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Generating and manipulating transgenic animals using transposable elements.

Transposable elements, or transposons, have played a significant role in the history of biological research. They have had a major influence on the structure of genomes during evolution, they can cause mutations, and their study led to the concept of so-called "selfish DNA". In addition, transposons have been manipulated as useful gene transfer vectors. While primarily restricted to use in invertebrates, prokaryotes, and plants, it is now clear that transposon technology and biology are just as relevant to the study of vertebrate species. Multiple transposons now have been shown to be active in vertebrates and they can be used for germline transgenesis, somatic cell transgenesis/gene therapy, and random germline insertional mutagenesis. The sophistication of these applications and the number of active elements are likely to increase over the next several years. This review covers the vertebrate-active retrotransposons and transposons that have been well studied and adapted for use as gene transfer agents. General considerations and predictions about the future utility of transposon technology are discussed.

Animals↗

Genetic architecture of the cryptic species complex of Acanthocyclops vernalis (Crustacea: Copepoda). II. Crossbreeding experiments, cytogenetics, and a model of chromosomal evolution.

Collectively, populations of Acanthocyclops vernalis, a species complex of freshwater copepods, are remarkably similar as to morphology and DNA content, despite variability in chromosome number. Reproductive isolation had been reported among some populations, but with each new investigation the species boundaries and factors that may influence them appeared less clear. To clarify the pattern of biological species within this group of populations, we adopted a comprehensive approach and examined patterns of reproductive isolation in populations for which morphology, chromosome number, DNA content, and 18S rDNA sequences are known. In this study we established nine isofemale lines from four sites in Wisconsin and performed 266 crosses. Crosses within and among these lines were used to relate the degree of reproductive isolation to chromosome differences and to construct a model to explain the origin and maintenance of chromosome number variability. Different gametic and somatic chromosome numbers were observed among specimens within some isofemale lines. In a few cases, gametes with different haploid numbers were produced by a single female. Matings within isofemale lines always produced at least some reproductively successful replicate crosses (produced viable, fertile offspring). Crosses between lines from the same site showed reduced success relative to within-line crosses. Crosses between populations from distant sites showed limited genetic compatibility, producing viable, fertile F1 offspring but infertile F2 adults. One cross between lines with different chromosome numbers (one with 2n = 8 and one with 2n = 10) produced fertile viable offspring, which reproduced for at least 60 generations. These hybrids had either eight or nine chromosomes in the third generation of inbreeding, and eight chromosomes after 20 generations. These hybrids also had reduced nuclear DNA contents at the third generation, a level that persisted through the 20th generation. Successful backcrosses between some hybrids and their parental lines further demonstrated the potential for genetic compatibility among forms with different chromosome numbers. We propose a model in which alterations due to Robertsonian fusions, translocations, and/or loss of chromosomal fragments generate heritable variation, only some of which leads to reproductive isolation. Hence, some of the criteria traditionally used to recognize species boundaries in animals (morphology, DNA content, chromosome number) may not apply to this species complex.

Animals↗

Genetic conflict, genomic imprinting and establishment of the epigenotype in relation to growth.

Genomic imprinting is the process that differentially modifies the parental alleles at certain genetic loci in the parental germlines. Such modifications of DNA and chromatin are somatically heritable and cause unequal expression of the parental alleles during subsequent development. In mammals, imprinted genes encode a relatively small number of functionally heterogeneous proteins. Nevertheless, imprinted genes exert important effects, primarily on fetal development, and their deregulation is implicated in a variety of pathologies including sporadic, inherited and induced growth disorders. Imprinted loci show several unusual structural and functional characteristics that may be related to mechanistic aspects of mono-allelic expression or to modes of evolution of imprinted genetic loci. Typically, imprinted genes are clustered in certain genomic regions and have relatively reduced intronic DNA content relative to non-imprinted genes. In addition, their regulatory regions frequently contain a combination of features including tandem repeats associated with differentially methylated CpG islands and overlapping transcription of coding or non-coding RNAs. The evolution of imprinting can be understood as the stable outcome of sexual selection acting differently on the parental alleles of genes that influence parental investment in offspring. Consistent with this explanation, imprinted genes are expressed predominantly during embryonic and postnatal development in mammals and in the developing endosperm of plants, and maternal or paternal expression at imprinted loci is associated with reduced or increased parental investment, respectively. Such selective forces have implications for understanding mechanistic aspects of genome reprogramming in the early mammalian embryo.

