Investigation of palpitations

The uncomfortable awareness of a beating heart--palpitations--is a common complaint that can occur under normal or abnormal circumstances. For example, normal palpitations occur with exercise, emotions, and stress, or after taking substances that increase adrenergic tone or diminish vagal activity (coffee, nicotine, and adrenergic or anticholinergic drugs). Normal palpitations are recognised as such because individuals who experience them realise or are told that something happened to accelerate the normal rhythm of the heart. However, some people find sinus tachycardia troublesome enough to seek medical attention. In other situations palpitations are clearly abnormal. The heart beat which is felt for no apparent reason, may be fast, or strong and slow, or feel like a missed or extra beat. Although these abnormal palpitations usually point to a cardiac arrhythmia, this is not always the case. Moreover, many patients with arrhythmias do not have palpitations but manifestations such as syncope, shock, and chest pain (sudden death is also possible). We will discuss the approach to the patient who seeks medical attention because of a history of palpitations, with special emphasis on the history, physical examination, and 12-lead electrocardiogram (ECG) because they are simple and inexpensive diagnostic tools that are available to most physicians.     

Rational versus intuitive problem solving: How thinking “off the beaten path” can stimulate creativity.

We compared the effects of rational versus intuitive problem solving on creativity. We argued that the relative effectiveness of these approaches depends upon an individual's typical thinking style such that individuals will be more creative when they adopt a problem-solving approach that differs from their typical style of thinking (e.g., individuals who avoid rational thinking will exhibit higher creativity when they are instructed to rely on rational problem solving). We tested this hypothesis in a sample of undergraduate students generating creative ideas in response to a real-world problem. In support of our hypothesis, we found that problem-solving approach and individual differences in thinking style interact such that creativity is highest when individuals use a nontypical problem-solving approach. (PsycINFO Database Record (c) 2011 APA, all rights reserved)     

Optimal stimulation: A model of disordered activity and performance in normal and deviant children.

There is considerable evidence that organisms can moderate incoming sensory stimulation to more closely approach optimal levels of arousal. When normal individuals are exposed to unusually high or low sensory input, they tend to show "disordered" behavior similar to that of certain chronically disordered populations, for example, hyperactive and autistic children. The present authors propose that at least some of the deviant behavior displayed by such disordered children represents a functional set of homeostatic responses to conditions of abnormal sensory input. Attempts to correct chronic imbalances in arousal through antecedent manipulations of chemical and sensory stimulation have been relatively successful and may provide appropriate treatment as well as a better understanding of the mechanisms underlying many kinds of disordered behavior. (5 p ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

The role of the anterior commissure in callosal agenesis.

Two individuals with callosal agenesis (J.P. and M.M.) and 10 neurologically normal participants were tested on tasks requiring interhemispheric visual integration. M.M., whose anterior commissure was within normal limits, was much worse at matching colors and letters between visual fields than within visual fields, whereas J.P., whose anterior commissure was greatly enlarged, showed no evidence of interhemispheric disconnection. This suggests that in some cases of callosal agenesis, probably a minority, an enlarged anterior commissure may compensate for the lack of the corpus callosum. Neither acallosal participant showed interhemispheric disconnection on tasks requiring integration of location and orientation, however, suggesting that the anterior commissure plays no role in such tasks. These tasks may depend on subcortical commissures, such as the intertectal commissure. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Treatment of asymptomatic diabetes mellitus

