First Group Of Studies Research Articles

Sedation and Performance Issues in the Treatment of Allergic Conditions

This article evaluates and summarizes the results of studies investigating the central nervous system effects of second-generation antihistamines, with particular emphasis on psychomotor and cognitive effects. The data sources were computer-assisted MEDLINE searches using the search terms histamine H1 antagonists, psychomotor performance, sleep, and specific drug names, including astemizole, cetirizine, loratadine, and terfenadine; the searches were limited to studies in humans. Only controlled studies (placebo or active control or both) using standardized or quantitative methods for defining drug-induced effects on sedation, psychomotor performance, or cognition were reviewed. Additional published studies were identified within the references of the first group of studies. Finally, representative studies were selected for summarization. Objective and subjective measures of sedation show that loratadine and terfenadine produce sedation at a rate comparable with placebo. Moreover, these agents, when used at standard therapeutic doses, do not produce detrimental effects on objective measures of psychomotor or cognitive function. Cetirizine is associated with sedation or psychomotor impairment in some studies but not in others. The data on central nervous system effects of astemizole are limited and were not evaluated. The absence of sedation and psychomotor or cognitive impairment in patients receiving loratadine or terfenadine justifies the cost of these agents, particularly for patients who drive, pilot aircraft, or operate machinery. Whether the potential for rare but serious cardiovascular events (associated with astemizole and terfenadine) is justifiable must be decided on a case-by-case basis.

Role of the Environment in Falls Prevention

Environmental change offers an attractive approach to falls prevention, particularly as part of multidimensional intervention strategies. This article reviews and summarizes prior research that has examined environmental factors in falls experienced by older people in community and long-term care settings. Limitations of this research as a basis for falls prevention activities also are discussed. Studies that focused on environmental hazards as well as those that examined the interaction of environmental conditions and environmental use activities from a situational perspective are included. The first group of studies suggests an approach to falls prevention centered on hazard removal; the second group suggests an approach centered on the provision of more supportive environments that reduce excessive environmental demands. Environmental change and falls prevention in long-term care and community settings, including common barriers to change among older individuals living in the community, are discussed.

Testosterone is required for gonadotropin-releasing hormone stimulation of luteinizing hormone-beta messenger ribonucleic acid expression in female rats.

Pulsatile GnRH stimulates the synthesis and secretion of LH and FSH in both male and female rats. In the male rat, exogenous GnRH pulses increase alpha, LH and FSH beta messenger RNAs (mRNAs) 3-fold within 24 h. In contrast, the results of recent in vivo and in vitro studies have shown that GnRH stimulates an increase in alpha and FSH beta mRNAs, but not LHbeta. However, during the estrous cycle, LHbeta mRNA increases during the GnRH-induced LH surge on proestrus afternoon. This increase in LHbeta mRNA appears to be coincident with a transient rise in serum testosterone (T). Therefore, the present study was conducted to determine whether T has a role in facilitating GnRH stimulation of LHbeta mRNA expression. In the first group of studies, adult female rats were ovariectomized, and T implants were inserted sc 7 days before the study (serum T, 1.86 ng/ml). Animals received iv pulses of GnRH (25 ng; 30-min interval) for 6-24 h (saline pulses to controls). The data showed that in the presence of T, GnRH stimulated a significant increase in LHbeta (as well as alpha and FSH beta) mRNAs within 6 h (P < 0.05 vs. saline-pulsed controls). Other results revealed that T treatment was critical to the stimulatory effect of GnRH on LH beta mRNA. A second group of studies examined the time course and dose effects of T on LH beta mRNA expression. Maximal LH beta mRNA responses to GnRH (3-fold increase vs. saline controls; P < 0.05) were seen after pretreatment with the lowest dose of T examined (serum T, 0.42 ng/ml), which is similar to T concentrations on proestrus. Higher doses of T suppressed LH release, as well as LH mRNA responses to GnRH. The T-induced LHbeta mRNA response to pulsatile GnRH was seen within 24 h of exposure to T and was the result of an androgenic action, as similar results were observed in rats that received dihydrotestosterone. These findings suggest that T is required to facilitate GnRH stimulation of LHbeta mRNA in the female rat. Moreover, in the presence of the concentrations of T seen on proestrus, LHbeta mRNA increases within 6 h, which is similar to the time course seen during the LH surge. Thus, the present results also suggest that the combined effects of the rise in serum T and increased GnRH secretion induce the rapid rise in LHbeta mRNA expression on the afternoon of proestrus.

