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At least 127 records · Page 7Linked to original sources
PubMed1987

Long lasting IgG subclass and antibacterial polysaccharide antibody deficiency after allogeneic bone marrow transplantation.

Serum IgG subclasses were measured by a competitive indirect immunoassay with monoclonal antibodies in 31 leukemic patients before and after bone marrow transplantation. Antibodies to Hemophilus influenzae type b (Hib) capsular polysaccharide were determined in 28 cases. Abnormally low or borderline subclass (mostly IgG2 and IgG4) levels were found late after transplant in 23 infected and noninfected patients. These levels persisted for as long as 25 months, in association with low or borderline IgA levels in 78% of the cases. IgG2, IgG4, and IgA often showed a parallel evolution, whereas IgG1, IgG3, and IgM often varied together in the opposite way. Class but not subclass deficiencies were more frequent in patients with graft-v-host disease (GVHD). Subclass abnormalities predominated in infected patients, with mean levels correlating with the severity of infections; however, the abnormalities are not clearly predictive of infections in individual cases. Most patients with Hib pneumonia showed virtually no IgG antibody response to Hib, and one-half of the patients had a moderate IgM and IgA response. In the whole series, many sera collected greater than 1 year after graft contained very low or undetectable antibodies. Correlation between anti-Hib antibody and IgG2 levels was significant but weak because of discrepancies that were only partially explained by the subclass distribution of the antibodies.

Antibodies, Bacterial↗
PubMed1985

Comparative scanning electron microscopy of the ventricular surface in four actinopterygian fishes: Acipenser ruthenus, Salmo gairdneri, Tinca tinca and Blennius sanquinolentus (Pisces).

The ventricular surface structure of the brains of actinopterygian fishes representing four distinct evolutionary levels was investigated by scanning electron microscopy (SEM). In the chondrostean Acipenser ruthenus ventricular spaces are wide and the ependymal surface is for the greater part densely covered with cilia; apart from macrophages supraependymal cells (SE) are very scarce. In the teleosts Salmo gairdneri, Tinca tinca and Blennius sanquinolentus the ventricles are slit-like, the densely ciliated areas decrease in size. The following regions carry a variety of supraependymal (SE) cells and fibres: the rostral recessus supraopticus, the hypothalamic walls, especially the infundibulum and the dorsal walls of the rhombencephalic ventricle. There is no tight correlation between areas devoid of cilia and the circumventricular organs in teleosts. The long evolutionary history, independent of other vertebrate lines has caused a series of peculiarities in the brain of actinopterygian fishes, including a peculiar ventricular topography. Observations indicate that the rich spectrum of SE cells found in teleosts reflects a parallel evolution rather than a common heredity of teleostean fishes and higher vertebrates.

Animals↗
PubMed1977

[Correlation between inhibition of stimulatory membrane repolarization and positive inotropic response caused by ouabain in rat heart].

During a stimulus train, the diastolic membrane potential of rat atria exhibits a depolarization phase followed by a slower repolarization phase which has been attributed to the activation of an electrogenic sodium pump (ATPase Na+, K+). This pump seems to be all the more active as stimulation frequency is higher. The parallel evolution of the sodium pump inhibition and a positive inotropic effect in response to ouabain perfusion, suggests that the enzymatic inhibition is directly involved in the development of the cardiotonic effect of digitalis.

Animals↗
PubMed1977

[Vogt-Koyanagi-Harada disease. About two observations (author's transl)].

After a reminder of clinical symptoms and development of the V.-K.-H. disease, some histological and clinical observations are related. The clinical observations are very characteristic of the V.-K.-H. disease. There are only two notable points: in both observations, a very low lymphocytic reaction to phytohemaglutinin and in the first observation, the presence of an anemia with parallel evolution to the uveitis. The histological examination of the depigmented area shows an infiltrate as described by Perrot, around the involved area in vitiligo. Ultrastructural study identifies 250 angströms wide particles that appear to be particles of alpha-glycogene, well developed amyelinic endings, and lastly, lymphocytoid cells closely joined with dendritic cells having internal granulations. These aspects have already been found in the iris by the Japanese authors, and they evoked an immunological mechanism.

Adult↗
PubMed1984

[Classification and pathogenesis of cutaneous paraneoplastic syndromes].

The associations between skin conditions and malignant tumours are reviewed and classified in two groups: indirect associations (predisposing genetic factor or carcinogenic agent), and direct associations with parallel evolutions corresponding to the true paraneoplastic syndromes. Occasional associations are also mentioned. The cutaneous paraneoplastic syndromes can be classified according to their pathogenic mechanisms, although these are mostly hypothetical, allowing those of secretory, immunological, deficient and neurovascular origins to be distinguished.

