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PubMed2000

Limitations of Rechtschaffen and Kales.

The guidelines of Rechtschaffen and Kales (R&K) were meant as a reference method. However, it became, unintentionally, a gold standard. The rules have never been appropriately validated. It is used for the scoring of recordings of, for instance, pathological sleep, for which it was not designed. Today R&K is an insufficient description of sleep processes. In practice, the rules are often difficult or impossible to follow and deviations are common, although not reported. The major drawbacks are: low temporal resolution, ignorance of spatial information, insufficient number of stages, low correspondence between electrophysiological activity and stages, and ignorance of other physiological parameters such as autonomous nervous system activity and body motility. The original idea of the committee should be followed; the guidelines should be revised with the accumulation of new knowledge and development of technology. This is especially true for the analysis of delta waves, which should replace visual scoring of the NREM sleep stages. Many of the problems related to the use of the manual are not due to the system itself but the way it has been applied. This has evidently had a serious impact on the way of thinking and the development of the field in general.

Journal Article↗

PubMed1988

Panic disorder: review of the empirical and rational basis of pharmacological treatment.

The increasing interest in and clinical research on the nature and treatment of panic disorder and agoraphobia have produced and should continue to produce rapid progress in the accumulation of scientific knowledge in this field. This article reviews some basic aspects of the effective pharmacotherapeutic management of panic-agoraphobic patients. Research results with different drug classes are reviewed and their implications for effective treatment discussed. The final section deals with special issues of case management, such as choice of specific drug, length of treatment, and probability and frequency of relapse.

Fear↗

PubMed1998

The interaction between leptin and the hypothalamic-pituitary-thyroid axis.

The description of the adipose tissue hormone leptin has led to important discoveries. Leptin plays a role not only in the regulation of metabolic efficiency, energy expenditure, food intake and adiposity, but also contributes greatly to the adaptation of the organism to starvation. Much of the literature has focused on the physiologic roles of leptin-driven processes as diverse as feeding behavior, body weight, defense to starvation and reproduction. The following discussion summarizes knowledge that has accumulated regarding the interaction between leptin and the hypothalamic-pituitary-thyroid axis.

Adipose Tissue↗

PubMed1998

MRI of Normal Variants and Interpretation Pitfalls of the Elbow.

One of the fundamental principles of MR imaging interpretation is the ability to distinguish normal anatomical landmarks from true disease. The radiologist is thus compelled to accumulate a comprehensive knowledge of normal structures, variants, and potential MRI diagnostic pitfalls.1-5 In this article we will focus on a number of normal bony, ligamentous, and tendinous structures that can simulate disease at the elbow. We discuss the particular anatomy responsible for the appearance of each of these interpretation pitfalls as well as the distinguishing features between these normal variants and true disease.

Journal Article↗

PubMed2006

Equine cloning: applications and outcomes.

Cloning is one of several new assisted reproductive techniques being developed for clinical use in the equine industry. Potential uses of equine cloning include: (1) the preservation of genetics from individual animals that would otherwise not be able to reproduce, such as geldings; (2) the preservation of genetic material of endangered and/or exotic species, such as the Mongolian wild horse (Przewalski's horse); and (3) because of the companion animal role that horses fill for some individuals, it is likely that some horse owners will have individual animals cloned for emotional fulfillment. Although equine cloning has been successful, like other species, it remains a very inefficient process (<3% success). In most species, the inefficiency of cloning results from a high incidence of embryonic, fetal and/or placental developmental abnormalities that contribute to extremely high rates of embryonic loss, abortion and stillbirths throughout gestation and compromised neonatal health after birth. The present review describes some of the ultrasonographic, endocrinological and histopathological characteristics of successful (produced viable offspring) and unsuccessful (resulted in pregnancy failure) cloned equine (mule and horse) pregnancies we have produced. A total of 21 cloned mule pregnancies were established using fetal fibroblast cells, whereas a total of seven cloned horse pregnancies were established using adult cumulus cells. Three of the cloned mule conceptuses were carried to term, resulting in the birth of three healthy clones. This information adds to an accumulating body of knowledge about the outcome of cloned equine pregnancies, which will help to establish when, and perhaps why, many cloned equine pregnancies fail.

Abortion, Spontaneous↗

PubMed2002

Global view on functional foods: European perspectives.

