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PubMedDate not supplied

[Course of inflammatory and nutrition proteins in bacterial infections in newborn infants].

A study of 214 neonates (with 87 premature infants) reveals that C-reactive protein (CRP), orosomucoid and prealbumin are the most interesting proteins for the diagnosis of neonatal sepsis and for studying its follow-up. Orosomucoid is high in 85% of bacterial infections and CRP in 75%. Early type strep B infections give often false negative results. The evolution of CRP and of prealbumin corresponds to the effects of treatment and the evolution of orosomucoid is parallel to the healing of the patients. The ratio orosomucoid/prealbumin allows an earlier appreciation of the healing.

Bacterial Infections↗

PubMedDate not supplied

[Recurrent confusional states and periodic lateralized epileptiform discharges: a new type of non-convulsive status epilepticus?].

Periodic lateralized epileptiform discharges (PLEDs) in an EEG usually indicate the presence of an underlying structural lesion (of vascular origin in most cases). PLEDs are also sometimes observed in certain types of infections (mainly viral), in which they may even constitute a characteristic finding useful for diagnostic purposes. In recent years cases have been reported in which PLEDs are linked to recurring confusional states that do not fit in with established classifications and that may be epileptic in nature. We discuss the cases of 2 patients who were repeatedly admitted to our hospital in confusional states, in whom PLEDs were observed in EEG readings. Clinical evolution in both cases paralleled EEG alterations. We were able to perform both critical and intercritical single proton emission tomography on 1 patient, finding, respectively, hyper- and hypoabsorption foci. Symptoms resolved with antiepileptic treatment.

Aged↗

PubMed1994

[Kienboeck disease: treatment by shortening osteotomy of the radius].

INTRODUCTION: A series of twenty eight cases of Kienbock's disease treated by a shortening osteotomy of the radius are reported. MATERIAL AND METHODS: The series consisted of sixteen male and twelve female patients with an average age of twenty-five and followed for an average of five years. Seventeen patients were manual workers. The dominant side was affected in twenty cases; there were no bilateral cases. The clinical grades before surgery were one case in stage I, ten stage II, thirteen stage III, and four stage IV, using the Decoulx classification. The preoperative distal radio ulnar index was greater than 0 in only one case. Average radial shortening was three millimeters. The osteotomy was stabilized by using dynamic compression plates in fourteen cases, pinning in twelve cases, and staples in two cases. RESULTS: In all the cases, the results on pain relief and muscular strength were satisfactory. During preoperative review, pain was a major complaint in seventeen cases, moderate in nine cases, and slight in two cases. Joint range of motion (ROM) was, in seven cases, greater than seventy-five percent when compared to the opposite hand; in fourteen cases greater than fifty percent; less than fifty percent in five cases and less than twenty-five percent in two cases. Muscular strength, measured by J.A.M.A.R. test, was decreased in six cases by seventy-five percent when compared with the healthy side; in nineteen cases decreased by fifty percent and in three cases decreased by twenty-five percent. On the post-operative review, pain was decreased in all cases: twenty patients were pain free, seven felt slight pain during forced movements. Only one patient showed no improvement: he had a work related injury, with reflex dystrophy. A twelve percent increase in postoperative ROM was noted. Muscular strength improved by an average of forty one percent: 8 cases recovered normal strength, fifteen cases improved strength to seventy-five percent, and five cases improved to fifty percent. The overall clinical result did not seem to depend on the age of the patient or the preoperative radiological stage. They were evaluated using the criteria described by Michon. We obtained fourteen excellent results, ten good, four average. Twenty-five patients have been able to their previous job, three changed jobs. For the preoperative radiological assessment, we followed the Decoulx and the Lichtman scales and considered the distal radio ulnar index, the radial slope, the Linscheid lunate bone dimple incline and the Young and Mac Murtry measurement of the carpal collapse. Radiological assessment showed lunate bone remodeling in the ten cases rated stade II. Nine out of the thirteen patients rated stade III improved: two of them were rated stade II and seven cases presented an improvement of the radiological aspect. Four cases worsened. DISCUSSION: There was no parallel between the radiological evolution of the lunate bone and clinical results. Furthermore, radiological assessment did not show any true relationship between changes in the distal radio ulnar index and radiological evolution. The post-operative distal radio ulnar index was zero in eight cases, greater than one in fourteen cases and greater than two in six cases. Only the obliquity of the radial dimple opposite to the lunate bone is related with the radiological evolution. In the nine cases of stage III that have improved, the radial dimple slope was increased. The four cases of stage III that worsened, it was decreased. CONCLUSION: A shortening osteotomy of the radius is a satisfactory procedure independently of whatever the disease's age, the lunate bone radiological stage and the distal radio ulnar index. The only factor we think capable of modifying the radiological result of necrotic evolution is the lunate bone slope. It appears necessary, during the osteotomy, to increase this slope in order to reduce local pressure.