Acanthosis Nigricans↗
PubMed1983

Release of a lymphokine-like plasminogen activator by stimulated B lymphocytes.

This report extends to the guinea pig the discovery of a lymphocyte plasminogen activator (LPA) previously described in the mouse. In the guinea pig, we have identified enzymatic activity similar to that in the mouse, but which has two distinct components: first, as in the mouse, a membrane-bound molecule present even in the quiescent lymphocyte (mLPA), and second, a previously unreported soluble molecule appearing in the culture medium after appropriate cell stimulation (sLPA). This sLPA, like most known lymphokines, was released by in vitro recall of sensitized lymphocytes by the antigen and by direct contact with a mitogen. There was a parallel evolution in the culture for sLPA and for some other well-known lymphokines (LT, LIF), and their detection thresholds were of the same order. A possible activation of plasminogen (Pg) by macrophages contaminating the lymphocyte cultures was carefully rule out. sLPA was produced by lymph node lymphocytes as well as by blood lymphocytes, but not by spleen cells, thymocytes, or peritoneal lymphocytes. A study of the kinetics of the release of sLPA, together with that of metabolic modifiers, suggested that an intracellular synthesis precedes the secretion of the molecule. Data obtained from the use of B- and T-enriched subpopulations or B- or T-dependent antigens and mitogens point to the B lymphocytes as the major, if not exclusive, source of sLPA. The choice of synthetic chromogenic substrates S 2251, S 2444, and S 2288 in some experiments led us to confirm most of the above properties of sLPA with still greater precision and reliability.

Animals↗
PubMed1982

[Alteration of cartilage by microbial agents and granulocytes].

Severe polyarthritis was induced in 42 SPF piglets by subcutaneous and intraarticular infection in one joint of the bacterium Erysipelothrix rhusiopathiae (Serotype B, strain T 28), which in its chronic stage morphologically resembles human c.P. The light and electron microscopic examination of the articular cartilage and synovial membrane reveals a parallel evolution of hyaline cartilage degeneration, and activation and proliferation of synovial lining cells. The initial cartilage alteration with demasking of collagen fibrils and focal degeneration of chondrocytes in the erysipelas model is caused by direct action of the microbial agent, fibrin and few granulocytes Erysipelothrix bacteria and neutrophilic granulocytes are able to invade the superficial and intermediate cartilage layers. This model is not considered a suppurative infectious arthritis. In chronic villous erysipelas polyarthritis, which develops without the presence of neutrophils in the cartilage, the invasively growing synovial pannus dominates, which deeply destroys the pre-damaged cartilage, resulting in macroscopic focal or wide-spread cartilage erosion. We consider the poorly vascularized cartilage and the particular fibrosis suitable sites for the extremely long (up to three years) persistence of this microbial agent. The persistence of the agent is considered necessary for the persisting immunological reactions and the perpetuation of erysipelas polyarthritis. With longer duration (1-3 years) of experimental erysipelas polyarthritis the number of bacteriologically positive arthritic joint decreases. Microscopically, the causative bacteria may only sporadically identified.

Animals↗
PubMed1982

[Destructive arthritis and Behçet's syndrome].

The arthritis of Behçet's syndrome is not usually responsible for articular destructions, so that the presence of destructive lesions makes the diagnosis of Behçet's syndrome doubtful. Here is presented the observation of a 29 years old man (his illness beginning at twelve), with a typical Behçet's syndrome, who developed a destructive arthritis. Arthritic and systemic flares showed a parallel evolution. Destructive lesions involved wrists, hands, feet and elbows. The search for another cause of destructive arthritis (mainly juvenile rheumatoid arthritis and ankylosing spondylitis) was negative. The occurrence of destructive arthropathies in Behçet's syndrome has been exceptionally reported.

Adolescent↗
PubMed1978

[Ontogenic development of the surface of craniofacial sagittal angular sectors in man and chimpanzee].

By means of a technique for measuring surfaces by direct reading, six angular sectors have been studied (3 for the face and 3 for the skull) at various ontogenic periods of Man, common chimpanzee and dwarf chimpanzee. The growth curves have been drawn for absolute values and for relative values. They show a certain evolutive parallelism between the frontal bone and the parietal bone, and between the face and the mandible, with a special fate for the occipital bone.

Adult↗
PubMed1995

[Interaction between anti-infective agents and phagocytes].