In the context of this presentation, European means the European scientific community, which, over the last decade, has been working on the concepts for functional foods, producing a number of documents including a consensus paper, guidelines and scientific publications. The Functional Food Science in Europe (FUFOSE) project has been quite a unique attempt to establish a strong scientific framework to justify the functional food concept, to discover and develop new functional foods that are primarily function-driven, and to substantiate claims scientifically. Being clearly positioned as part of nutrition, the functional food concept is, however, quite distinct from other approaches like food supplementation or food fortification, and functional foods are different from nutraceuticals, pharmafoods, vitafoods and 'alicaments', all terms that are not defined conceptually. Functional foods are food products to be taken as part of the usual diet in order to have beneficial effects that go beyond what are known as traditional nutritional effects. Moreover, these beneficial effects have to be demonstrated scientifically to justify two specific types of claim: the enhanced function claim or the reduction of disease risk claim. Functional food is a key concept for the future of nutrition as a science because it results from the implementation in nutrition of all the basic scientific knowledge that has accumulated over the past two or three decades. To the benefit of public health this progress cannot be ignored, it needs to be recognized fully and used. But, today, functional food is still mainly a scientific concept that serves to stimulate research and the development of new products.

Biotechnology↗

PubMed1999

Pathogenic mechanism of acute post-streptococcal glomerulonephritis.

Considerable knowledge has been accumulated regarding the characteristics of acute post-streptococcal glomerulonephritis (APSGN), and many attempts have been made to identify a streptococcal factor or factors responsible for triggering this disease. However, the pathogenic mechanism behind APSGN remains largely unknown. As glomerular deposition of C3 is generally demonstrated before that of IgG in the disease process, it is likely that the inflammatory response is initiated by renal deposition of a streptococcal product, rather than by deposition of antibodies or pre-formed immune complexes. During recent years, a number of streptococcal products have been suggested to be involved in the pathogenic process. In this review, possible roles of these factors are discussed in the context of the clinical and renal findings most often demonstrated in patients with APSGN. Streptokinase was observed to be required in order to induce signs of APSGN in mice, and a number of findings suggest that the initiation of the disease may occur as a result of renal binding by certain nephritis-associated variants of this protein. However, additional factors may be required for the development of the disease.

Acute Disease↗

PubMedDate not supplied

Perimenopause: the transition into menopause.

With an ever-accumulating body of knowledge about menopause has come the realization that the transition into menopause, specifically the perimenopausal period, is a process occurring over a period of years. We now know that the majority of women do not move from a time of regular menses to an abrupt cessation of menses. Rather, they experience perimenopause, a time of menstrual irregularity defined by changes in the length of the menstrual cycle and/or changes in level of discomfort associated with menses. We also know now that hormonal levels during the perimenopausal period may fluctuate more intensely, precipitating vasomotor and other symptoms. There is a tremendous need to educate women and their health care providers about the stages of the menopausal process. Such education will foster understanding of when women can expect the onset of perimenopausal symptoms. Health care providers should assist women with their questions and concerns as they move through this time of transition.

Adult↗

PubMed2001

Any further progress in smoking cessation treatment?

The release of the US Public Health Service's quantitative review of smoking treatments, Treating Tobacco Use and Dependence (TTUD; Fiore, Bailey, Cohen et al., 2000, AHRQ Publication, USDHHS), is a fitting occasion to revisit a question posed by Shiffman (1993, Journal of Consulting and Clinical Psychology, 61:718-722): has there been any recent progress in smoking cessation treatment? Using TTUD meta-analyses as a rough guide, we present an overview of current elements of clinical treatments (structure, content, and pharmacotherapy) with statistical claims to efficacy. We note characteristics of treatment, or treatment research, that may retard accumulation of critical knowledge, including the hegemony of multi-component treatments and a seeming disinterest in treatment process. Finally, we sketch avenues of potentially generative research that might foster new insights and improved treatments. It is concluded that not much has changed since Shiffman's (1993) review, and that his call for a rededication to basic research is still prudent but largely unanswered.

Humans↗

PubMed2003

Symptom management in cancer: pain, depression and fatigue: State-of-the-Science Conference Statement.

NIH Consensus Statements are prepared by a nonadvocate, non-Federal panel of experts, based on (1) presentations by investigators working in areas relevant to the consensus questions during a 2 day public session; (2) questions and statements from conference attendees during open discussion periods that are part of the public session; and (3) closed deliberations by the panel during the remainder of the second day and morning of the third. This statement is an independent report of the panel and is not a policy statement of the NIH or the Federal Government. The statement reflects the panel's assessment of medical knowledge available at the time the statement was written. Thus, it provides a "snapshot in time" of the state of knowledge on the conference topic. When reading the statement, keep in mind that new knowledge is inevitably accumulating through medical research.