Animals↗

[Chronic abdominal pain: a pediatric approach].

To treat chronic abdominal pain in a child is a difficult task either in a therapeutic or diagnostic point of view, by the variety of its several causes, displays and evolution. It is important not only to the clinician lent also to the child's family to try to identify the possible organic and psychic etiologies; in the organic causes there are frequently gastrointestinal and genitourinary reasons, but there are many dysfunctional mechanisms that shall not be forgotten. The author believes is useful, for a better understanding, to apply Levine and Rappaport's model, that indicates four primary intervening forces of the abdominal pain; 1. predisposition, dysfunction or somatic illness; 2. habits and life style; 3. personality and learned behavior's the necessity of a deep comprehension in the relationship between term case, sometimes frustrating.

Abdominal Pain↗

An amphioxus netrin gene is expressed in midline structures during embryonic and larval development.

Members of the netrin gene family have been identified in vertebrates, Drosophila and Caenorhabditis elegans and found to encode secreted molecules involved in axon guidance. Here I use the conserved function of netrins in triploblasts, coupled with the phylogenetic position of amphioxus (the closest living relative of the vertebrates), to investigate the evolution of an axon guidance cue in chordates. A single amphioxus netrin gene was isolated by PCR and cDNA library screening and named AmphiNetrin. The predicted AmphiNetrin protein showed high identity to other netrin family members but differed in that the third of three EGF repeats found in other netrins was absent. Molecular phylogene-tic analysis showed that despite the absent EGF repeat AmphiNetrin is most closely related to the vertebrate netrins. AmphiNetrin expression was identified in embryonic notochord and floor plate, a pattern similar to that of vertebrate netrin-1 expression. AmphiNetrin expression was also identified more widely in the posterior larval brain, and in the anterior extension of the notochord that underlies the anterior of the amphioxus brain. All of these areas of expression are correlated with developing axon trajectories: The floor plate with ventrally projecting somatic motor neurons and Rohde cell projections, the posterior brain with the ventral commissure and primary motor centre and the anterior extension of the notochord with ventrally projecting neurons associated with the median eye. Amphioxus is naturally cyclopaedic and also lacks the ventral brain cells that the induction of which results in the splitting of the vertebrate eye field and, when missing, result in cyclopaedia. These cells normally express netrins required for developing axon tracts in the brain, and the expression of AmphiNetrin in the anterior extension of the notochord underlying the brain may explain how amphioxus is able to maintain ventral guidance cues while lacking these cells.

Amino Acid Sequence↗

Identification and chromosome assignment of 23 genes expressed in meat and dairy cattle.

Hepatic and intestinal expressed sequence tags (ESTs) of lactating German Holstein and Charolais cows were used to identify and map genes potentially involved in the regulation of metabolic processes in cattle. Seventeen ESTs were homologous to human gene sequences and six ESTs identified unknown coding sequences in human genomic DNA clones. A cattle-hamster somatic hybrid cell panel and cattle-hamster 5000 rad whole genome radiation hybrid (WGRH) panel were used to assign the ESTs in the bovine genome. Fifteen of the mapped genes and the six ESTs represent new assignments in the established cattle WGRH5000 map. Calculation of the radiation hybrid (RH) mapping data was performed with the software RHMAPPER. The new loci contribute to the completion of the bovine transcript maps and their comparative assignments increase our knowledge about genome evolution between cattle and human.

Animals↗

[Bipolarity correlated factors in major depression: about 155 Tunisian inpatients].