A large number of individuals currently diagnosed as having diabetes mellitus are asymptomatic. In order to provide rational therapy for this patient population, it is necessary to focus upon the differences between these patients and the classic prototypes with polyuria and weight loss, who require insulin for survival. Patients with asymptomatic diabetes do not need insulin for survival, and, by definition, they do not need it to alleviate symptoms. They tend to be middle-aged and overweight, but they can be young and thin. Their degree of hyperglycemia is moderate, often indistinguishable from that of normal individuals in their day-to-day existence. Indeed, they can often be differentiated from normal persons only on the basis of their blood glucose response to the stress of a large dextrose challenge; in this regard, the potential problem of over-diagnosing diabetes has been discussed. Since the major problem facing patients with asymptomatic diabetes is accelerated atherogenesis, the therapeutic approach must be based upon efforts to delay or prevent the onset of vascular disease. It has yet to be shown that any therapeutic intervention helps such patients, but an argument has been made in support of the following goals in subjects with asymptomatic diabetes whose fasting blood glucose level is less than 170 mg/100 ml: (1) stop smoking, (2) control hypertension, (3) attain ideal body weight, and (4) maintain blood triglyceride and cholesterol levels well within normal limits. Attempts to lower blood glucose with either insulin or oral agents do not seem indicated in the majority of patients within this defined diabetic population.     

A comprehensive linkage analysis of chromosome 21q22 supports prior evidence for a putative bipolar affective disorder locus

Previously, we demonstrated evidence of linkage to bipolar affective disorder (BP) in a single large, multigenerational family with a LOD score of 3.41 at the PFKL locus on chromosome 21q22.3. Additional families showed little support for linkage to PFKL under homogeneity or heterogeneity, in that study. We have expanded on that analysis, with 31 microsatellite markers at an average marker spacing of 相似文献   

Associations of types of lens opacities between and within eyes of individuals: an application of second-order generalized estimating equations. The Framingham Eye Studies Group

The lens opacity characteristics of individuals constitute multivariate data. Our goal was to estimate the associations between the three main types of age-related lens opacities (nuclear, cortical, posterior subcapsular) both between and within eyes of individuals using cross-sectional data from the Framingham (Massachusetts) Eye Studies. We describe use of a recently proposed extension of the generalized estimating equations approach to marginal logistic models (GEE2), and we demonstrate that a variety of research problems can be investigated with this methodology. For example, in our data, there were strong associations of the same opacity types between the two eyes of individuals and weak associations between different types of opacities. We also note that estimation of such associations may be limited in other epidemiologic settings.     

Long-term phonatory instability in individuals with multiple sclerosis

This paper uses a new approach to describe and quantify the long-term phonatory instability of speakers with MS. Sustained vowel phonations of 20 individuals with a definite diagnosis of multiple sclerosis (MS) and 20 age- and gender-matched individuals with normal speech were recorded. The phonations were f0 and intensity analyzed and subjected to spectral analysis using the Fast Fourier Transform. Three methods for analyzing the instabilities are presented, compared, and related to perceptual judgments: (a) coefficients of variation, (b) magnitude-based analysis of spectral energy, and (c) frequency-based analysis of spectral components. All measures reliably distinguished between individuals with MS and persons with normal speech. A single factor based on a linear discriminant analysis of the frequency-based measures was especially useful in distinguishing these groups. Critical frequency bands of instability, corresponding to wow (1-2 Hz), tremor (around 8 Hz), and flutter (17-18 Hz), distinguished the MS group from those of the control group.     

Spectral analysis of intercycle heart fluctuations in the diethyl-ether-anaesthetized or pithed rat treated with l-hyoscyamine

An unstable variant of human butyrylcholinesterase (BChE) is described in four apparently unrelated individuals sensitive to succinylcholine. Sequencing of genomic DNA revealed a single nucleotide substitution which results in the replacement of amino acid residue Gly115 by Asp. This variant can be recognized by its increased instability under extremes of temperature such as heating and also freezing and thawing, both in homozygous and heterozygous states. When in heterozygous combination with the Atypical variant, it produces dibucaine and fluoride numbers which are intermediary between those of Atypical homozygotes and heterozygotes. After repeated freezing and thawing, however, these values approach those of homozygous Atypical plasma. Measurement of activity and immunoreactive BChE protein in plasma of individuals representing different combinations of this allele indicated that the presence of the Usual or Atypical enzymes seems to partially protect this variant from denaturation in vivo. Phenotyping fresh serum or plasma samples, before they are frozen, is critical for the identification of this, and possibly some other, unstable variants.     