Analgesics↗

PubMedDate not supplied

Malaria: host-pathogen biology.

The development of resistance to insecticides by anopheline mosquito vectors of malaria and of resistance to drugs by Plasmodium falciparum pose new challenges for malaria control programs. The establishment of methods for the continuous cultivation in vitro of plasmodia provided an important new tool for research into the cellular biology and metabolism of these parasites. The molecular basis of the parasite's attachment to and entry into erythrocytes in the host is being elucidated. The impact of the intracellular parasite on erythrocyte metabolism is being explored, and the recognition of the role of plasmodia as an oxidant stress suggested a molecular basis for certain forms of genetic resistance to malaria. In addition, the consequences of parasitization are being studied with regard to alterations in erythrocyte antigenicity, rheologic properties, and the transport of nutrients and antimalarial drugs. The host's immune response to malaria is being assessed with regard to both protective and immunosuppressive effects. The rapid accumulation of new knowledge of host-parasite biology could provide the basis for the design of novel pharmacologic and immunologic methods for the control of malaria.

Animals↗

PubMed1994

The pseudotumor cerebri.

Pseudotumor cerebri is the most appropriate term yet devised for classifying clinical patterns marked by papillary edema, uni- or bilateral, without major clinical signs and with normally sized cerebral ventricles, in which clinical or radiological investigations have ruled out the presence of a space occupying lesion of infective process. Because pseudotumor cerebri is a syndrome and its etiologies are many and varied, it is still difficult to make a diagnosis other than by exclusion. However, the knowledge that has accumulated as a result of epidemiological, clinical, neuroradiological, and experimental research enables us to say that the explanation of pseudotumor cerebri lies, on the one hand, in a sluggishness of the intracranial venous circulation with a consequent increase in cerebral blood volume and slowing of cerebrospinal fluid absorption and, on the other, in the onset of cerebral edema, either hypo-osmolar or vasogenic. The differing extent to which these three components participate in the clinical pattern depends on the etiology, but the resulting syndrome is always the same, though varying in clinical expression and pathogenesis.

Cerebrospinal Fluid↗

PubMed2004

The mechanism of Drosophila leg development along the proximodistal axis.

During development of higher organisms, most patterning events occur in growing tissues. Thus, unraveling the mechanism of how growing tissues are patterned into final morphologies has been an essential subject of developmental biology. Limb or appendage development in both vertebrates and invertebrates has attracted great attention from many researchers for a long time, because they involve almost all developmental processes required for tissue patterning, such as generation of the positional information by morphogen, subdivision of the tissue into distinct parts according to the positional information, localized cell growth and proliferation, and control of adhesivity, movement and shape changes of cells. The Drosophila leg development is a good model system, upon which a substantial amount of knowledge has been accumulated. In this review, the current understanding of the mechanism of Drosophila leg development is described.

Animals↗

PubMed2005

Plant immunophilins: functional versatility beyond protein maturation.

Originally identified as the cellular targets of immunosuppressant drugs, the immunophilins encompass two ubiquitous protein families: the FK-506 binding proteins or FKBPs, and the cyclosporin-binding proteins or cyclophilins. Present in organisms ranging from bacteria to animals and plants, these proteins are characterized by their enzymatic activity; the peptidyl-prolyl cis-trans isomerization of polypeptides. Whilst this function is important for protein folding, it has formed the functional basis for more complex interactions between immunophilins and their target proteins. Beginning with a brief historical overview of the immunophilin family, and a representative illustration of the current state of knowledge that has accumulated for these proteins in diverse organisms, a detailed description is presented of the recent advances in the elucidation of the role of this ubiquitous protein family in plant biology. Though still in its infancy, investigation into the function of plant immunophilins has so far yielded interesting results--as a significant component of the chloroplast proteome, the abundance of immunophilins located in the thylakoid lumen suggests that these proteins may play important roles in this relatively uncharacterized subcellular compartment. Moreover, the importance of the complex multidomain immunophilins in functions pertaining to development is underscored by the strong phenotypes displayed by their corresponding mutants.

Biological Evolution↗

PubMedDate not supplied

The pig as a source of cardiac xenografts.