Visual estimation of ejection fraction by two-dimensional echocardiography: the learning curve.

Our purpose was to determine the learning curve of visual estimation of ejection fraction (EF) by echocardiography. Sixty consecutive patients, who had clinically indicated echocardiography and radionuclide ventriculography (RVG) within 1 month were selected. Five standard views were reviewed independently by a first-year cardiology fellow, a private cardiologist, and an experienced echocardiographer. Observers were given feedback of the RVG EFs immediately after estimating the EF on each study. To assess the effect of learning, the echocardiographic studies were divided into three groups of 20 and were read successively by each observer. A statistical comparison of the two methods was performed for each group. The correlation between the two techniques for the first group of studies was marginal. There was a significant improvement in the correlation with subsequent groups. The correlation did not change significantly with the last group of studies compared with the second group. In conclusion, visual estimation of EF by two-dimensional echocardiography can be learned, with a learning curve of approximately 20 studies if immediate feed-back is available.

Campaign Contributions and Legislative Voting: Milk Money and Dairy Price Supports

-M W fANY MEMBERS of the press and the public apparently believe that interest groups buy influence by contributing to political campaigns. This belief has been cited as reason for Congress either publicly to finance congressional campaigns or to place a limit on the amount of monies that a candidate may receive from political action committees. In spite of this public discussion, few scholars have investigated systematically whether campaign contributions directly affect public policy or, more specifically, whether the likelihood that a legislator will vote for a bill favored by an interest group increases upon receiving a contribution from the group. Empirical research on legislative voting can be categorized into two groups. The first group of studies has investigated the relationship between dimensions of voting (e.g. composites of votes on several issues) and measures of general district opinion such as referendum results (Miller and Stokes, 1963; Erickson, 1978; Kuklinski, 1977, 1978; Kuklinski and McCrone, 1980; and Markus, 1974). The second group has focused on the relationship between a congressman's vote on specific bills and the opinions (or self-interest) of sections of his constituency (Bernstein and Anthony, 1974; Danielson and Rubin, 1977; Kau and Rubin, 1978, 1979; and Abrams, 1977). Opinion is usually measured by socioeconomic characteristics. To elaborate on Kuklinski's (1979) criticism, the presumption is that legislative voting is influenced by constituents' opinions but socioeconomic characteristics are no more than proxy variables for such opinions. Most of those used are poor proxies because a priori it is not clear which of many characteristics will predict voting and because the ability of a characteristic to predict voting presumably varies over issues. To be an adequate proxy, a socioeconomic characteristic must be sufficiently refined so that it is related to opinion on a specific bill. In the case of a vote on a specific piece of legislation, the size of a group for whom the issue is salient may be a convincing measure of its influence; and the more precisely the group is defined, the better the variable as a proxy. For instance, in this study dairy industry characteristics arguably are better measures of opinion on dairy price supports than general district characteristics such as percentage of the population which is rural. Furthermore, dairy industry characteristics presumably are poor measures of the relevant dimensions of district opinion on issues such as civil rights. For issues involving specific subgroups of votes, the relationship between a proxy variable and voting is not necessarily a black box. However, district level measures of

Cell elastimetry in the detection of antineutrophil antibodies

Cell elastimetry has been applied to the measurement of antineutrophil antibodies. This technique measures, under direct visualization, the negative pressure required of aspirate PMNs into small-pored pipettes. Two groups of studies were carried out: (A) In the first group of studies, normal PMNs were incubated with 1 of 8 known antineutrophil serums. Each serum significantly decreased membrane deformability-- i.e., cells became more rigid. The study was conducted in an entirely blind fashion. Randomly coded serums from patients and controls were studied for deformability by observers unaware of the code. (B) In the second group of studies, sera containing immune complexes were incubated with normal PMNs. No significant effects were noted upon deformability. As a single cell assay that partially reflects membrane rigidity, elastimetry may, therefore, have potential in the further characterization of mechanisms by which such antineutrophil antibodies compromise neutrophil functions.