The distinction between the depressive troubles according to their inclusion in bipolar disorders or in recurrent depressive disorders offers an evident practical interest. In fact, the curative and mainly the preventive treatment of these troubles are different. So it is necessary to identify the predictive factors of bipolar development in case of inaugural depressive episode. In 1983, Akiskal was the first who identified those factors: pharmacological hypomania, puerperal depression, onset at early age (<25 years), presence of psychotic characteristics, hypersomnia and psychomotor inhibition. Through this study, the authors try to compare the epidemiological, clinical and evolution characteristics of major depression in bipolar disorders to recurrent depressive disorders in order to indicate the correlated factors with bipolarity. It is a retrospective and comparative study based on about 155 inpatients for major depressive episode during the period between January 1994 and December 1998. These patients were divided into two groups according the DSM IV criteria: bipolar group (96 patients) and recurrent depressive group (59 patients). Both groups were compared according to socio-demographic data, life events in childhood, personal and family history, clinical and evolution characteristics of the index depressive episode. The predictive factors proposed by Akiskal were systematically examined. It was found out that the following factors were correlated with bipolarity: high rate of separation and divorce (17.7% versus 5.1%; p=0.02), family history of psychiatric disorders (56.3% versus 35.6%; p=0.012) especially bipolar ones (29.2% versus 3.4%; p=0,00008), onset at early age (mean age of onset: 24.8 8.2 years versus 34.1 12.6 years; p=0.000004), number of affective episode significantly more frequent (mean 3.6 versus 2.5; p=0.03), sudden onset of depressive episode (44.8% versus 15.9%; p=0.0003) and presence of psychotic characteristics (69.8% versus 16.7%; p=0.0001) catatonic characteristics (37.3% versus 20.3%; p=0.03), hypersomnia (51% versus 20.3%; p=0.03) and psychomotor inhibition (83.3% versus 42.4%; p=0.00007). Negatively correlated factors of bipolar depression were: somatic comorbidity such as diabetes, hypertension and rhumatismal diseases (12.5% versus 28.8%; p=0.012) and association with dysthymic disorders (2.2% versus 12.1%; p=0.029). No correlation was found between bipolarity and life events in childhood, seasonal character, alcoholic dependence and suicide attempt. Concerning the validity of predictive factors of bipolarity proposed by Akiskal, we found: history of bipolar disorders (Sensibility: 29.2%, specificity: 96.6%, Positive Predictive Value (PPV): 93%), hypersomnia (Sensibility: 51%, specificity: 80%, PPV: 80%), onset before the age of 25 years (Sensibility: 62.5%, specificity: 70%, PPV: 77%), psychomotor inhibition (Sensibility: 83.3%, specificity 58%, PPV: 76%), and psychotic characteristics (Sensibility: 69.8%, specificity: 62.7%, PPV: 75%). In spite of methodological differences, our results tallied with the other studies. We focus on the importance of the bipolar family history criterion, which has the highest PPV, and the limits of psychotic characteristics criterion which has the lowest PPV. This may be explained by the frequency of these characteristics of affective disorders in our cultural context. The association of the hypersomnia and psychomotor inhibition in one criterion in order to increase their diagnostic power. Our study helps us to identify the factors that would predict the bipolar evolution of a depressive episode allowing the use of specific treatment and ensuring the improvement of prognostic.

Adult↗

Familial supernumerary marker chromosome evolution through three generations.

A mosaic chromosome complement, 46,XY/47,XY,+r(15), was detected at prenatal diagnosis. Family studies showed the mother and one of her two children to have a bisatellited supernumerary marker chromosome (SMC) in all lymphocytes examined. The maternal grandfather also showed a bisatellited SMC, but in only 2 per cent of his lymphocytes. NOR, DA/DAPI, and chromosome 15 centromere and short arm-specific probes confirmed the identify of the bisatellited SMC and of ring SMC as derived from chromosome 15. An apparently normal male was born at full term. At age 1 year, the baby continues to have normal growth and development. The bisatellited 15 likely originated by somatic mutation in the grandfather (2 per cent cells), was transmitted unchanged to the daughter and grandson (germline transmission, no mosaicism), and then evolved by excising the satellites and forming a ring SMC in the index case. Progressive changes in the frequency and subsequent changes in the structure of this SMC illustrate the unusual characteristics of chromosome 15.