Adolescent↗

PubMed1996

Clonal evolution of lung tumors.

Lung tumors, particularly squamous cell carcinomas, are believed to develop through a series of morphological abnormalities, driven by underlying somatic genetic changes. One way of studying this process is to analyze candidate somatic genetic changes in samples of squamous metaplasia and bronchial dysplasia of varying degrees of severity as well as tumor from the same patient. This assumes a clonal relationship between these lesions. In this article, we provide evidence that adjacent, physically distinct bronchial abnormalities are clonally related. This has been achieved using a plaque assay technique to detect the same p53 mutation, present throughout a tumor specimen, in a small proportion of cells in an adjacent squamous metaplasia. In addition, we have obtained two dysplasia samples from a tumor-free patient over a 9-month interval. The earlier sample had one p53 mutation, whereas the later sample has to p53 mutations on different alleles. Thus, the pattern of clonal evolution detected in the parallel samples mimics the pattern seen in longitudinal samples and supports the analysis of synchronously collected samples for the study of tumor progression.

Base Sequence↗

PubMedDate not supplied

Evolution of renal function abnormalities in the db/db mouse that parallels the development of human diabetic nephropathy.

The db/db mutant mouse is a rodent model of genetic diabetes that develops renal glomerular lesions with striking mesangial matrix accumulation by the age of 16 weeks, after 8-10 weeks of sustained hyperglycemia. However, abnormalities in renal function that antedate or accompany the appearance of these pathologic changes, which resemble those found in human diabetes, have not been delineated. We therefore examined renal function in young db/ db mice and their nondiabetic db/m littermates from the age of 8 through 15 weeks. Serum creatinine and blood urea nitrogen concentrations at the onset of diabetes in db/db mice did not differ significantly from mean concentrations in db/m controls. An elevated creatinine clearance, due in large part to increased body weight, and increased urinary albumin excretion were observed in db/db compared with db/m mice soon after establishment of sustained hyperglycemia. A relative reduction in creatinine clearance was demonstrable in db/db mice at the age of 15 weeks, coincident with the appearance of overt compromise in renal function manifested by frank increases in the serum creatinine and blood urea nitrogen. The findings indicate that the well-documented glomerular pathology in db/db mice is accompanied by definable alterations in renal function, which are similar in chronology and nature to those found in human diabetes.

Aging↗

PubMed1997

[Automation of the cytometric analysis of the DNA content of solid tumors].

An automatic machine, dedicated to solid tumor DNA ploidy quantitation has been built in order to provide pathologists with a tool usable in clinical practice. Main efforts were focused on an automation of each step of the analysis and on an elimination of any subjective choice, while preserving the quality of measurement. As the software is independent of the machine architecture, it offers performances which increase in parallel with the rapid evolution of the computers. An illustration of the various functionalities of the automaton is proposed through the study of deparaffined breast cancer samples.

Breast Neoplasms↗

PubMed1998

Selection, convergence, and intragenic recombination in HLA diversity.

To account for high degrees of human leukocyte antigen (HLA) diversity, a method is proposed for detecting intragenic recombination or gene conversion separately from parallel substitutions or convergent evolution. An application of the method to HLA protein sequences suggests that intragenic recombination played important roles in HLA-B and DPB1, some in HLA-A and DRB1, and least in HLA-C and DQB1 diversity. However, the extent of diversity of these molecules does not necessarily correlate with the frequency of intragenic recombination, supporting the view that (balancing) selection is a primary agent of HLA diversity and often leads to convergent evolution. Computer simulation is carried out to examine two models of balancing selection under the coupled effect with mutation, intragenic recombination, and random drift in a diploid population. It is emphasized that break points by intragenic recombination need be specified to account for HLA diversity. Implications of HLA diversity in human evolution are briefly discussed.

Amino Acid Sequence↗

PubMed1998

Neurogenically mediated cystitis in rats: an animal model.

