceive that their physicians actively facilitate or encourage them to be involved in their own healthcare. They first assessed the unidimensionality of the measure, conducting factor analysis in a pilot study of 236 individuals. Subsequently, they assessed the scale's reliability and validity with additional samples of 333, 338, 44, and 84 participants. Reliability of the scale was very high, with average Cronbach's alpha levels of .91. To test the validity of the scale, they used correlational and multiple regression analyses. The findings indicated that patients' satisfaction with their medical encounters was associated with patients' perceptions of facilitation; that perceptions of facilitation were also moderately correlated with general adherence patterns and preferred communication styles; and that patient age, gender, and education level were not relevant to perceptions that healthcare professionals promote patients' involvement in their own care.

Adult↗
PubMed2000

Comparing personality scales across time: an illustrative study of validity and consistency in life-span archival data.

The goals of this study were: (a) to examine whether personality scales, meaningful in contemporary terms, could be derived from archival data; and (b) to use these scales to aid our understanding of the relation of personality to mortality. NEO PI-R data and a battery of archival items, taken from Terman's Life Cycle Study, were collected on two new samples (sample 1 mean age = 11.9, n = 167; sample 2 mean age = 22.2, n = 203). Measurement invariance of the archival scales was assessed, and validity was examined using both rational analyses and associations with the Five Factor Model. It was demonstrated that interpretable scales can be derived from 50- to 70-year-old archival data. The archival adult personality data were then used to predict mortality. Conscientiousness remains the strongest personality predictor of longevity. Criteria for establishing the validity of archivally derived scales are suggested.

Adolescent↗
PubMed2000

Mengovirus and encephalomyocarditis virus poly(C) tract lengths can affect virus growth in murine cell culture.

Many virulent aphthoviruses and cardioviruses have long homopolymeric poly(C) tracts in the 5' untranslated regions of their RNA genomes. A panel of genetically engineered mengo-type cardioviruses has been described which contain a variety of different poly(C) tract lengths. Studies of these viruses have shown the poly(C) tract to be dispensable for growth in HeLa cells, although the relative murine virulence of the viruses correlates directly and positively with tract length. Compared with wild-type mengovirus strain M, mutants with shortened poly(C) tracts grow poorly in mice and protectively immunize rather than kill recipient animals. In the present study, several murine cell populations were tested to determine whether, unlike HeLa cells, they allowed a differential amplification of viruses with long or short poly(C) tracts. Replication and cytopathic studies with four hematopoietically derived cell lines (CH2B, RAW 264.7, A20.J, and P815) and two murine fibroblast cell lines [L929 and L(Y)] demonstrated that several of these cell types indeed allowed differential virus replication as a function of viral poly(C) tract length. Among the most discerning of these cells, RAW 264.7 macrophages supported vigorous lytic growth of a long-tract virus, vMwt (C(44)UC(10)), but supported only substantially diminished and virtually nonlytic growth of vMC(24) (C(13)UC(10)) and vMC(0) short-tract viruses. The viral growth differences evident in all cell lines were apparent early and continuously during every cycle of virus amplification. The data suggest that poly(C) tract-dependent attenuation of mengovirus may be due in part to a viral replication defect manifest in similar hematopoietic-type cells shortly after murine infection. The characterized cultures should provide excellent tools for molecular study of poly(C) tract-mediated virulence.

Animals↗
PubMed1998

Transfer of preventive health programs to physicians' practices through medical organizations.

BACKGROUND: Transferring new information to practicing physicians is a complex and often faulty process. Effective transfer is a challenging goal that requires a strategy for reaching large numbers of physicians throughout the country in a short time. However, methods for disseminating preventive health techniques such as smoking cessation have not been well organized. Smoking is the single most important preventable cause of premature mortality, so dissemination of research-based smoking-cessation techniques to physicians' practices is a priority for the National Cancer Institute (NCI). METHODS: NCI recruited national, professional medical organizations to collaborate in disseminating smoking-cessation techniques. The goal was to co-sponsor 50 Train-the-Trainer (TT) seminars that would prepare 2,000 professionals as volunteers to instruct their colleagues in smoking-cessation techniques. NCI provided all materials, faculty (nine professionals), advance logistics, CME credits, and follow-up. The co-sponsor organizations helped develop the training plan, promoted training among their members, enrolled professionals to be trained, and made logistical arrangements for the training sites. RESULTS: During the 4 years of the program, NCI recruited 11 national organizations as co-sponsors; conducted 53 TT seminars in 22 states and Washington, DC; and trained 2,098 professionals as smoking-cessation trainers, who practice nationwide. The many lessons learned provide the basis for recommendations that can assist others who want to work with professional organizations. CONCLUSION: The National Cancer Institute demonstrated that national organizations of medical professionals can help to disseminate effectively a research-based smoking-cessation program. Twelve recommendations are presented to help others disseminate preventive health techniques nationwide.

