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PubMed2001

Commentary: is the concept of "tumor promotion" a useful paradigm?

Since the demonstration of the multistage nature of carcinogenesis in experimental work on mouse skin carcinogenesis (and subsequently on various other organ systems in other organisms), the concepts of "initiation", "promotion", and "progression" were operationally generated from empiric data. Because these early observations and concepts had no mechanistic explanations, various hypotheses have been generated to explain the unique characteristics of each phase (e.g., initiation, being irreversible, was ascribed as the result of DNA damage leading to mutagenesis; promotion, being interruptible or reversible, was believed to be caused by epigenetic mechanisms; progression, also being irreversible, was believed to be caused by genetic instability that led to mutagenic and epigenetic changes). In addition, many of the molecular, biochemical, and cellular experiments designed to investigate the mechanistic bases of these phases used technologies that did not always lead to unequivocal interpretations, and because "real-life" carcinogenesis does not mimic controlled experimental conditions of the initiation/promotion/progression experiments, many investigators believe that these concepts have lost their usefulness. In this commentary, I explain some of the confusion concerning the concept of promotion and suggest that, by understanding the limitations of many in vitro assays used to characterize mutagens, by integrating other theories of carcinogenesis (i.e., stem cell theory), and by recognizing the role of epigenetic agents, specifically, modulated gap-junctional intercellular communication, the concept of promotion can provide valuable insights into the carcinogenic process. Mol. Carcinog. 30:131--137, 2001.

Animals↗
PubMed1975

A developmental study of Piaget's groupement model of the emergence of speed and time concepts.

3 key predictions of Piaget's groupement model of middle-childhood cognition were examined in the speed and time concept areas: (a) The respective composition and reverse operations of 2 of the 8 structures posited in the groupement model (Groupement I and Groupement V) should emerge synchronously in each of the 2 concept areas. (b) The 2 structures themselves should emerge synchronously in each of the 2 concept areas. (c) Between the 2 concept areas, the 2 structures should both emerge in the speed area before either emerges in the time area. The findings failed to support either prediction a or prediction b, and they were only partially consistent with prediction c. However, the findings concerning predictions a and b were consistent with other recent developmental evidence on the emergence of groupement structures in concept areas other than speed and time.

Age Factors↗
PubMed2001

Adaptive evolutionary conservation: towards a unified concept for defining conservation units.

Recent years have seen a debate over various methods that could objectively prioritize conservation value below the species level. Most prominent among these has been the evolutionarily significant unit (ESU). We reviewed ESU concepts with the aim of proposing a more unified concept that would reconcile opposing views. Like species concepts, conflicting ESU concepts are all essentially aiming to define the same thing: segments of species whose divergence can be measured or evaluated by putting differential emphasis on the role of evolutionary forces at varied temporal scales. Thus, differences between ESU concepts lie more in the criteria used to define the ESUs themselves rather than in their fundamental essence. We provide a context-based framework for delineating ESUs which circumvents much of this situation. Rather than embroil in a befuddled debate over an optimal criterion, the key to a solution is accepting that differing criteria will work more dynamically than others and can be used alone or in combination depending on the situation. These assertions constitute the impetus behind adaptive evolutionary conservation.

Animals↗
PubMed2002

The child's awareness of the concept of mental disease. A case study.

In international literature not many papers discuss the comprehension of the mental disease concept by children and their ability to understand its behavioral and ethical consequences. A knowledge of this domain could be very important for health professionals and practitioners who have to cope with children abused by adult relatives with psychiatric illnesses. The case study of an 8 year-old girl describes a brief child training, projected to facilitate the recovery of the child mother relationship, through the child's comprehension of the concept of mental disease. The girl was initially assessed in a child psychiatric clinic after a period of hospitalization caused by a severe physical aggression committed by the mother during an acute schizophrenic episode (an attempt of homicide and suicide). Post Traumatic Stress Disorder (PTSD) and other psychopathologies were absent in the child. The training project included: 1) the achievement of a confidential relationship between the girl and the doctor, 2) the child's comprehension of the general concept of illness, 3) the child's comprehension of the concept of mental illness and the absence of responsibility relative to the bizarre and aggressive behavior of the psychiatric patient. After 2 months of child training, the girl showed a partial but sufficient comprehension of the concept of mental illness. Hence, the girl successfully restored her relationship with the mother, without developing any psychopathological effects. This result was confirmed after one year.