PURPOSE: Pseudorabies virus (PRV) is a useful tool for mapping the control circuitry of the spinal cord. In the process of mapping CNS regulatory pathways for the lower urinary tract, a hemorrhagic change in the bladder was observed that was not overtly evident in other pelvic organs. The relationship between the appearance of hemorrhagic changes in the bladder and the evolution of PRV induced changes in the spinal cord was therefore explored. MATERIALS AND METHODS: Sprague-Dawley rats were injected with PRV into the ACD tail-muscle. Bladder and CNS fixation were achieved by transcardial perfusion with formaldehyde. Multi-level sections were obtained from T8 through S4. Fixed tissue was stained and evaluated by light microscopy. Immunohistochemical stains were carried out for PRV and iNOS on spinal cord tissue. We were therefore able to evaluate the relationship between the manifestation of the hemorrhagic cystitis, appearance of the PRV in the spinal cord and evidence of CNS inflammation. RESULTS: The evolution of hemorrhagic cystitis paralleled the evidence of inflammation in the thoraco-lumbar and sacral cord. These bladders contained 5 to 9 ml. of bloody urine (a normal rat bladder contains 1 to 2 ml.). On cystomanometry (CMG) the bladders were acontractile. No PRV could be cultured in the hemorrhagic bladders. The histological changes observed in the bladder represent true inflammation. CONCLUSION: There was no obvious explanation for these changes other than the associated inflammatory changes in the spinal cord. The findings are consistent with the hypothesis that a spinal cord stress, via an unknown metabolic pathway, can result in dramatic, neurogenically mediated changes in the bladder.

Animals↗

PubMed1989

Evolution of immunoglobulin light chains: cDNA clones specifying sandbar shark constant regions.

Sharks are living fossils that are indistinguishable morphologically from their Devonian ancestors of approximately equal to 400 million years ago. If parallel conservatism characterizes their biochemical evolution, characterization of their immunoglobulin chains could provide information regarding the primordial features of these essential defense molecules. Shark immunoglobulins are polydisperse like those of mammals, but these species lack homogeneous myeloma proteins. This heterogeneity has precluded direct determination of the sequence of elasmobranch light-chain proteins. We have sequenced four cDNA clones that contain the constant-region sequence as well as varying degrees of variable- or joining-region segments. The sandbar shark (Carcharhinus plumbeus) has at least four distinct light-chain constant regions, and these can be considered homologs of mammalian lambda chains. Approximately 40% identity was found in comparison from sharks to mammals. Certain stretches of sequence were remarkably conserved, whereas others varied in a manner consistent with accepted concepts of speciation. One hexapeptide (Ala-Thr-Leu-Val-Cys-Leu) occurred in lambda constant regions of all vertebrate species. There was a universal conservation of certain cysteines, phenylalanines, tryptophans, and glycines and strong identities in the block of residues from Ser-176 to Trp-186. Comparison of the shark sequence with that of the characterized human lambda myeloma protein Mcg indicates a strong conservation of three-dimensional structure in this light-chain domain representing species whose ancestors diverged early in vertebrate evolution. The shark light-chain sequence contains primordial features shared by mammalian kappa and lambda chains and by T-cell receptor beta chains.

Amino Acid Sequence↗

PubMed1985

Cross-species gene transfer; implications for a new theory of evolution.

It has been established that genes can be transferred and expressed among procaryotes of different species. I am hypothesizing--and there is mounting evidence for this conclusion--that genes are transferred and expressed among all species, and that such exchange is facilitated by, and can help account for, the existence of the biological unities, from the uniform genetic code to the cross-species similarity of the stages of embryological development. If this idea is correct, the uniformity of the genetic code would allow organisms to decipher and use genes transposed from chromosomes of foreign species, and the shared sequence of embryological development within each phylum would allow the organism to integrate these genes, particularly when the genes affect complex morphological traits. The cross-species gene transfer model could help explain many observations which have puzzled evolutionists, such as rapid bursts in evolution and the widespread occurrence of parallelism in the fossil record.

Animals↗

PubMed1998

Blastic Transformation in a Case of Hairy Cell Leukemia.

Background: Hairy cell leukemia (HCL) is a slowly progressive lymphoproliferative disorder that tends to afflict middle-aged adults, especially men. Blastic transformation of this form of leukemia is extremely rare. To date, a single case has been reported. Methods and Results: A case of HCL, evolving with blastic transformation after a 9- year clinical course, is reported. Routine histology, cytochemistry, flow cytometry immunophenotyping, and Southern blot analysis for B- and T-cell gene rearrangements were used in the evaluation. Although morphology at the time of presentation was characteristic of HCL, the cells were initially tartrate-resistant acid phosphatase (TRAP) negative. During a clinical course over several years, the hairy cells became progressively TRAP positive. The morphology of the leukemic cells changed 9 years after initial diagnosis, with blastic transformation and retaining strong TRAP positivity. Immunophenotypic analysis showed evolution from a characteristic hairy cell leukemic phenotype to a phenotype indicative of marked immaturity. Genotypic analysis showed an evolving pattern of immunoglobulin gene rearrangements, paralleling the morphology and phenotypic evolution and ruling out a second B-cell malignancy. Conclusions: This case report of blastic transformation in a patient with HCL is only the second such case identified in the medical literature to date.