Dynamic nuclear polarization at very low magnetic fields

Non-mosaic Klinefelter patients are generally azoospermic due to primary testicular failure. Nevertheless, in some cases, testicular spermatozoa may be recovered and utilized to fertilize oocytes via intracytoplasmic sperm injection (ICSI). As the risk for an increased number of gonosomes in these spermatozoa is unclear, preimplantation genetic diagnosis (PGD) may be attempted in the resulting embryos. In the present study, we report our experience with the combined approach of sperm retrieval by testicular fine needle aspiration (FNA), ICSI and PGD in seven consecutive non-mosaic Klinefelter individuals. In four patients, between one and five spermatozoa were retrieved in five out of nine consecutive attempts. In a fifth patient, only 10 round spermatids could be isolated. Mature spermatozoa were injected into a total of 16 metaphase-II oocytes, of which 11 (69%) remained intact. Two distinct pronuclei (2PN) were observed in four oocytes (36%) while a single pronucleus (1PN) was documented in two oocytes. Five cleavage stage embryos developed from the oocytes of two couples. Upon the request of one couple, their three embryos (two derived from 1PN oocytes) were transferred without PGD but pregnancy was not achieved. PGD by fluorescence in-situ hybridization (FISH) was performed in the two embryos of the other couple which were derived from normal fertilization. PGD results of one embryo were 18,18,X,X,Y, the embryo was not transferred and FISH analysis of the remaining blastomeres identified variable chromosome numbers in the nuclei. The second embryo was diagnosed as normal and was transferred, resulting in a successful pregnancy and birth. In conclusion, the results of this report indicate that a pregnancy and birth may be attained in azoospermic non-mosaic Klinefelter individuals by testicular FNA combined with ICSI. Due to the unknown risk of gonosomes aneuploidy in embryos from Klinefelter patients, PGD or prenatal diagnosis should be recommended.     

CoMFA analysis of biodegradability

We here examined the shear stress-induced platelet aggregation (SIPA) in various types of von Willebrand Disease (vWD), using a novel cone-and-plate viscometer recently developed by Ikeda et al. [1]. Under experimental conditions of high shear stress (90-108 dyne/cm2) known to induce von Willebrand factor (vWF)-dependent platelet aggregation in normal individuals, a variety of SIPA patterns, from a normal to total defect, were observed in 6 patients with type I vWD, while SIPA was totally absent in all 7 type IIA patients examined. One patient with Normandy type vWD exhibited a normal SIPA pattern under these experimental conditions. These findings, together with the vWF parameters of each patient, suggested that the presence of higher molecular weight multimers of plasma vWF, as well as an appropriate level of vWF antigen, is essential for SIPA to occur under high shear stress. Interestingly, vWF-dependent SIPA in 3 patients with type IIB vWD was found to be initiated by a low shear stress force, which did not induce such platelet aggregation in normal individuals. This might explain the intravessel platelet clumping that occurs, resulting in the intermittent thrombocytopenia observed in this type of the disease.     

Review of Becoming solution-focused in brief therapy.

Reviews the book, Becoming solution-focused in brief therapy by John L. Walter and Jane E. Peller (see record 1992-97355-000). With this book, the authors' goal was to produce a manual to aid therapists in learning the model of constructing solutions in brief therapy. Theoretical assumptions about personality development and psychotherapy technique which are crucial to implementing the model are presented. Walters and Peller work within a framework which assumes that problems are maintained by individuals functioning in family and organizational systems and that these individuals have the resources to change personal behavior. Interactional patterns between individuals in various systems are the focus of attention. The book is a clear and consistent portrayal of a therapy approach which is growing in application. It is readable and practical. In summary, this is an effective book which demonstrates alternate theories (exceptions) which could provide an almost miraculous solution to some troubled clients. Advanced graduate students and active practitioners will find this a helpful book in learning the model of constructing solutions. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Absence of ATM truncations in patients with severe acute radiation reactions