Attitude to Health↗
PubMed2002

Automated concept matching between laboratory databases.

To address the problem of semantic inconsistencies between medical databases, semantic network representations can be utilized to automate the matching of medical concepts between the databases. The performance of automated concept matching was tested by creating semantic network representations for two laboratory databases, one from a pediatric hospital and the other from an oncology institute. The matching algorithms identified all equivalent concepts that were present in both databases, and did not leave any equivalent concepts unmatched. By automatically identifying semantically equivalent concepts, the Medical Information Acquisition and Transmission Enabler (MEDIATE) facilitates data exchange between heterogeneous systems because no pre-negotiation is required. Consequently, system scalability and stability is improved.

Algorithms↗
PubMedDate not supplied

Being with woman: A guiding concept for the care of laboring women.

OBJECTIVE: To review the literature concerning the midwifery concept of being with woman and the related nursing concepts of presence and social support during childbirth. DATA SOURCES: Literature in the English language from 1985 through 2000, using MEDLINE and CINAHL. DATA EXTRACTION: Discussion of articles from relevant journals and textbooks were included. Pertinent older sources, which enhanced the understanding of the concepts, were reviewed. DATA SYNTHESIS: Being with woman is defined as the provision of emotional, physical, spiritual, and psychological presence/support by the caregiver as desired by the laboring woman. Ample evidence exists for including being with woman as a central concept of the model of care for women in labor. The qualitative review indicates that women value and desire the attributes of the concept during childbirth. The qualitative and quantitative literature demonstrate beneficial physiological and psychological outcomes for women who experience being with woman. CONCLUSIONS: Obstetric units would be wise to incorporate the being with woman model of care as routine policy for the care of laboring women by midwives and nurses. Being with woman provides psychological and physiological benefits for women, client satisfaction, and potential cost savings.

Delivery, Obstetric↗
PubMed1976

A modification of a continuous time model for first conception.

The interval between marriage and the first conception leading to a live birth plays an important role in the determination of fertility components. Several probability models (Potter and Parker, 1964; Singh, 1961, 1964, 1967) based on varying sets of assumptions relating to this interval have been propounded in the recent past. All of them are based on the assumption that the females under study are susceptible to conception at the time of marriage. However, in certain situations, where some of the females already pregnant at the time of marriage report to have conceived within a short interval following marriage, this condition is not satisfied and these models become unsuitable. A probability distribution which is an inflated form of the continuous model proposed by Singh, for the time of the first conception leading to a live birth, is presented in this paper. It describes reasonably well the data on first conception times in the context of premarital conceptions. Simple expressions for the maximum likelihood estimators of the parameters involved in the model are obtained and a method for finding the asymptotic covariance matrix of the estimators is outlined. The model is applied to four sets of data.

Female↗
PubMed2002

Sexual health: the emergence, development, and diversity of a concept.

The concept of sexual health, which was developed at a 1975 conference of the World Health Organization (WHO), is currently being used to set up nationally based public health programs in various countries. I outline the history of sexuality as a public health issue since the 19th century, analyze the history of the concept of sexual health since its emergence in 1975, and make a comparative analysis of the contemporary documents dealing with sexual health generated in the U.S. and England, and by organizations such as the WHO and the Pan American Health Organization (PAHO). The analysis of these documents gives evidence that there is no international consensus on the concept of sexual health and its implementation in public health policies. The conceptions of sexual health remain embedded in national and political contexts. Conceptions for sexual health appear to be the result of political compromises and take place in the public health culture and practice of each country. Depending on the context, these different initiatives focus either on individual responsibility or on an appropriate sexual health services organization, and sexual health may be conceived as an ideal state of well-being or as the reduction of negative consequences of sexual activity.

Attitude to Health↗
PubMed1992

Endometrial dating in the conception cycle.