Adult↗

Genetics of nonmelanoma skin cancer.

Cancer is in essence a genetic disease characterized by genomic instability. Unlike classic genetic syndromes in which a single inherited mutation is often sufficient to determine the perturbed phenotype, most cancers, especially solid tumors, develop after an accumulation of multiple genetic lesions. Inherited mutations that predispose individuals to cancer formation are termed germline, while acquired mutations that contribute to tumor development are designated somatic. Bona fide hereditary cancers account for only a small proportion of all documented cancers. Most tumors result from mutations caused by inherent infidelities in DNA replication, carcinogens, or defects in the DNA reparative apparatus. When mutations occur in critical growth regulatory genes, variations in cellular proliferation and survival contribute to the selection of dominant tumor population(s). Furthermore, these mutations may alter the antigenic properties of the cancerous cell and encourage escape from the host response. Thus, cancer is evolution at the microscopic level.

Carcinoma, Adenoid Cystic↗

Reassessment of immortalization complementation group D.

Previous somatic cell hybridization studies have assigned many human cell lines to one of four complementation groups (A-D) for immortalization. We report here that the A1698DM cell line, which contains selectable markers and has previously been defined as the immortalization group D representative, was derived from T24 cells rather than A1698. A1698DM did not undergo senescence when fused with cell lines assigned to groups A, B, or C. This raises the possibility that this cell line has undergone further evolution and lost multiple putative senescence genes so that it is now unable to complement any, or most, other cell lines for senescence. Cell lines previously assigned to group D may, therefore, be heterogeneous with respect to the genetic changes that resulted in their immortalization. This has important implications for strategies to clone senescence genes based on complementation groups.

Cell Fusion↗

Mapping of 13 horse genes by fluorescence in-situ hybridization (FISH) and somatic cell hybrid analysis.

We report fluorescence in-situ hybridization (FISH) and somatic cell hybrid mapping data for 13 different horse genes (ANP, CD2, CLU, CRISP3, CYP17, FGG, IL1RN, IL10, MMP13, PRM1, PTGS2, TNFA and TP53). Primers for PCR amplification of intronic or untranslated regions were designed from horse-specific DNA or mRNA sequences in GenBank. Two different horse bacterial artificial chromosome (BAC) libraries were screened with PCR for clones containing these 13 Type I loci, nine of which were found in the libraries. BAC clones were used as probes in dual colour FISH to confirm their precise chromosomal origin. The remaining four genes were mapped in a somatic cell hybrid panel. All chromosomal assignments except one were in agreement with human-horse ZOO-FISH data and revealed new and more detailed information on the equine comparative map. CLU was mapped by synteny to ECA2 while human-horse ZOO-FISH data predicted that CLU would be located on ECA9. The assignment of IL1RN permitted analysis of gene order conservation between HSA2 and ECA15, which identified that an event of inversion had occurred during the evolution of these two homologous chromosomes.

Animals↗

Molecular analysis of immunoglobulin genes in multiple myeloma.