Metchnikoff was one of the first to suggest the need for cooperation between phagocytes and therapeutic agents for the benefit of health. After the hopes raised by the discovery and the tremendous development of antimicrobials, there is now a creeping pessimism faced with the parallel evolution of resistance strategies in the microbial world. Interest has now turned to the use of immunomodulatory drugs, alone or combined with anti-infectious agents. Another tendency is based on the possibility that antimicrobials directly interfere with the host-microbe interplay. This review is aimed at summarizing our knowledge of the interactions between antimicrobial agents and the phagocyte, still a cornerstone in the natural defence system. Despite the problems inherent in the analysis and clinical relevance of effects observed in the test tube this developing area of research could provide new therapeutic solutions beyond the year 2000.

Anti-Infective Agents↗
PubMedDate not supplied

Determination of serum myoglobin by the reverse passive hemagglutination assay (RPHA) and radioimmunoassay (RIA).

Serum myoglobin (Mb) is an important biological marker in the early diagnosis of the acute myocardial infarction (AMI). In a previous paper we showed that RPHA, which consists in the agglutination of anti-Mb antibody--coated erythrocytes by solutions containing Mb, is a simple, rapid and highly sensitive assay (approx. 1 ng/ml). 42 sera from AMI patients and 20 sera from healthy subjects were investigated by RPHA. The geometric mean (x/divided by SD) of serum Mb titers in AMI patients was 362 x/divided by 3.94, in the range of 64-8192 (the reciprocal dilutions) and in normal sera was 19 x/divided by 1.36, in the range of 16-32. The difference between the mean values was statistically significant at p < 0.001. Subsequently, serum Mb concentration was determined by RPHA and RIA in 51 AMI sera prelevated at various stages of the disease. A high degree of correlation was found between the two methods. Log Y (RPHA titers) = -0.9174 + 1.5879 log X (RIA); ESE: +/- 0.1947; r = 0.9601. In four AMI patients successive determinations were made at every 6 hours: serum Mb curves determined by RPHA and RIA had a parallel evolution and this was an additional argument for the validation of RPHA. Being quite simple and easy of execution RPHA is the most suitable method by which an early AMI diagnosis can be made.

Blood Donors↗
PubMed1994

Is body mass index sensitively related to socio-economic status and to economic adjustment? A case study from the Congo.

Several nutritional surveys based on representative samples from various urban and rural situations show that the Congo presents a situation of nutritional transition. There is a large prevalence of low body mass index (BMI) in adults from rural zones and this increases with age. There is, however, a large prevalence of high BMI in urban populations despite the persistence of some degree of chronic energy deficiency (CED), particularly at younger ages. Correspondence analysis and logistic regression were used to construct a socio-economic index and measure adjusted risk factors for CED. In rural areas, the major risk factors were old age, sex (women) and the absence of schooling; low economic status, a commonly shared factor, did not differentiate between households for CED. In Brazzaville, CED was linked to a young age (< 30 years) and, clearly, to poverty. The change in the prevalence of CED in mothers from the capital city during a period of economic adjustment showed an increased incidence in young mothers, and also showed that the disparity between low and high economic levels regarding CED had grown. Finally, there was a high level of correspondence between the mean values for the weight-for-height of children and the BMI categories of the mothers. There is a parallel evolution during the period of economic adjustment between the increase of wasting in infants and the increase of CED in mothers. Therefore BMI appears to be a potential core indicator for use in nutritional surveillance in the Congo.

Adolescent↗
PubMed1994

[International harmonization of regular requirements for the registration of drugs: necessity, frena limitations].

Considering the necessity of internationalisation, the Pharmaceutical Industry fears the regulatory variations that may result from national evolutions, parallel or divergent, which sometimes impose on it some repeated works, hence causing an undesirable extension of development duration and also higher costs. Therefore it is quite evident to that Industry that a worldwide harmonization is necessary. For the whole collectivity, such an harmonization allows a better utilization of manpower, of animal experimentation, and also of the material means available for the new pharmaceutical products development. The strong interest showed by the Pharmaceutical industry in France for the International regulatory harmonization, confirms that this Profession has effectively taken into account the worldwide dimension for the medicinal products of the year 2000.

Humans↗
PubMedDate not supplied

[Closing volume and inhomogeneity of the ventilatory mechanical system (author's transl)].