OBJECTIVE: To investigate endometrial dating during the conception cycle. DESIGN: Endometrial biopsies of the last half of the luteal phase of conception cycles were dated based on urinary luteinizing hormone (LH) surges. SETTING: Endometrial samples were obtained from women attending the fertility clinic of the Department of Obstetrics and Gynecology at Gunma University Hospital. PATIENTS: One hundred eighty-five women, of whom 15 (8.1%) conceived during this study. MAIN OUTCOME MEASURES: Urinary LH surge, serum progesterone (P) levels, and endometrial dating. RESULTS: All 10 women who conceived showed 2 or within 2 days in-phase endometrial biopsies on days 7 to 11 after the LH surge. In 4 of 5 women biopsied on day 12, an unequivocally delay in the stroma was found, i.e., a persistence of edema and poor development of predecidual reaction. Since serum P levels in conception cycles were significantly higher than in nonconception cycles on days 10, 11, and 12, we interpreted this delay in the stroma as a consequence of conception. CONCLUSION: Endometrial specimens during the last half of the luteal phase of conception cycles are in-phase until day 12. On day 12, gestational hyperplasia causes apparent out-of-phase.

Adult↗
PubMed2003

A study of biomedical concept identification: MetaMap vs. people.

Although huge amounts of unstructured text are available as a rich source of biomedical knowledge, to process this unstructured knowledge requires tools that identify concepts from free-form text. MetaMap is one tool that system developers in biomedicine have commonly used for such a task, but few have studied how well it accomplishes this task in general. In this paper, we report on a study that compares MetaMap's performance against that of six people. Such studies are challenging because the task is inherently subjective and establishing consensus is difficult. Nonetheless, for those concepts that subjects generally agreed on, MetaMap was able to identify most concepts, if they were represented in the UMLS. However, MetaMap identified many other concepts that peo-ple did not. We also report on our analysis of the types of failures that MetaMap exhibited as well as trends in the way people chose to identify concepts.

Abstracting and Indexing↗
PubMed2004

[Medical implications of the lay concepts of health: children's opinions of health and illness].

INTRODUCTION: Lay concepts of health and illness give additional important information to the biomedical models. According to the literature of lay beliefs, these concepts significantly affect population's health and illness behaviors and their health consciousness. Detecting children's lay concepts of health means a special professional challenge since they are not able to think in an abstract and systematic way yet, particularly to express this verbally. The draw-and-write method, which is based on projective technique, enables us to map children's lay concepts of health in their 8-10 years of age. AIMS: The main goal of the present qualitative research is to detect 8-11-year-old children's lay concepts of health, illness and risks, by using a technique which has already been accepted and applied at international level. METHODS: Data collection of the qualitative research was going on in two middle sized places of Békés county (Békés and Köröstarcsa), in the second half of 2003. The sample consisted of 128 elementary and middle school students (57% males and 43% females) from years 3-4-5, one class from each place and school grade. RESULTS: Most children apply a mixture of the biomedical and holistic health definitions. Many of them also emphasize the role of healthy lifestyle. In this age, health basically is related to infections since children possess of own experiences primarily about this type of disease. Most frequently children receive information of health and illness from their parents and physicians. CONCLUSION: These findings support earlier findings from international literature that 9-10-year-old children have a significant base of knowledge about health, illness and disease-inducing factors.

Child↗
PubMed2005

The pangenome concept: a unifying view of genetic information.

A way of viewing the genetic information in all organisms on Earth as constituents of the Pangenome is proposed. According to this concept, the Pangenome is the common (collective) genetic system of all living organisms, the organic molecules and their complexes (DNA- and RNA-containing viruses, plasmids, transposons, insertion sequences) involved in the storage and transmission processes of genetic information. Pangenomic stability and variability are discussed. This concept alerts to the inherent fluidity and transmissibility of DNA among organisms of all types, including horizontal gene transfer between closely related and formally unrelated macro- and microorganisms. The roles of death and of all known food chains as universal ways of gene distribution among different organisms are discussed. The contribution of bacteria and viruses in maintaining the circulation of genes within the Pangenome is presented. This concept implies that newly emerging genes are not bound to disappear together with the death of an organism or the extinction of a species and microorganisms are the main pool of genes. Some negative aspects of the intervention of molecular genetics, biotechnology, and ecology, including the spread of transgenic plants and animals, are summarized. It is shown that this concept may be used in medicine for the prognosis of an epidemic situation, particularly newly spreading pathogens, and for the development of new methods for the prophylaxis and early diagnosis of oncologic diseases. This concept can also help to find promising approaches to the discovery of drugs with novel principles of action.