The study of immunoglobulin genes in multiple myeloma over the last five years has provided important information regarding biology, ontogenetic location, disease evolution, pathogenic consequences and tumor-specific therapeutic intervention with idiotypic vaccination. Detailed analysis of V(H) genes has revealed clonal relationship between switch variants expressed by the bone marrow plasma cell and myeloma progenitors in the marrow and peripheral blood. V(H) gene usage is biased against V4-34 (encoding antibodies with cold agglutinin specificity; anti-l/i) explaining the absence of autoimmune phenomena in myeloma compared to other B-cell lymphoproliferative disorders. V(H) genes accumulate somatic hypermutations following a distribution compatible with antigen selection, but with no intraclonal heterogeneity. V(L) genes indicate a bias in usage of VkappaI family members and somatic hypermutation, in line with antigen selection, of the expressed Vkappa genes is higher than any other B-cell lymphoid disorder. A complementary imprint of antigen selection as evidenced by somatic hypermutation of either the V(H) or V(L) clonogenic genes has been observed. The absence of ongoing somatic mutations in either V(H) or V(L) genes gives rise to the notion that the cell of origin in myeloma is a post-germinal center memory B-cell. Clinical application of sensitive PCR methods in order to detect clonal immunoglobulin gene rearrangements has made relevant the monitoring and follow-up of minimal residual disease in stem cell autografts and after myeloablative therapy. The fact that surface immunoglobulin V(H) and V(L) sequences constitute unique tumor-specific antigenic determinants has stimulated investigators to devise strategies aiming to generate active specific immunity against the idiotype of malignant B-cells in myeloma by constructing vaccines based on expressed single-chain Fv fragments, DNA plasmids carrying V(H)+V(L) clonogenic genes for naked DNA vaccination, or dendritic cell-based vaccination armed with the tumor-specific idiotype.

B-Lymphocytes↗

Oncology nurses and chronic compounded grief.

Oncology nurses have repeated confrontations with death. To suggest that oncology nurses have emotional needs in response to the demands of caring for cancer patients has not been popular even among the nurses themselves. Indeed, there is little written in the professional literature describing the grief experiences of nurses caring for dying patients. To study the grief of oncology nurses, the Grief Experience Inventory (GEI), a multi-dimensional measure of grief that is sensitive to the longitudinal evolution of the process of bereavement, was selected. In addition, a demographic questionnaire to identify professional, personal, and supportive influences that might affect nurses' grief experiences was developed. Data were collected from June 1991 through May 1992, from a total of 50 professional nurses (termed Stayers and Leavers) on adult oncology units in a comprehensive cancer center and in an urban medical center. The findings indicated that both Stayers and Leavers are above the norms in despair, social isolation, and somatization. Implications for education and practice as well as suggestions for education and practice as well as suggestions for further research are discussed.

Attitude of Health Personnel↗

[Girls are more successful than boys at the university. Gender group differences in models integrating motivational and aggressive components correlated with Test-Anxiety].

