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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↗
PubMed1997

[Chronic angina pectoris in the patient with arterial hypertension].

Reference is made to the close relationship between high prevalent arterial hypertension and coronary heart disease, including the vascular risk factor as well as the common genetic and psychosocial factors that influence the development and parallel evolution of vascular and heart diseases. The importance of assessing of the total burden of coronary heart disease risk and its general management is emphasized and some aspects of the treatment of angina pectoris in hypertensive patients are mentioned.

Angina Pectoris↗
PubMed1997

[Hypertension and primary glomerulonephritis in adults. A study of 302 cases].

The purpose of the present work was to show the place of hypertension in primary glomerulonephritis in adults. Hypertension was defined as diastolic blood pressure above 90 mmHg and renal insufficiency as serum creatinine above 135 mc mol/L. Secondary glomerulonephritis was excluded. The study was performed in 302 patients with primary glomerulonephritis biopsied between March 1994 and March 1996. They were 183 males and 119 females, aged from 16 to 63 years (mean: 29.8 years). The incidence of hypertension at the time of admission was 46.6%: 141/302 cases. The only consideration of prolonged hypertension (excluded transient hypertension of acute nephritic syndrome) shows an incidence of 31.4%: 95/302 cases (table). Frequency of hypertension (HT) in different types of primary glomerulonephritis (GN): [table: see text] The histological types observed in these cases of hypertension were represented essentially by the proliferative lesions: 73% (72/95 cases) who were grouped mainly in proliferative glomerulonephritis postinfectious and IgA nephropathy. No proliferative lesions: 24% (23/95 cases) were especially represented by focal segmental sclerosis. Renal insufficiency noted in 69 cases on 95 hypertensions was probably the result of the parallel evolution of hypertension renal lesions and those belonging to these histologic types. In conclusion, this study shows a narrow correlation between the hypertension and proliferative glomerulonephritis in our young adults population.

Adolescent↗
PubMed1997

In search of a bacterial species definition.

The bacterial species concept was examined within the framework of plant and animal associated alpha-2 proteobacteria, taking into consideration the phylogenetic, taxonomic and biological approaches as well as the microbiologists' perception. The virtue of the phylogenetic approach is that it gives an evolutionary perspective of the bacterial lineage; however the methods used possess low resolution for defining species located at the terminal branches of the phylogenetic trees. The merit of the taxonomic approach is that species are defined on the basis of multiple characteristics allowing high resolution at the terminal branches of dendograms; its disadvantage is the inaccuracy in the earlier nodes. On an individual level, the qualitative biological characteristics used for the definition of species frequently reveal shortcomings because many of these properties are the result of coevolution, parallel evolution or the horizontal transfer of genes. Nevertheless, when considered together with the phylogenetic and taxonomic approaches, important uncertainties are discovered: these must be weighed if a practical definition of bacterial species is conceived. The microbiologists' perception is the criterion expressed by a group of sponsors who, based on scientific and practical grounds, propose a new bacterial species. The success of this new proposal is measured by its widespread acceptance and its permanence. A difficult problem concerned with defining bacterial species is how to distinguish if they are independent evolutionary units or if they are reticulate evolutionary units. In the first case the inherence is vertically transmitted as a result of binary fission and clonal expansion. This may be the case of some animal cell associated bacteria in which recombination appears to be precluded or exceptional. In the second case adaptive changes occurring within an individual can be horizontally transferred to many or all group members. This seems to be the condition of many intestinal and plant associated bacteria. Genetic drift and speciation in clonal bacteria will depend almost exclusively on mutation and internal genetic rearrangement processes, whereas speciation in reticulate bacteria will depend not only on these processes but in their genetic interactions with other bacterial strains. This uncertainty, which corresponds to the evolutionary process, is at the same time one of the key factors in defining a bacterial species.

Bartonella↗
PubMed1998

[Prevalence of uro-nephrologic complications of urinary bilharziasis in hyperendemic focus in Madagascar].

This prospective study was designed to look for and describe urologic and nephrologic consequences of urinary bilharziosis due to schistosoma haematobium in a hyperendemic hotbed in the middle west of Madagascar. Methodology included clinical examination, kidney and bladder ultrasonography, urine dipsticks and creatininemia. Amongst a population of 574 persons aged 5 years ore more, 436 (76%) had bilharziosis ova in the urine (filtration method). From the clinical point of view, 257 patients (58.9%) had microscopic hematuria, 178 (40.8%) had presently an hematuria; 111 patients (25.5%) suffered from dysuria; 18 patients (4.1%) had limb oedema when 3 patients had present oedema (0.7%). Among 436 checked people, 267 (61.2%) had an ultrasonography abnormality. In 252, it was bladder wall abnormalities (57.8%). They were wall irregularities in 182 cases (41.7%); vesico-ureteral reflux in 22 cases (5.3%); ureteral dilatations in 22 cases (5.3%) and pyelocalyceal dilatations in 61 cases (13.9%). Prevalence of proteinuria 75.2% (316 amongst 420 checked people) of whom 5.7% (24 cases) had 5 g/l or more. Hematuria was found in 352 patients (83.8%) of whom 238 (56.7%) had more than 250 erythrocytes per microliter. Prevalence of leucocyturia was 56.7% (238 cases). Creatininemia was measured in 140 people with positive filtration; it was normal in all except two patients. This study highlights the parallel evolution between parasitic infection and uronephrological manifestations of the disease.

Adolescent↗
PubMed2026

The Spatial and Temporal Repeatability of Genomic Responses to Natural Selection as Demonstrated in Stickleback Populations Experiencing Highly Dynamic Environments.

The evolution of genotypic parallelism under shared environmental conditions provides strong evidence for the role of natural selection. However, analyses typically examine genomic signatures of selection long after the putative selection event and only assess the repeatability of responses across spatial population replicates. This impedes our ability to attribute a particular response to a given selection pressure and to distinguish non-parallel responses caused by stochastic processes from those caused by local selection. As such, the consistency of natural selection over space and time is unknown, and the role of persistent local selection pressures is unclear. Here, we leveraged the natural bar-built estuary system of Santa Cruz, California, to examine the repeatability of seasonal genomic change in threespine stickleback (Gasterosteus aculeatus) over space and time. By comparing allele-frequency shifts that are shared across locations (spatial repeatability) with those that are shared across years within locations (temporal repeatability), we identified both spatially shared and local components of putative selection. We found that repeated seasonal outlier responses occurred more often than expected under a neutral null model. Although repeatability declined as the number of estuaries sharing an outlier increased, enrichment above neutral expectations increased with broader spatial sharing, particularly for outliers repeated across both years. While the precise outlier SNPs varied across years, estuary-specific patterns of responses were broadly consistent, suggesting an important role for local conditions. Together, our findings show that temporal sampling can reveal components of putative selection that would be missed from spatial comparisons alone. More broadly, they highlight the importance of examining repeatability over both space and time to understand the parallel and non-parallel components of adaptive genomic change.

Animals↗
PubMed1995

Evolution of safety in anesthesia.

The evolution of anesthesia safety has paralleled the evolution of anesthesia over the last several hundred years. This article describes the introduction of safer practices of anesthesia and the impetus for these changes in practice that improved patient safety. It discusses both the role of technology in the advancement of safety and the policies developed by professional organizations of anesthesia care providers.

Anesthesia↗