Animals↗
PubMed2006

Efficacy of the symmetric, patient-oriented, rigid, three-dimensional, active (SPoRT) concept of bracing for scoliosis: a prospective study of the Sforzesco versus Lyon brace.

AIM: Bracing is considered to be effective in the treatment of adolescent idiopathic scoliosis. The concept prevailing today includes an asymmetrical construction, mainly using a mechanical three-point system. We developed the new Sforzesco brace, based on the SPoRT concept (Symmetric, Patient-oriented, Rigid, Three-dimensional, active). The aim of this study is to verify the results of this concept and brace, compared to three-point classical systems. METHODS: We performed a prospective, pair-controlled study. It was possible to match 15 patients, out of the first 18 consecutively treated with the Sforzesco brace (Group SPoRT), with previous patients treated with the Lyon brace (Group LY). SPoRT included 14.2+/-1.7 year old patients, with 47+/-7 degrees Cobb worst curves, and 11+/-4 degrees Bunnell; LY included 13.6+/-1.6 year old patients, with 43+/-7 degrees Cobb and 12+/-5 degrees Bunnell. The brace had to be worn 23 h per day and patients were evaluated after 6 months both clinically and radiographically (without the brace). Appropriate statistics were used. RESULTS: At the baseline there were slight differences between the groups, with SPoRT worse than LY. All radiographic and clinical parameters decreased significantly with treatment in both groups, apart from thoracic Cobb degrees in LY. SPoRT had better results than LY (P<0.05) radiographically (worst curve -10+/-5 degrees vs -5+/-7 degrees, all curves -8+/-7 degrees vs -6+/-7 degrees), for sagittal profile (distance from plumbline: T12 -6+/-9 mm vs +2+/-8 and L3 -7+/-12 vs 0+/-10) and aesthetics of the shoulders (9 improved and 6 unchanged vs 5 and 8) and waists (10 improved and 5 unchanged vs 5 and 8). Finally, clinical results in terms of patient recovery were better in SPoRT than LY (12 improved and 3 unchanged vs 8 and 5). CONCLUSION: When a new treatment is introduced, it is not possible to wait years (end of therapy) before verifying its utility, and in scoliosis bracing a short term study already gives very important clues. This study confirms the immediate efficacy of brace treatment (even in such high degree cases) whatever the brace concept used, with only 2 (out of 30) progressed curves. In SPoRT we had no progressions, and obtained a statistically significant 80% better radiographic results than LY in the worst scoliosis curve, and 40% in the average of all curves, as well as improved aesthetics and sagittal profile (that is crucial in scoliosis bracing). The Sforzesco brace should be used, and the SPoRT concept explored in the long term to verify if the classical three-point system should be totally (or partially) abandoned.

Adolescent↗
PubMed1991

Time of onset of post-partum luteal function and conception in dairy cows.

The following reproductive parameters were studied in 40 Icelandic dairy cows on 2 farms with free stall and tie stall housing: The time of onset of post-partum luteal activity; the time of first post-partum artificial insemination (AI); the time of conception; conception rate to first post-partum AI; the number of AI's per conception; length of gestation; and the number of days between 2 consecutive calvings. Milk for progesterone analysis was sampled 3 times a week from calving until first AI on farm 1, but every day for 90-100 days from calving on farm 2. In this study the average onset of luteal function was 21 days post-partum, the cows were inseminated 62 days and conceived 74 days post-partum. Conception rate to first AI was 71% and number of AI's per conception was 1.6. Significant differences were not found between the 2 farms. The reproductive performance of the cows in this study was greater than found in earlier studies of the Icelandic dairy cows and indicate that this animal has reproductive capabilities comparable to high producing foreign dairy cows.

Animals↗
PubMed1991

A preliminary study of health conceptions among married women.

