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In this 250-bed general hospital, nursing care for the dying focuses not on recovery but on self-actualization. In a broader context, patients also benefit from nursing's theory-based approach. A parallel between the evolution of the patient and the nursing process is established.
Popularity of the personal computer has prompted physician interest in direct access to the medical literature from sophisticated electronic data retrieval systems. This paper describes the educational programs developed by the library at the George Washington University Medical Center in response to this interest and growing national trend. As a result of these programs, the role of the librarian has changed permanently. Librarians are now perceived by faculty as educational specialists and information consultants. The evolution in libraries parallels the technological changes taking place in other biomedical communications units. The authors recommend the positive outcomes from adapting traditional roles to meet user's needs in a changing environment.
Thymic Nurse Cells (TNCs) are lymphoepithelial complexes which are thought to play a role in the early stages of the intrathymic differentiation pathway. Therefore, their repopulation kinetics were analyzed in mice after sublethal whole-body irradiation. Changes of the number of TNCs per thymus were parallel with the evolution of the whole thymocyte population. Particularly, a first wave of TNCs restoration was followed by a secondary depletion and a final recovery. This suggests that TNCs restoration is related to the proliferating progeny of intrathymic radioresistant thymocytes. When normal bone marrow cells were grafted intravenously after irradiation, no secondary depletion was found. This pattern of restoration was obviously related to thymic repopulation by cells which were derived from the inoculated bone marrow. Homing studies with FITC labelled bone marrow cells showed that inoculated bone marrow cells did not penetrate TNCs early after irradiation. Later on, when immigrant cells started to proliferate, they were found preferentially within TNCs before spreading in the whole thymus. The results indicate that interactions between immature thymocytes and epithelial cells within TNCs are critical for the first steps of intrathymic lymphopoiesis.
A conceptual treatment of the mechanisms involved in the process of toxicosis by diverse agents in different tissues indicate a likely unspecific, common, central process in addition to specific precipitating factors acting on a particular site in a cascade of events. Free radicals, membrane functions and calcium functions appear to be links in the common pathway. Such a central mechanism could be interrelated with immunological defenses as well as genotoxic changes at different sites, suggesting parallel or related evolution of these antistress mechanisms. Many radical scavengers, antioxidants, membrane stabilizers, nutritional supplements and calcium modulators have proved beneficial either in reducing toxic impact, delaying the development of lesions or even reversing the effects. Similarly, recent evidences show that some immunomodulators can act as antioxidants and antigenotoxicants. Thus, the status of body defenses which may vary from one individual to the other have a role in deciding the effects under the same quantified risks with varying relative responses. Whether modulation of physiological defenses against stress could help in developing prophylactic measures remains an open question.
Sixteen (16) patients with Familial Amyloidotic Polyneuropathy-Portuguese Type (FAP) were evaluated longitudinally, using the EMG and Clinical protocols with the aim of establishing the clinical and neurophysiological evolution rate of FAP. We conclude that spontaneous evolution of FAP patients shows a linear progression. Clinical and neurophysiological evolution times are parallel, with the EMG scores being higher than Clinical ones. We propose that Clinical and EMG scores should be used in the evaluation of future therapeutic trials, namely immunodepuration and liver transplantation.
HACCP is intended to make food protection programs evolve from a mainly retrospective quality control toward a preventative quality assurance approach and to provide an increased confidence in food safety. In parallel, the continuous evolution of quality concepts in the food industry resulted in the development of quality systems and quality assurance techniques with regard to the EN 29,000 (ISO 9000) series of standards. Specific to the food industry, HACCP can be seen as a very effective method to prepare specific Safety Assurance Plans (cf. the quality assurance plan concept) within a quality systems approach (Jouve, 1993). By reference to ISO 8402, a Quality Assurance Plan (QAP) basically sets out "the specific quality practices, resources and sequence of activities relevant to a particular product, service, contract or project". Quality assurance plans are more particularly useful for projects relating to new products or processes and/or comprising inter-related tasks whose interaction may be complex. In addition, in contractual or regulatory situations, such plans can be used to demonstrate the supplier's capability to meet identified objectives, specification or standards. In the food industry, the management of safety is a critical and complex issue which fits very well in the scope of application of a specific QAP; it is also where the use of HACCP is otherwise recommended by priority.