It is surprising to note the evolution of success rates in Belgian universities especially in the first Year. Men are less successful than women and the differences are escalating in an alarming way. Dropouts take the same direction and women now represent a majority of the students at the university. In a previous study, we assessed 616 students in the first Year at the university of Liège with Vasev, the English name of which was TASTE, a self report questionnaire constituted of 4 factors: anxiety, self confidence, procrastination and performance value; anxiety particularly concerned somatic expression of students before and during test evaluations; self confidence was a cognitive component close to self efficacy; procrastination was the behavioral component characterizing avoidance when students are confronted with the risk of failure; performance value referred to intrinsic and extrinsic motivations. French validation of TASTE led to an abbreviated version of 50 items (THEE) consisting of 5 factors, the four of TASTE and an additional one, very consistent, at first called depression because of its correlations with this dimension, then called sense of competence on account of its semantic content. Self-competence has been described in the literature of Achievement Motivation and corresponded to expectancy and ability beliefs in performance process which was also relevant to self-efficacy except the particularity of comparison with others, which was not included in the last construct. Self-competence has been considered as an important part of the Worry component of test anxiety. Some Authors didn't hesitate to view causality flowing from self-competence to test anxiety and have conceptualized the latter as a failure of the self where one's sense of competence has been undermined as a result of experienced failure. In our study, only that factor was equally scored in women and men whereas it was scored higher in failed students. In other respects anxiety and performance value were scored higher in women, self-confidence and procrastination higher in men. Because TASTE didn't discriminate the different components of motivation (performance value referred to intrinsic and extrinsic motivations without precise distinction) we decided to use the MPS (Multidimensional Perfectionism Scale) which gave the opportunity to distinguish SOP (Self Oriented Perfectionism) ie, the self-imposed unrealistic standards with inability to accept faults in order to know and master a subject, that corresponded to intrinsic motivation; SPP (Socially Prescribed Perfectionism) ie, the exaggerated expectancies of others which are subjectively believed as imposed and uncontrollable leading to anxiety, feelings of failure or helplessness, that corresponded to extrinsic motivation; POO (Perfectionism Oriented to Others) ie, the unrealistic demands expected from significant others, which especially characterized males. We assumed that women attached more importance to succeed and submitted more to society exigencies. That way extrinsic and intrinsic motivations were probably more combined unlike men who, dreading a loss of self esteem, tried to avoid failure responsibility in using self handicapping or aggressive behaviours, so separating motivation in an extrinsic part turned to performance value and an intrinsic one more concerned by self confidence and sense of competence with the result that the motivational balance was surely disrupted in case of high competition leading to failure or avoidance. In another previous study we established a structural model illustrating, according to gender, correlations between anxiety, sense of incompetence, self-oriented perfectionism and socially prescribed perfectionism. Self-oriented perfectionism was less correlated to socially prescribed perfectionism in boys than in girls; furthermore especially by those who had never failed, it was negatively correlated to sense of incompetence, thus leading to lower scores of anxiety while in girls, by contrast, such a correlation didn't exist, thus involving higher anxiety. That way, on the one hand, intrinsic and extrinsic motivations by female students complementarily operated on the sense of incompetence and consequently on anxiety, the emotional component of test anxiety; on the other hand, by male students, intrinsic motivation had a negative correlation with the sense of incompetence and a lower correlation with extrinsic motivation, thereby shedding some light on the problem of anxiety level differences according to gender. More, that observation corresponded well to the model of self-worth where test anxiety was understood as a manifestation of perceived incompetence and as a defensive way to ward off negative self-evaluation; that model suited particularly well to boys and explained their attempts to maintain self-worth when risking academic failure. The present research assumes that independence or combination of motivation components is also correlated to different expressions of aggressiveness: hostility corresponding to threat and characterizing more girls while physical aggression is corresponding to personal challenge, a more masculine attribution. If fighting against the sense of incompetence actually characterizes men and consequently shows too the competitive aspects of performance strong enough to mobilize intrinsic motivation, what would be expected regarding the notion of threat suspected to be predominant in girls? The idea of using a questionnaire discriminating the specific dimensions of aggressiveness in fact the Aggression Questionnaire should meet the following purposes: At first establish a French version of that aggression questionnaire, perform the factorial analyses and internal consistency, compare them with other previous samples, then differentiate gender in general and in failure versus success situations. Finally include the different components of aggressiveness in the first described model and build a new one liable to define in boys the explicit pathways between test anxiety, perfectionism and aggressiveness. Statistical analyses have confirmed, in a 3 factor solution, the presence of emotional (anger), cognitive (hostility) and behavioural (physical aggression) components. Internal consistency is satisfactory. It is demonstrated that physical aggression characterizes boys (F=12.04, p=0.0001) while hostility (F=5.22, p=0.0015) and anger (F=0.49, p=0.0001) characterizes girls; furthermore it is noted that physical aggression characterizes more failed students (F=13.43, p=0.0003). Four models (see figures 2, 3, 4, 5) have been established, at first focused on the distinction of correlations between motivation and cognitive and emotional components on the samples of boys (n=268) and girls (348), then developed on the samples of successful students, male (n=193) and female (n=271). They describe the differentiated action of intrinsic and extrinsic motivations on the different components of aggressiveness and test-anxiety according to gender and without experience of failure. The dynamic process of the organizational factors is different according to gender and psychopathology resulting from the combinations of behaviors, cognitions and emotions would be assumed, prioritizing physical aggression and psychopathy by boys, anxiety and depression by girls. Anyway more explanation about the evolution of success rates of boys and girls in Belgian universities is proposed.

Adult↗

Sequence diversity and chromosomal distribution of "young" Alu repeats.