Cell Elastimetry in the Detection of Antineutrophil Antibodies

Cell elastimetry has been applied to the measurement of antineutrophil antibodies. This technique measures, under direct visualization, the negative pressure required to aspirate PMNs into small-pored pipettes. Two groups of studies were carried out: (A) In the first group of studies, normal PMNs were incubated with 1 of 8 known antineutrophil serums. Each serum significantly decreased membrane deformability—i.e., cells became more rigid. The study was conducted in an entirely blind fashion. Randomly coded serums from patients and controls were studied for deformability by observers unaware of the code. (B) In the second group of studies, sera containing immune complexes were incubated with normal PMNs. No significant effects were noted upon deformability. As a single cell assay that partially reflects membrane rigidity, elastimetry may, therefore, have potential in the further characterization of mechanisms by which such antineutrophil antibodies compromise neutrophil functions.

Review of research on reversal errors.

This review focuses on the phenomenon of reversals: the tendency for children, especially those with reading difficulties, to make errors of orientation ("b-d") or sequencing ("was-saw"). After a brief historical (Orton) and theoretical (Gibson) look at the phenomenon, a variety of studies on reversals is reviewed and evaluated. The first group of studies reviewed and discussed involves neurological and psychological factors associated with reversals, e.g., age, training. The second set of investigations summarizes the literature relating reversals to reading disabilities and to future reading achievement.

Monosynaptic activation of a direct reticulo-spinal pathway by the dentate nucleus.

Experiments were performed to test the hypothesis that the output of the dentate nucleus can affect the excitability of spinal neurons via the reticular formation. In the first group of studies, the response of neurons in the medial reticular formation to stimulation of the dentate nucleus was investigated. In the second set of experiments, stimuli were applied in the same region of the medial reticular formation in order to determine whether neurons in the dentate nucleus could be antidromically activated from this part of the brainstem. The results indicate that the output from the dentate nucleus monosynaptically activates medial reticular neurons which project to the spinal cord. This finding, together with the observation that stimulation of the medial reticular formation can antidromically activate neurons in the dentate nucleus, demonstrates that there is an anatomical substrate by which the dentate nucleus can affect the excitability of spinal neurons via a rapidly conducting reticulospinal pathway.

A phylogenetic perspective for social behavior in primates.

Three selected groups of studies of primate social behavior and development are discussed. In the first group of studies the social development of rhesus monkeys reared in different environments is considered. Rhesus show remarkable similarity in behavior in diverse environments, demonstrating a phylogenetic set to develop species-typical behavioral repertoires. The second set of studies reports on three species (Macaca mulatta, Macaca fasicularis, and Erythrocebus patas) reared in similar settings. Species differences observed in these settings were a result of phylogenetic set. Finally, mother-infant seperation studies conducted with several monkey species are reviewed. The results of these studies were interpreted to be the product of each species, the specific setting or apparatus used, and the independent variable manipulation employed. Caution is recommended in cross-species generalization within primates.

Programed Instruction in Science and Mathematics

IN THIS chapter, research in programed instruction in the areas of science and mathematics is reviewed primarily for the period from October 1, 1960, to October 1, 1963, although there is one article that appeared as late as December 1963. No general review of the history and nature of programed instruction is presented; general familiarity with programed instruction on the part of the reader is necessarily assumed. The reader who is not acquainted with programed learning and teaching machines should consult a basic text, such as the volume edited by Lumsdaine and Glaser (1960). In Programs, '63 (Hanson, 1963), 69 programs in the natural sciences and 123 programs in mathematics are listed. This compilation represents about 55 percent of the total number of programs developed in all subject matter areas. Although some aspects of almost any academic subject can be programed, science and mathematics are numerical leaders of the field. To a great extent, this frequent use of programed instruction in science and mathematics is reflected in the amount of research in these disciplines. It is not a purpose of this chapter to survey developments in the curriculum of science and mathematics. However, in some of the experiments in programed instruction to be reported, investigators employed programs based on the new developments in curriculum; in other experiments, conventional materials were used. Purely theoretical or expository papers concerning programed instruction are excluded from this chapter. Coverage of the experimental literature is divided into two major sections: (a) presentation of results of what may be termed methods studies, in which the practical effectiveness of programed instruction is compared with that of conventional methods of teaching, and (b) the description of findings in experimental studies in which some of the issues in the theory and technique of effective programing have been explored. In this chapter, the contributions of the latter group are termed analytical studies. As one might expect, some investigations to be reviewed touch both upon methods and upon analyses. The first group of studies is generally concerned with the practical value of programed instruction as a classroom procedure and with the role of the teacher in such procedures; the second group of investigations pertains to experimental attempts to identify factors that make programed instruction effective and workable. For the latter group of investigations, special emphasis is placed upon improvement of programing theory and techniques.