The purpose of this study is to assess the consistency of the dimensions of health identified in the study with Smith's four models of the meaning of health perception and to determine the variation in health conceptions as related to women's age, education, employment status and self-rated health status. A convenience sampling was used in this study that included 86 married women between the ages of 24 and 50, with a mean age of 33 years (SD = +/- 6.1). Of 86 women, 58 were from the Kaohsiung Medical College Hospital, and 28 were from Ma Ma Yuan Di, a women's self-developing club. Interviewing, performed by two research assistants, took place in the women's homes. The findings indicate that the most frequently mentioned women's concepts of health support Smith's clinical model (73.3% of the 86 women). The eudaemonistic model, which includes the practicing of healthy lifestyles, was the second most frequently mentioned concepts of health (53.5%). The other two models, role-function and adaptive, were seldom mentioned by the women (12.8% and 4.7% respectively). The conceptions of health were divided into two groups. The negative group includes clinical and role-function models, and the positive group includes adaptive and eudaemonistic models. No significant association was found between health conceptions and age, education, employment status and self-rated health status through Chi-Square analysis.

Adult↗
PubMed1991

Pre-conception management of insulin-dependent diabetes: improvement of pregnancy outcome.

Poor glycemic control in early pregnancy in insulin-dependent diabetes is associated with an increased risk for spontaneous abortions and congenital malformations. Strict glycemic control from the initial stages of embryogenesis is one of the major goals of management in these pregnancies. We hypothesized that insulin-dependent diabetic patients attending a pre-conception program would have improved glycemic control compared with insulin-dependent diabetic patients who enrolled after conception and would have better pregnancy outcome, with fewer spontaneous abortions and fewer major malformations. Ninety-nine pregnant insulin-dependent diabetic patients were recruited before reaching 9 weeks' gestation and were followed prospectively throughout pregnancy. Twenty-eight had attended a pre-conception clinic to optimize glycemic control (study group) and 71 had enrolled after conception (control group). Early glycemic control was significantly better in the study group: Glycohemoglobin values at the first prenatal visit and at 9 and 14 weeks' gestation were significantly lower than in the control group. The rate of spontaneous abortion was significantly lower in the study group (7%) than in the controls (24%). There was one major malformation in the control group and none in the study group. We conclude that patients with insulin-dependent diabetes attending a pre-conception program have a decreased rate of early pregnancy loss compared with those receiving prenatal care early in pregnancy.

Abortion, Spontaneous↗
PubMed1990

[General concepts and the history of chronic obstructive pulmonary disease].

There is no general agreement on the concepts of chronic obstructive pulmonary disease (COPD) yet in Japan, although there have been significant advances in the understanding of its concepts in the United States and Europe. The purpose of this presentation as the opening remark to this panel discussion is to review the concepts and history of chronic obstructive pulmonary disease (Tables 1, 2), and also to summarize the general concepts concerning COPD in Japan at present. More than 30 years ago, a Ciba Guest symposium first proposed the main subdivisions of chronic non-specific lung disease (CNSLD), consisting of chronic bronchitis and generalized obstructive lung disease (GOLD). Many papers addressed this theme focusing on the definition and concepts of COPD for a long period after the Ciba Guest Symposium. The ATS and ACCP joint committee on pulmonary nomenclature (1975) reported that the term of COPD refers to diseases of uncertain etiology characterized by persistent slowing of airflow during forced expiration, and the committee recommended that chronic obstructive bronchitis or chronic obstructive emphysema be used, whenever possible. However, in many patients it is still difficult determine what extent the airway obstruction result from emphysema and to what extent it results from an accompanying chronic obstructive bronchitis, as Burrows described. Fishman (1980) and Burrows (1981) suggested that if the patient is thought to have a combination of chronic obstructive bronchitis and pulmonary emphysema, the case should be so diagnosed.(ABSTRACT TRUNCATED AT 250 WORDS)

Europe↗
PubMed1989

[Repeated peritoneal lavage in necrotizing pancreatitis. Preliminary experiences with a new therapy concept].

A retrospective report on experience with patients with hemorrhagic necrotizing pancreatitis treated surgically with the new therapeutic concept of programmed lavage, so-called, is presented. With the exception of one fatality, using an unchanged intensive care therapy program, 7 patients were successfully treated with the new concept. Since the results obtained with the therapeutic concept used prior to the technique of programmed lavage, as also reports in the international literature, are associated with a very poor prognosis, it is suggested that this new treatment concept be employed with the aim of improving the prognosis. A definitive assessment of this concept will, however, require a large number of cases treated in this way.

Acute Disease↗