The use of the closing volume (VF) to detect small airway lesions is based on physiological data : it would reflect a special and physiological distribution of the pulmonary inhomogeneity. The aim of this work is to discuss the closing volume as used to determine a pathological process or, in other words, the relationship between the observed profile of closing volume and other functional parameters, whose abnormalities are likely to reflect the inhomogeneity of the ventilatory mechanical system. In 126 patients, who represent a wide range of pathological processes, the authors calculated the closing volume and the following functional parameters : the VC/theoretical VC ratio, the RV measured by dilution method and by plethysmography, the FEV1.0/VC ratio, the expiratory total pulmonary resistance (RPTE), the efficient resistance (R), the airway resistance (Raw), the effective compliance (Ce) measured at the spontaneous respiratory frequency, and its variation in relation with respiratory frequency (f), and a distribution index of inspired gas. After discussion of the procedure and of the reproducibility of the closing volume measurements, the authors recall the significant of the lack of phase IV during the closing volume estimation and expose the reasons which allow to think that closing volume extent and inhomogeneity of the ventilatory mechanics have a parallel evolution. The increase in distribution inhomogeneity of the pulmonary time constants (shown by the slope of the Ce variation in relation with f and gas distribution index) is concomitant with an increase in closing volume. The results show that although the lack of phase IV does not have a univocal signification (and this is a limit to the utilization of the closing volume alone as a detection test) the quantification of the closing volume brings, as the Ce, f relation does, an original element, but the evaluation of Ce, f is more difficult to realize in practice.

Humans↗
PubMed1994

Twenty years medical informatics education at Heidelberg/Heilbronn: evolution of a specialized curriculum for medical informatics.

The medical informatics curriculum at University of Heidelberg/School of Technology Heilbronn started in 1972 as a specialized university curriculum. In this paper, we report on 20 years of experience and the evolution of this educational approach with respect to structure and content of the curriculum. We emphasize that this evolution parallels the development of medical informatics to a medical discipline in its own right, with distinct application domains and specific methodological approaches. Based on our experience and on recommendations from the national and international community, we describe and discuss the features of the curriculum.

Curriculum↗
PubMed1994

School nursing.

School nursing has been in a process of transition since its inception. This role evolution parallels the growing complexity of the health, education, and social needs of America's youth. The workplace within which school nurses practice is equally complicated because health and education administrators often hold differing philosophies of management, and school health programs are ill-defined. Fortunately, there is growing support for an integrated services approach and the development of school health systems with nurses joining an interdisciplinary team rather than continuing to function as "boundary dwellers." The roles of the school nurse as primary care provider, school health coordinator, case manager, and epidemiologist are emerging and replacing outdated nursing functions. As the role of the school nurse shifts and expands, it produces a cascade effect. The role of the school health assistant to aid the nurse surfaces as the next logical step in planning. Numerous model school health programs exist today. The emphasis, and rightfully so, is preventive in nature and should be targeted at the preparation of a new generation of health consumers who are more self-reliant than their predecessors. Unfortunately, all these programs are plagued with financing problems that could be alleviated with the right plan for health care reform, such as an expansion of maternal and child health funds (Title V) to health departments and the introduction of school nursing leadership into the DASH office at the Centers for Disease Control and Prevention, a health education unit largely run by health educators, to reallocate some of these resources to the clinical preventive services needed in schools to reduce health risk behaviors. Finally, total quality management is the next issue on the horizon for this nursing specialty; benchmarking would be the place to start. In summary, systems development in the school health field is now underway, and it will not be easy, but this sort of work never has been simply. It must be remembered that there is nothing more difficult to plan, more doubtful of success, nor more dangerous to manage than the creation of a new system. For the initiator has the enmity of all who would profit by the preservation of the old institution and merely lukewarm defenders of those who would gain by the new ones.

Delivery of Health Care↗
PubMed1995

Biological perspectives on circadian cancer therapy.

Temporal coordination of biologic processes with an approximately 24-hour cycle (circadian) is ubiquitous throughout the animal and plant kingdoms. In each organism studied, the capability to keep biologic time is an inherited characteristic. These biological clocks anticipate, get the organism ready for, regular environmental changes. The immense selective environmental pressure to keep time accurately is reflected in the parallel evolution of different molecular strategies for biologic timekeeping that have apparently arisen independently several times throughout evolution. The anatomic, biochemical, and molecular mechanisms of the clock are currently being defined. Circadian temporal organization at the cellular, organ, and organismic levels results in predictable differences in the capacity of plants, animals, and human beings to respond to therapeutic interventions administered at different times throughout this daily cycle. The biologic basis for these time-of-day differences in therapeutic outcome derive from the circadian dependence of drug pharmacology and the circadian physiology of both normal and malignant tissues. In the treatment of cancer, circadian timing of anticancer drugs, radiation therapy, and biologic agents can result in improved toxicity profiles, enhanced tumor control, and improved host survival. The routine clinical application of such principles is facilitated by the availability of programmable drug delivery devices.

Antineoplastic Agents↗