Journal Article↗

PubMed2003

Divergent selection during speciation of Lake Malawi cichlid fishes inferred from parallel radiations in nuptial coloration.

Repeated evolution of the same phenotypic difference during independent episodes of speciation is strong evidence for selection during speciation. More than 1,000 species of cichlids, >10% of the world's freshwater fish species, have arisen within the past million years in Lakes Malawi and Victoria in eastern Africa. Many pairs of closely related sympatric species differ in their nuptial coloration in very similar ways. Nuptial coloration is important in their mate choice, and speciation by sexual selection on genetically or ecologically constrained variation in nuptial coloration had been proposed, which would repeatedly produce similar nuptial types in different populations, a prediction that was difficult to test in the absence of population-level phylogenies. We measured genetic similarity between individuals within and between populations, species, and lake regions by typing 59 individuals at >2,000 polymorphic genetic loci. From these data, we reconstructed, to our knowledge, the first larger species level phylogeny for the most diverse group of Lake Malawi cichlids. We used the genetic and phylogenetic data to test the divergent selection scenario against colonization, character displacement, and hybridization scenarios that could also explain diverse communities. Diversity has arisen by replicated radiations into the same color types, resulting in phenotypically very different, yet closely related, species within and phenotypically highly similar yet unrelated sets of species between regions, which is consistent with divergent selection during speciation and is inconsistent with colonization and character displacement models.

Africa, Eastern↗

PubMed2005

Specific loss of the extrinsic 18 KDa protein from photosystem II upon heating to 47 degrees C causes inactivation of oxygen evolution likely due to Ca release from the Mn-complex.

Exposure of Photosystem II (PS II) membrane particles from spinach to a temperature of 47 degrees C caused the rapid release of the 18 kDa protein in parallel to inactivation of oxygen evolution. Previously, it has been suggested that the first heat-jump response involves rapid Ca release from the Mn complex of O2-evolution, followed by the slower release of (2 + 2) MnII ions [Pospisil P et al. (2003) Biophys J 84: 1370-1386]. Here, the predicted biphasic MnII release to the bulk was verified by atomic absorption spectroscopy (AAS). Analysis of laser flash-induced delayed fluorescence transients suggests that the loss of the essential Ca ion from the Mn4Ca complex in the dark is due to the loss of the 18 kDa protein. The S2-state multiline EPR signal of the Mn complex was still generated in heat-treated PS II presumably lacking Ca, but retaining four Mn ions.

Calcium↗

PubMed1986

[The origin of the eukaryotic cell. III. Principles of the morphofunctional organization of the eukaryotic cell].

The eukaryotic plasmalemma, eukaryotic cytoplasm with its usual cytomembranes, and eukaryotic nucleus are obligatory components of the eukaryotic cell. All other structural elements (organelles) are only derivates of the aforesaid cell components and they may be absent sometimes. There are protozoans having simultaneously no flagelles, mitochondria and chloroplasts (all the representatives of phylum Microspora, amoeba Pelomyxa palustris, and others). The following five general principles play the main role in the morphofunctional organization of the cell. The principle of hierarchy of block organization of living systems. Complex morphofunctional blocks (organelles) specific for the eukaryotic cell are formed. The compartmentalization principle. The main cell organelles (nuclei, flagellae, mitochondria, chloroplasts, etc.) undergo a relative morphological isolation from each other and other cell organelles by means of the total or partial surrounding by membranes; this may ensure the originality of their evolution and function. The principle of poly- and oligomerization of morphofunctional blocks. It permits the cell to enlarge its sizes and to raise the level of integration. The principle of heterochrony, including three subprinciples: conservatism of useful signs; a strong acceleration of evolutionary development of the separate blocks; simplification of the structure, reduction or total disappearance of some blocks. It explains a preservation of prokaryotic signs in the eukaryotic cell or in its organelles. The principle of independent origin of similar morphofunctional blocks in the process of evolution of living systems. The parallelism of the signs in unrelated groups of cells (or protists) arises due to this principle.