The inadequate availability of human donor hearts and other organs has inspired interest in the field of xenotransplantation. Historically, ten attempts to transplant animal hearts into human recipients have been reported. Those who received hearts from nonhuman primates (i.e., baboons and chimpanzees) survived rather longer than did those who received hearts from nonprimates (i.e., sheep and pigs). Nevertheless, current opinion is that the pig is the best candidate as a source of hearts for humans despite the considerable immunologic disparity between the two species. Pigs are available in large numbers and can be bred easily and rapidly. They grow to appropriate sizes and their cardiovascular system is similar to that of humans. Substantial knowledge has been accumulated regarding both genetic engineering and tolerance induction in pigs, two strategies that may help to overcome the existing immunologic barriers. Concern has been raised, however, with regard to the potential for the transfer of a porcine infection with the pig organ to the human recipient. This brief review addresses these and other aspects of the use of the pig as a source of hearts for patients with end-stage cardiac disease.

ABO Blood-Group System↗

PubMed1995

The nomothetic-idiographic debate in family therapy.

This essay introduces the terms "nomothetic" and "idiographic" to characterize the current debate about whether the field of family therapy should accumulate and apply knowledge about patterns of adjustment that hold across different families, or whether the field should consider each family as utterly unique, and should tailor interventions solely on the basis of these unique qualities. Embedded in this debate are the arguments for and against quantitative research, disagreements about the value of clinical prediction and interobserver reliability, as well as the issue of whether therapists can rightfully claim to possess "expert knowledge." The essay begins with the personal-professional anecdote that stimulated me to explore this debate in greater depth. It continues with a brief discussion of the historical context of this debate, particularly noting the parallels between the methodological issues in personality research and those facing family therapy. The nomothetic-idiographic debate in family therapy theory, research, and practice is then described. The essay ends with the suggestion that family therapy view nomothetic and idiographic thinking as complementary, and that the field strive to develop an integrated, "idiothetic" approach to family therapy research and practice.

Adult↗

PubMed1997

"Broken Glass": the divorced woman in Moslem Arab society in Israel.

This article presents the findings of a preliminary, qualitative, exploratory study of divorce in Israeli-Arab society from the perspectives of divorced women living in Jaffa, Israel, and of Arab professionals engaged in therapeutic work. It explores the causes of divorce, the women's coping with the divorce process, and what constitutes post-divorce adjustment, based on the experiences of nine divorced Moslem Arab women and the input of six Arab professionals. The women attributed their divorces to extreme external factors: their husband's substance abuse, mental illness, and/or severe physical violence against them, as well as to interference by their husband's family of origin. They told of coping by relying on their inner resources and the strength their children gave them, while their own families of origin were almost uniformly critical and rejecting. They defined post-divorce adjustment as passing the test of female honor posed by their community, which they did by downplaying their femininity and immersing themselves in housework and childcare. The findings were compared with the research and clinical knowledge that has accumulated on divorce in Western society.

Adaptation, Psychological↗

PubMed1994

Artificial life extension. The epigenetic approach.

An epigenetic approach starts out from the direct (rather than the underlying genetic) causes. An epigenetic approach to aging has little chance of succeeding before a minimum amount of knowledge has been accumulated on the "genetic programming" that is currently believed to underlie aging. Two recent advances, one empirical and one theoretical, jointly brighten the prospect. The empirical one is the discovery that melatonin functions as an aging-controlling hormone in mammals. In 1979, Dilman and co-workers isolated a biologically active pineal extract (epithalamin) in rats which, as they later showed, stimulates melatonin production. Pierpaoli and co-workers in 1987 directly administered melatonin to mice. Both groups observed a surprising 25-percent increase of life span in conjunction with a postponed senescence. A similar effect was also achieved with an engraftment of young pineal tissue into the thymus of old mice by Pierpaoli's group. Beneficial effects of epithalamin in humans were reported by Dilman's group. The second advance is a deductive evolution-theoretical approach to aging discovered in 1988. In populations living in a niche with a fixed carrying capacity, any individual is in the long run replaced by a single successor. It follows that, as the expected cumulative number of adult progeny of the same sex approaches unity as a function of life time of the progenitor, the latter's survivability must approach zero if the sum is to remain unity. A physiological prediction follows: a centralized physicochemical clock--like a sedimentation process--must exist somewhere in the organism controlling a secreted substance that reaches all cells. In this way, the pineal coacervates and the pineal's hormonal product melatonin were arrived at on an independent route again. While melatonin as a drug has been used on human volunteers for decades, its anti-aging effect has yet to be proved. Detailed hormone profiles in different age groups and under different life styles have to be performed. A modified Hayflick in vitro experiment is also needed to elucidate the mechanism by which melatonin works in cells.

Aging↗