INTRODUCTION: Interstitial granulomatous dermatitis is a histological entity usually associated with systemic auto-immune conditions or malignant lymphoproliferation. Its spontaneous regression after surgical treatment of a lung cancer suggests an eventual paraneoplasic variant. OBSERVATION: A 62 year old male patient, a smoker, was hospitalized for weakness, pruritus and symmetrical arthritis of small and large joints. Numerous rheumatoid nodules were located on the extensor aspects of the involved joints. During hospitalization, he developed an inflammatory plaque located on a thigh, which showed histologic features consistent with the diagnosis of interstitial granulomatous dermatitis. He had elevated E.S.R., blood eosiniphilia, and the search for antinuclear antibodies and antineutrophilic leukocyte cytoplasm antibodies (ANCA), of the p-ANCA type, was positive. A lung C.T. scan showed a cavitary tumor. Surgical removal of this tumor evidenced a bronchial squamous cell carcinoma. Four week after surgery, clinical signs and eosinophilia disappeared. After 6 months, ANCA became undetectable. DISCUSSION: Parallelism between the evolution of the cutaneous and articular symptomatology and of the cancer are diagnosis of paraneoplastic rheumatoid arthritis and paraneoplastic interstitial granulomatous dermatitis. Paraneoplastic rheumatoid arthritis is very unusual and this is the first reported case of simultaneously occurring paraneoplastic interstitial granulomatous dermatitis.
Many examples of the appearance of similar traits in different lineages are known during the evolution of organisms. However, the underlying genetic mechanisms have been elucidated in very few cases. Here, we provide a clear example of evolutionary parallelism, involving changes in the same genetic pathway, providing functional adaptation of RH1 pigments to deep-water habitats during the adaptive radiation of East African cichlid fishes. We determined the RH1 sequences from 233 individual cichlids. The reconstruction of cichlid RH1 pigments with 11-cis-retinal from 28 sequences showed that the absorption spectra of the pigments of nine species were shifted toward blue, tuned by two particular amino acid replacements. These blue-shifted RH1 pigments might have evolved as adaptations to the deep-water photic environment. Phylogenetic evidence indicates that one of the replacements, A292S, has evolved several times independently, inducing similar functional change. The parallel evolution of the same mutation at the same amino acid position suggests that the number of genetic changes underlying the appearance of similar traits in cichlid diversification may be fewer than previously expected.
Twelve populations of Escherichia coli evolved in and adapted to a glucose-limited environment from a common ancestor. We used two-dimensional protein electrophoresis to compare two evolved clones, isolated from independently derived populations after 20,000 generations. Exceptional parallelism was detected. We compared the observed changes in protein expression profiles with previously characterized global transcription profiles of the same clones; this is the first time such a comparison has been made in an evolutionary context where these changes are often quite subtle. The two methodologies exhibited some remarkable similarities that highlighted two different levels of parallel regulatory changes that were beneficial during the evolution experiment. First, at the higher level, both methods revealed extensive parallel changes in the same global regulatory network, reflecting the involvement of beneficial mutations in genes that control the ppGpp regulon. Second, both methods detected expression changes of identical gene sets that reflected parallel changes at a lower level of gene regulation. The protein profiles led to the discovery of beneficial mutations affecting the malT gene, with strong genetic parallelism across independently evolved populations. Functional and evolutionary analyses of these mutations revealed parallel phenotypic decreases in the maltose regulon expression and a high level of polymorphism at this locus in the evolved populations.
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PURPOSE: To determine whether multivariable risk factor assessment can be as successful in developing disease prevention strategies in patients with ocular hypertension as it has been in patients at risk for coronary heart disease (CHD). DESIGN: From a literature review of the evolution of the global risk assessment model for CHD, parallels are drawn to the evolution of a global risk assessment methodology for glaucoma. METHODS: This article summarizes the literature on global risk assessment and prevention of CHD in clinical practice, discusses the development of glaucoma risk assessment based on available trial and population data, and reviews the potential for prevention strategies founded on the cardiovascular disease model. RESULTS: To improve risk assessment in glaucoma and develop disease management strategies for patients with ocular hypertension, it is first necessary to identify and quantify levels of risk associated with factors that predict disease progression. In addition, the incidence of glaucoma and the average person's life expectancy based on his or her age are needed. Finally, it is necessary to quantify how long it takes to develop a visual defect that affects quality of life once a person develops glaucoma. CONCLUSION: The systematic application of epidemiologic data to CHD risk factor models provides insights into how global risk assessment can be incorporated into treatment recommendations for managing individuals with glaucoma. It is hoped that ophthalmologists can use the results of future clinical trials and long-term studies to develop disease prevention strategies in patients with ocular hypertension based on multivariable risk assessment.