Education, Medical, Continuing↗
PubMed1997

Parental divorce: effects on individual behavior and longevity.

Using an archival prospective design, the authors studied associations among parental divorce occurring during participants' childhood, adult psychosocial mediators, and mortality over the life span of a subgroup of participants (N = 1,261) in the Terman Life Cycle Study (1921-1991). Children from divorced families grew up to show a higher risk of premature mortality across the life span. The higher mortality risk for men was explained, in part, when 3 mediating factors were controlled: Men who had experienced parental divorce were more likely to have their own marriages end in divorce, obtained less education, and engaged in fewer service activities. Women who had experienced parental divorce smoked more and were more likely themselves to divorce, both of which predicted higher mortality risk. The findings extend previous work on the negative sequelae of parental divorce to long-term effects on personality and longevity.

Adolescent↗
PubMed1996

The immunogenic and pathogenic potential of short poly(C) tract Mengo viruses.

We have shown previously that genetically engineered Mengo viruses with artificial deletions in their 5' noncoding polyribocytidylic acid (poly(C)) tracts are highly attenuated for the natural murine host and also for other animals such as baboons, macaques, and domestic pigs. The present report further characterizes select short poly(C) tract Mengo viruses in the natural murine host. A positive correlation was found between the length of the poly(C) tract and murine virulence, as measured by virus brain titers and brain lesion scores after infection. Histological examination of brain tissue collected from infected animals clearly showed that the short poly(C) tract viruses did not induce the devastating pathological effects characteristic of animals inoculated with wild-type virus. Instead, the short-tract Mengo viruses proved excellent immunological agents. A dose of only 100 plaque-forming units of vMC24 (poly(C) tract: C13UC10), injected subcutaneously, protected 80% of recipient animals against a normally lethal dose of encephalomyocarditis virus. The protection was long-lived, and animals similarly immunized with vMCo virus (poly(C) tract: Co) still had protective neutralizing antibody titers up to 16 months after inoculation. In addition, the short-tract viruses proved genetically stable, in that the vMC24 virus did not yield detectable pathogenic revertants even after multiple, forced passages in 4-week-old mice. These studies suggest that Mengo viruses containing deletions in their poly(C) tracts are biologically safe and potent immunogens and imply that they may have uses as cardiovirus vaccines.

Animals↗
PubMed1996

Tandem mengovirus 5' pseudoknots are linked to viral RNA synthesis, not poly(C)-mediated virulence.

The RNA genomes from the cardioviruses, hepatoviruses, and aphthoviruses encode two to five tandem pseudoknots within their 5' untranslated regions. These pseudoknots lie adjacent to a pyrimidine-rich sequence, which in cardio- and aphthoviruses takes the form of a homopolymeric poly(C) tract. Seven deletion mutations within mengovirus pseudoknots PK(B) and PK(C) were created and characterized. tested in tissue culture, mengovirus genomes with alterations in PK(C) were viable but had small plaque phenotypes. Larger plaque revertants were isolated and partially characterized, and each proved to be a second-site pseudorevertant with (unmapped) changes elsewhere in the genome. The infectious PK(C) mutant viruses were highly lethal to mice, and deletions in this motif did not affect mengovirus virulence in the same manner as deletions in the adjacent poly(C) tract. In contrast, deletions in PK(B), or deletions which spanned PK(B) + PK(C), produced nonviable genomes. Cell-free translations directed by any of the altered PK sequences gave normal polyprotein amounts relative to wild-type mengovirus. But viral RNA accumulation during HeLa cell infection was dramatically impaired, even with the least disruptive of the PK(C) changes, suggesting the pseudoknots play an essential though undefined role in RNA synthesis and moreover that an intact PK(B) structure is critical to this function.

Animals↗
PubMed1996

Mutational analysis of the mengovirus poly(C) tract and surrounding heteropolymeric sequences.

Previously, we described three mengovirus mutants derived from cDNA plasmids, containing shortened poly(C) tracts (C8, C12, and C13UC10), that exhibited strong attenuation for virulence in mice yet grew like wild-type virus in HeLa cells. Thirteen additional mutants hav now been constructed and characterized. Five of these differ only in poly(C) length, including one with a precise deletion of the tract. The other mutants bear deletions into the regions juxtaposing poly(C). Studies with HeLa cells confirm the essential dispensability of mengovirus's poly(C) tract but reveal a subtle, measurable correlation between poly(C) length and plaque diameter. Virulence studies with mice also revealed a strong correlation between poly(C) length and virulence. For the poly(C)-flanking mutations, the 15 bases directly 5' of the tract proved dispensable for virus viability, whereas the 20 to 30 bases 3' of poly(C) were critical for growth, thus implicating this region in the basal replication of the virus.

Animals↗
PubMed1996

Parish nursing: keeping body and soul together.