PURPOSE: Severe acute toxicity limits the effective use of radiotherapy in patients who are radiosensitive, and it is not usually possible to identify these radiohypersensitive (R-H) individuals before treatment commences. Five such R-H patients were detected over a 3-year period. We undertook this study to determine whether the severe acute radiohypersensitivity of these five individuals showed any correlation with cellular and molecular parameters known to be abnormal in radiosensitivity-related syndromes such as ataxia-telangiectasia (A-T). METHODS AND MATERIALS: Lymphoblastoid cells were isolated from fresh blood from the 5 R-H individuals who had previously demonstrated clinical R-H at least 9 months prior to sampling. Lymphoblastoid cell lines (LCLs) were established to determine the extent of postradiation chromosomal aberrations, cell cycle delay, cell proliferation, and tumor suppressor p53 protein stabilization. The polymerase chain reaction (PCR) and protein truncation (PTT) assays were used to test for the possibility of mutations in the gene mutated in A-T, termed ATM. RESULTS: LCLs derived from R-H subjects retained a significantly higher degree of radiation-induced chromosomal aberrations when compared to normal control LCLs. p53 stabilization by ionizing radiation appeared normal in all but one R-H subject. There was no evidence of A-T gene truncation mutations in any of the R-H subjects tested. CONCLUSIONS: All R-H subjects in this study had their cellular radiosensitivity confirmed by the chromosomal aberration assay. Delayed p53 stabilization at 4 hours postirradiation in one R-H subject suggested that different etiologies may apply in the radiohypersensitivity investigated in this study.     

Finding "Meaning" in Psychology: A Lay Theories Approach to Self-Regulation, Social Perception, and Social Development.

Much of psychology focuses on universal principles of thought and action. Although an extremely productive pursuit, this approach, by describing only the "average person," risks describing no one in particular. This article discusses an alternate approach that complements interests in universal principles with analyses of the unique psychological meaning that individuals find in their experiences and interactions. Rooted in research on social cognition, this approach examines how people's lay theories about the stability or malleability of human attributes alter the meaning they give to basic psychological processes such as self-regulation and social perception. Following a review of research on this lay theories perspective in the field of social psychology, the implications of analyzing psychological meaning for other fields such as developmental, cultural, and personality psychology are discussed. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Topology of the principal EEG elements of sleep analyzed by analogue filters

In order to compare the venodilation effect of morphine in normal individuals (22) with that in patients (13) with heart failure morphine sulfate (0.1 mg/kg) was administered to 13 patients with mild pulmonary edema. After morphine congestive symptoms improved and venodilation was induced as determined by two independent techniques: venous pressure fell 10.2 mm Hg by the isolated hand technique and the venous volume of the forearm increased by 0.48 cc/100 ml, measured by equilibration technique. Neither finding differed from those in normal individuals. Reflex venoconstriction noted on the taking of a single deep breath was unaffected by morphine administration and was similar to that observed in normal subjects. Since the drug morphine sulfate does not cause a major pooling of blood in the limbs, the favorable effect of narcotics in patients with pulmonary edema must be caused by other mechanisms such as splanchnic pooling, afterload reduction or reduced breathing effort.     

Brain imaging and age-related changes in cognition

Although there is currently some debate as to the degree of structural changes in the brain that occur with age, there is little doubt that such changes occur. There also are physiological changes in many areas that could have implications for cognitive function in the elderly. One way to study the impact of these age-related changes in the brain on cognition is to use neuroimaging techniques to examine brain activity during the performance of various tasks, and determine how this activity differs between young and older individuals. This approach has been used to study functions such as memory, perception, and attention, and it has generally been found that older individuals utilize different areas of the brain than do young subjects when carrying out the same cognitive task. This has led some researchers to suggest that older persons utilize different functional brain networks, perhaps to compensate for reductions of efficiency in some brain areas. The areas of the brain most often found to be more active during cognitive tasks in the elderly are the frontal lobes. Studies that have directly examined the functional networks utilized during cognition have found that older people do indeed have different functional interactions involving the frontal lobes, and therefore, utilize different functional networks. In some cases this differential activity has been accompanied by cognitive performance in the older participants that is equivalent to that seen in the young, suggesting that greater reliance on this brain region is related in some way to the maintained ability of the older individuals to perform the task. However, data collected to date on this issue are still limited, so although the evidence is intriguing, the definitive interpretation of these findings must await further experiments.     