Genetic relationships among 25 species of Central and South American Bufo and among representative North, Central, and South American, Asian, and African Bufo were probed, using the quantitative immunological technique of microcomplement fixation (MC'F) which indicated a clear separation of North, Central, and South American lineages of Bufo. The South American lineage likely diverged from the Central and North American lineages in the Eocene; the latter two lineages diverged later, probably in the mid-Oligocene. Some species groups of South American toads, defined on the basis of traditional morphological studies, are genetically quite similar within groups, whereas others are genetically divergent. The amount of albumin evolution does not appear to parallel the amount of karyotypic, morphological, ecological, or behavioral evolution documented. Comparisons suggest that the African lineages separated from the American and Asian lineages in the late Cretaceous, corresponding to the time of the final separation of Gondwanaland, the southern supercontinent including the modern continents of South America, Africa, Australia, Antarctica, and India. The Asian lineages diverged from the lineage giving rise to all of the American species in the early Paleocene.
Lysozymes, related to the chicken-type lysozymes in vertebrates, are ubiquitous components in the bacteriolytic armamentarium of insects. The enzyme is normally present in the blood, and together with other bactericidal factors lysozyme is often strongly induced when the insect is infected. This response is regulated by mechanisms that are related to those that activate inflammatory, acute-phase and immune responses in mammals, and the induction of lysozyme and other factors is now being investigated as a model for innate immune reactions in general. A special adaptation is seen in flies like Musca and Drosophila. These animals live on the microorganisms in decompositing matter, and they have developed a specialized set of lysozymes that are expressed in the alimentary tract. In Drosophila, at least seven different lysozyme genes are clustered in a small region on the third chromosome. The different genes are expressed in different parts of the digestive tract, and at different time points during development, and they are highly divergent in sequence. The major lysozymes in the fly gut have acidic isoelectric points and/or pH optima, and their evolution provides an interesting parallel to the ruminants.
The A.A. Zavarzin's law of parallel lines in tissue evolution showing the appearance of a common tissue organization pattern is the major regularity of the cellular development of animals in phylogenesis. It carries out the metabolism principally similar in all animals in their interaction with the environment. The A.A. Zavarzin's law of parallel lines is also the main regularity of the evolution of tissue interrelations bringing about the principal processes of metabolism. The tissue evolution as well as the evolution of the organism is under the influence of factors of heredity, variability and natural selection. These factors however have an influence mediated by the organism evolution. The precess of cephalization represents a fairly important manifestation of the evolution of animals. The theory of general histogenesis reflects the main regularity of the cellular development in ontogenesis of man and animals. Being a further development of the conception of the A.A. Zavarzin's tissue evolution this theory shows the development of the animal cellular structure as a single general process of histogenesis, beginning with a zigote and continuing till the end of the organism life. The integration, heterochronia and determination manifest themselves in this process of differentiation of cells, tissues and intertissue relations.
Traditionally, evolutionary biologists have viewed mutations within individual genes as the major source of phenotypic variation leading to adaptation through natural selection, and ultimately generating diversity among species. Although such processes must contribute to the initial development of gene functions and their subsequent fine-tuning, changes in genome repertoire, occurring through gene acquisition and deletion, are the major events underlying the emergence and evolution of bacterial pathogens and symbionts. Furthermore, pathogens and symbionts depend on similar mechanisms for interacting with hosts and show parallel trends in genome evolution.
The paper elucidates certain methodological problems of evolutionary histology. The principal attention is given to the necessary synthesis of modern molecular biology and genetics and evolutionary histology. Modern data on the levels of the organization of the living matter and their significance for the rightness of the A.A. Zavarzin's theory of parallel lines in the tissue evolution are presented. The hypothesis of an application of the theory of parallel lines in the hereditary variability by N.I. Vavilov to the analysis of regularities of the tissue evolution is set forth. The hypothesis is proposed that mutation changes of similar genes in representatives of different types of animals underlie the regularities of the tissue evolution discovered by A.A. Zavarzin, and epigenomic changes of regulation systems occurring most frequently in the process of ontogenesis of organisms lie in the basis of the divergent evolution of tissues after N.G. Chlopin.
The genetic differences underlying unique phenotypes in humans compared to our closest primate relatives have long remained a mystery. Similarly, the genetic basis of adaptations between human groups during our expansion across the globe is poorly characterized. Uncovering the downstream phenotypic consequences of these genetic variants has been difficult, as a substantial portion lies in noncoding regions, such as cis-regulatory elements (CREs). Here, we review recent high-throughput approaches to measure the functions of CREs and the impact of variation within them. CRISPR screens can directly perturb CREs in the genome to understand downstream impacts on gene expression and phenotypes, while massively parallel reporter assays can decipher the regulatory impact of sequence variants. Machine learning has begun to be able to predict regulatory function from sequence alone, further scaling our ability to characterize genome function. Applying these tools across diverse phenotypes, model systems, and ancestries is beginning to revolutionize our understanding of noncoding variation underlying human evolution.