Members of the recently inserted human-specific (HS)/predicted variant (PV) subfamily of Alu elements were sequenced. A number of these Alu elements share greater than 98% sequence identity with the subfamily consensus sequence, and they are flanked by perfect 5' and 3' direct repeats ranging in size from 6 to 15 nucleotides (nt). Based on the low number of random mutations, the estimated average age of these elements was calculated to be 1.5 million years (Myr). All the young Alu subfamily members were restricted to the human genome, as judged by polymerase chain reaction (PCR) amplification of human and non-human primate DNA samples using the unique flanking sequences specific for each Alu element. The chromosomal locations of several Alu elements belonging to the young subfamilies, designated as HS/PV and Sb2, were determined by PCR amplification of DNA samples from human/rodent somatic cell hybrid panels. A statistical analysis of the chromosomal distribution pattern showed that the recently inserted Alu elements appear to integrate randomly in the human genome.

Animals↗

Germins and germin like proteins: an overview.

Molecular investigations during wheat germination have revealed unique developmentally regulated proteins, designated as germins, which show remarkable resistance to broad specificity proteases and to dissociation in SDS. Germins in cereals have an oxalate oxidase activity, which generates H2O2 from the oxidative breakdown of oxalate thereby playing a significant role in plant development and defense. Germin like proteins (GLPs) exhibit sequence and structural similarity with the cereal germins but mostly lack oxalate oxidase activity. Germins and germin like proteins (GLPs) are a class of developmentally regulated glycoproteins characterized by a beta-barrel core structure, a signal peptide, and are associated with the cell wall. GLPs exhibit a broad range of diversity in their occurrence and activity in organisms ranging from myxomycetes, bryophytes, pteridophytes, gymnosperms and angiosperms. Germins and GLPs are thought to play a significant role during zygotic and somatic embryogenesis (wheat and Pinus, respectively), salt stress (barley and Mesembryanthemum crystallinum), pathogen elicitation (wheat and barley), and heavy metal stress, etc. Characterization and cloning of some of the genes encoding germins and GLPs has facilitated a better understanding of their regulation and raised their potential of biotechnological application.

Biological Evolution↗

[Sensory neuropathy and primary biliary cirrhosis].

Primary biliary cirrhosis (PBC) may associate an axonal neuropathy, a somatic and autonomic neuropathy and a very infrequently sensory neuropathy (with or without xanthomata). The aim of this paper is to describe the case of a 46 year old man diagnosed with PBC in stage I-II and a progressive sensory neuropathy (axonopathy) confined to his upper limbs with distal predominance. It had progressed slowly an began asymmetrically. A complete clinical study excluded other causes of neuropathy. We followed him clinically and electromyographically and he remains stable after two years evolution. The sensory neuropathy in this case, a primary biliary cirrhosis, is compatible with an assymetric sensory neuropathy limited to the upper limbs with assymmetric beginning.

Electromyography↗

Genealogical memory to perinatal iodine-131 exposure in rats: I. Alteration in natural immunity.

A heritable alteration in the natural immunity as measured by changes in the natural killer (NK) cell activities of peripheral blood lymphoid-cells was found to occur in rats upon an in utero exposure to iodine-131. The model that was employed for the measurements consisted of Fischer F344 inbred rats exposed to iodine-131 (sodium) during their 16th to 18th day of gestation. The natural immunity of the animals was evaluated by determining the NK cell activities of peripheral blood lymphoid cells of the offsprings when they reached 2 months of age. Immediately following determination of the natural immunity, brother and sister matings were carried out for evolution of the families. Study of these pedigrees revealed an impairment in the natural immunity to persist through two generations (F1, and F2) of the male animals. The hematological profiles of the animals suggest that the insult may alter the numbers of red and white blood cells in the succeeding generations, but has little noticeable effect upon the percentage of lymphocytes. The interpretation of the results indicate that a perinatal insult by iodine-131 during late gestation can result in both somatic and germ cell changes in the immunological system. Thus, there appears to be a genealogical memory to an in utero radionuclide insult which may adversely affect the offspring's immunological competency to respond to subsequent insults.

Animals↗