The afterimages of "hallucinated" and "imagined" colors.

"These experiments indicate that another claim for the 'hypnotic transcendence of normal functions' is not substantiated. Some individuals 'hallucinate' a color and 'see' its appropriate afterimage after a minimal 'hypnotic induction procedure'; other individuals do essentially the same thing without a 'hypnotic induction procedure.' In fact, some Ss do better on this task without the 'hypnotic procedure.' However, these experiments also indicate that 'trance' behavior may be an essential component in 'projecting' or 'hallucinating' colors." (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Obesity: Responding to the global epidemic.

Obesity has reached epidemic proportions in the United States and other developed nations. In the United States, 27% of adults are obese and an additional 34% are overweight. Research in the past decade has shown that genetic influences clearly predispose some individuals to obesity. The marked increase in prevalence, however, appears to be attributable to a toxic environment that implicitly discourages physical activity while explicitly encouraging the consumption of supersized portions of high-fat, high-sugar foods. Management of the obesity epidemic will require a two-pronged approach. First, better treatments, including behavioral, pharmacologic, and surgical interventions, are needed for individuals who are already obese. The second and potentially more promising approach is to prevent the development of obesity by tackling the toxic environment. This will require bold public policy initiatives such as regulating food advertising directed at children. The authors call not for the adoption of a specific policy initiative, but instead propose that policy research, based on viewing obesity as a public health problem, become a central focus of research. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Memory for individuals: Hamsters (Mesocricetus auratus) require contact to develop multicomponent representations (concepts) of others.

In humans, individuals recognize other individuals by numerous types of independent information, such as the quality of the voice, appearance of the face, smell, gait, and posture. Humans also have integrated memories of others--that is, in response to a face or a voice the individual is recognized by name and other information about that individual is remembered. In many nonhuman species, individual recognition also occurs. Although observational studies suggest that individuals of some nonhuman species may be able to use several different cues for individual recognition, little experimental proof for this is available. Golden hamsters have at least 5 individually distinctive odors and they develop integrated, multi-odor memories (concepts) of familiar individuals, as shown by across-odor habituation experiments. Little is known, however, about the conditions that are necessary to develop such integrated memories. In these experiments we investigated what kinds of experiences were necessary for male hamsters to develop multiodor memories of females. The results show that exposure to all of the odors of another individual was not sufficient to develop such multiodor memories but that physical contact between the subjects and stimulus animals was necessary. Multiodor representations were developed after interactions with anesthetized individuals, confirming the finding that physical contact was important but also showing that interaction with an awake, behaving individual was not necessary to form multiodor representations of other individuals. We are not aware of experimental proof for integrated, multicomponant memories in any other nonhuman species. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Using full matching to estimate causal effects in nonexperimental studies: Examining the relationship between adolescent marijuana use and adult outcomes.

Matching methods such as nearest neighbor propensity score matching are increasingly popular techniques for controlling confounding in nonexperimental studies. However, simple k:1 matching methods, which select k well-matched comparison individuals for each treated individual, are sometimes criticized for being overly restrictive and discarding data (the unmatched comparison individuals). The authors illustrate the use of a more flexible method called full matching. Full matching makes use of all individuals in the data by forming a series of matched sets in which each set has either 1 treated individual and multiple comparison individuals or 1 comparison individual and multiple treated individuals. Full matching has been shown to be particularly effective at reducing bias due to observed confounding variables. The authors illustrate this approach using data from the Woodlawn Study, examining the relationship between adolescent marijuana use and adult outcomes. (PsycINFO Database Record (c) 2010 APA, all rights reserved)