Animals↗

PubMed1995

History of brain and epidural metastases from breast cancer in relation with the disease evolution outside the central nervous system.

We reviewed 89 breast cancer patients with brain or epidural metastases in order to see whether a parallelism could be found between disease evolution inside and outside the central nervous system. One-fifth of the patients with brain metastases did not have any other site of relapse before neurological complication. Among the 38 patients who developed brain metastases and had a prior history of relapse outside the brain, 12 had control of constant extracranial sites while disease was progressing at these sites in 26 of them. In the epidural metastases group, all patients but 4 had progressive disease elsewhere when neurological complication appeared.

Adult↗

PubMed1987

Evolution of diuretics and ACE inhibitors, their renal and antihypertensive actions--parallels and contrasts.

The emergence of diuretic drugs and angiotensin converting enzyme (ACE) inhibitors ranks amongst the major therapeutic advances of modern medicine. The discovery of these drug groups arose largely by chance, yet each has dramatically influenced the treatment of congestive cardiac failure and arterial hypertension. The central role which diuretics have had in the management of both oedema and hypertension hinges on their ability to induce a net renal excretion of solute and water by selective interference with either active or passive ion transport processes in different segments of the nephron. Irrespective of sites of action, the continued antihypertensive action of diuretics is characterized by a reduction in plasma volume and extracellular fluid (ECF) volume that lasts for as long as the diuretic is given. The mechanism of this effect remains unclear but may involve autoregulatory reactions that leave cardiac output unaltered but maintain a sustained reduction in total peripheral resistance. ACE inhibitors also lower blood pressure by decreasing total peripheral resistance, leaving cardiac output, plasma volume and ECF volume unchanged. The detailed way these haemodynamic changes are achieved remains unknown but inhibition of converting enzyme present not only in the kidney but also in many extrarenal tissue sites, appears important. In both hypertension and cardiac failure, however, the kidney acts as a key target organ for ACE inhibitors. The increased renal vascular resistance and inappropriate renal salt excretion are reversed with enhanced renal blood flow and saluresis. Both angiotensin II (AII) and vasopressin-mediated contraction of glomerular mesangial cells is inhibited, making glomerular filtration more efficient. Reduced aldosterone secondary to blockade of AII formation contributes to saluresis whilst encouraging positive potassium balance. ACE inhibition also impairs breakdown of kinins which may contribute to intrarenal and peripheral vasodilation either on their own or via release of prostaglandins and other vasoactive substances. The hypotensive actions of diuretics are potentiated by ACE inhibition primarily through blockade of AII formation and prevention of secondary aldosteronism. In combination, these drugs permit low doses to be used because of their synergistic effects. Caution has to be exercised whenever ACE inhibition is used, without and especially with diuretics, in the management of renovascular hypertension and other low-perfusion states. In these circumstances, AII plays an important autoregulatory role in preserving glomerular filtration through an increase in post-glomerular resistance.(ABSTRACT TRUNCATED AT 400 WORDS)

Angiotensin-Converting Enzyme Inhibitors↗

PubMed2000

Evolution of self-reproducing programs in a core propelled by parallel protein execution.

An evolutionary core memory system named SeMar is revised so that the entire action of the core might proceed by parallel execution of Proteins. The Proteins created by the transcription of DNA units work as operators and accomplish the corresponding instructions written in DNA units. In the experiment, it is shown that after inoculation of a man-made self-reproducing creature into the core, its offspring evolve through mutational modifications and the efficiency of the replication rate of DNA increases by the polyploidization of DNA sequences.

Algorithms↗

PubMed2003

The evolution of concepts of vestibular peripheral information processing: toward the dynamic, adaptive, parallel processing macular model.

In a letter to Robert Hooke, written on 5 February, 1675, Isaac Newton wrote "If I have seen further than certain other men it is by standing upon the shoulders of giants." In his context, Newton was referring to the work of Galileo and Kepler, who preceded him. However, every field has its own giants, those men and women who went before us and, often with few tools at their disposal, uncovered the facts that enabled later researchers to advance knowledge in a particular area. This review traces the history of the evolution of views from early giants in the field of vestibular research to modern concepts of vestibular organ organization and function. Emphasis will be placed on the mammalian maculae as peripheral processors of linear accelerations acting on the head. This review shows that early, correct findings were sometimes unfortunately disregarded, impeding later investigations into the structure and function of the vestibular organs. The central themes are that the macular organs are highly complex, dynamic, adaptive, distributed parallel processors of information, and that historical references can help us to understand our own place in advancing knowledge about their complicated structure and functions.

Acoustic Maculae↗