"So what exactly is parish nursing?" I eagerly asked Ann Solari-Twadell when she introduced herself in our nurses networking group at the National Wellness Conference in Wisconsin. The Director of the National Parish Nurse Resource Center in Illinois, Ann described a unique, innovative role of promoting health, healing and wholeness of individuals, families and churches.

Canada↗
PubMed1995

Psychosocial and behavioral predictors of longevity. The aging and death of the "termites".

Impulsive, undercontrolled personalities and major family stresses are known predictors of impaired adjustment, but long-term health effects are unclear. In an archival prospective cohort design, we followed up on L. M. Terman's (Terman & Oden, 1947) sample of gifted children by collecting and coding death certificates for the half of the sample that is now dead. Statistical survival analyses were used to predict longevity and cause of death as a function of parental divorce during childhood, unstable marriage patterns in adulthood, childhood personality, adult adjustment, and possible mediating health behaviors. Psychosocial factors emerged as important risks for premature mortality.

Adolescent↗
PubMed1995

Childhood conscientiousness and longevity: health behaviors and cause of death.

Previous research showed that conscientiousness (social dependability) in childhood predicted longevity in an archival prospective cohort study of bright children first studied by Terman in the 1920s (H. S. Friedman et al., 1993). Possible behavioral mechanisms for this robust association are now examined by gathering cause of death information and by considering the possible mediating influences of drinking alcohol, smoking, and overeating. Survival analyses (N = 1,215) suggest that the protective effect of conscientiousness is not primarily due to accident avoidance and cannot be mostly explained by abstinence from unhealthy substance intake. Conscientiousness may have more wide-ranging effects on health-relevant activities.

Adolescent↗
PubMed1995

An archival prospective study of mental health and longevity.

The relationship between mental health status and longevity was examined in an archival prospective cohort study (N = 1,103) derived from work begun by Lewis Terman in the 1920s. Degree of psychological maladjustment, cumulatively rated by Terman and his colleagues as of 1950, was found to be related to higher risk of all-cause mortality over a 4-decade follow-up period. The differences among causes of death were nonsignificant, but there was some indication that mental health problems were more strongly related to deaths from injury and cardiovascular disease. The overall relationship was significant for men but weaker for women. The effect was not substantially mediated by alcohol consumption, obesity, or cigarette smoking.

Adolescent↗
PubMed1995

Playing with pets and longevity among older people.

Models of the relations between contact with pets and better health are examined in an archival prospective study using data derived from the longitudinal study initiated by Terman in 1921 (current N = 343 men, 300 women). In survival analyses of documented longevity, playing with pets in 1977 (M age = 67 years) was not associated with mortality risk through 1991 for the total sample nor for those who were unmarried or those who were less satisfied with their human relationships. Playing with pets was not associated with health-prone attributes or healthy behaviors such as personality, social ties, education, and smoking.

Aged↗
PubMed1990

Partition of parinaroylphosphatidylethanolamines and parinaroylphosphatidylglycerols in immiscible phospholipid mixtures.

Partitioning of two parinaroyl phosphatidylethanolamines and two parinaroyl phosphatidylglycerols between solid and fluid phase phospholipids was examined. Fluorescence quantum yields and fluorescence polarization measurements were used to calculate Ks/fp, the solid to fluid partition coefficient of each probe (Sklar, L.A., Miljanich, G.P. and Dratz, E.A. (1979) Biochemistry 18, 1707-1716). In the immiscible mixture dipalmitoylphosphatidylcholine and dilinoleylphosphatidylcholine, both 1-palmitoyl-2-trans-parinaroylphosphatidylethanolamine and 1-palmitoyl-2-transparinaroylphosphatidylglycerol partitioned preferentially into solid phase lipid with mean Ks/fp values (calculated from quantum yields) of 3.4 +/- 1.5 and 2.1 +/- 0.7, respectively. In contrast, 1-oleoyl-2-cis-parinaroylphosphatidylethanolamine and 1-oleoyl-2-cis-parinaroylphosphatidylglycerol partitioned preferentially into fluid phase lipid in the same model system with mean Ks/fp values (calculated from quantum yields) of 0.44 +/- 0.26 and 0.16 +/- 0.07, respectively. Fluorescence polarization data on the same four parinaroyl phospholipids in mixtures of solid-phase dimyristoylphosphatidyl ethanolamine and fluid-phase dilinoleoylphosphatidylglycerol were similar to those obtained in the immiscible phosphatidylcholine system, demonstrating that the partitioning of these probes is not strongly dependent on head group. Knowledge of the partition properties of these fluorescent probes is relevant to use of these probes in investigation of the phase behavior of Escherichia coli inner membrane lipids, since phosphatidylethanolamine and phosphatidylglycerol species account for approximately 95% of these lipids.

1,2-Dipalmitoylphosphatidylcholine↗