Molecular characterization of a retrotransposon in Drosophila melanogaster, nomad, and its relationship to other retrovirus-like mobile elements

During a 18-year-period 93 patients (f = 76, m = 17) with a factitious disorder were identified in the psychiatric consultation service of a university hospital (incidence: 0.62%). 50% of women were working in medical professions whereas only 6% of men. Chronic courses of illness were prevailing, but at least one quarter of female patients showed an intermittent type. There was a classical Munchhausen syndrome in 11% of patients. Depressive and anxiety disorders (10%, 4%) were to be respected as psychiatric comorbidity. Ca 25% of the patients suffered from a somatic illness in addition to the factitious disorder, and one third of the women had symptoms of psychosomatic, especially of eating disorders. Previous somatoform disorders, deliberate self harm and attempts of suicide were to be noted in the psychiatric history of many patients. There were frequent traumatizing events (foster home, disturbing family disharmony, physical and sexual abuse, early losses, serious illnesses) in the early biography. Various psychosocial stressors could be identified in the actual eliciting situation. The results are discussed in respect of epidemiology, development and clinical phenomenology of factitious disorders, psychodynamics and psychopathology of deception and self harm, and therapeutic options in the psychiatric consultation service.     

The mutator form of polymerase beta with amino acid substitution at tyrosine 265 in the hinge region displays an increase in both base substitution and frame shift errors

This study describes the first complete in vitro error specificity analysis of a mutator DNA polymerase that is altered in a residue not predicted to contact either the DNA or dNTP substrate. We examined this mutator form of polymerase beta (Y265C) in order to elucidate the critical role tyrosine 265 plays in the accuracy of DNA synthesis. Our results demonstrate that an increase in both frame shift errors in homonucleotide repeat sequences and base substitution errors contribute nearly equally to the Y265C mutator phenotype. The models described for production of these errors, primer/template misalignment and base misincorporation, respectively, are distinctly different, suggesting the Y265C alteration affects discrimination against both types of error production pathways. In addition, Y265C displays a 530-fold increase in multiple errors within the 203-base pair target region examined, relative to that of wild type. Processivity studies revealed that Y265C retains the near distributive nature of DNA synthesis characteristic of the wild type polymerase beta. Therefore, multiple errors exhibited by Y265C most likely result from independent polymerase binding events. Localization of tyrosine 265 in the X-ray crystallographic structure suggests this residue may play a role in mediating a conformational change of the polymerase [Pelletier, H., et al. (1996) Biochemistry 35, 12742-12761]. A conformational change is predicted to enhance the accuracy of DNA synthesis by imposing an induced fit selection against premutational intermediates. The observed loss of discrimination against both misalignment-mediated and misincorporation-mediated errors produced by polymerase Y265C is consistent with such a model.     

The plasmacytoma resistance gene, Pctr2, delays the onset of tumorigenesis and resides in the telomeric region of chromosome 4

Mouse plasmacytomas share pathogenetic features in common with both multiple myeloma and Burkitt's lymphoma in humans. Susceptibility to plasmacytoma induction by intraperitoneal pristane in mice is controlled by multiple genes. At least two of these genes reside on mouse chromosome 4 in regions of the genome sharing linkage homology with human chromosomes 9p21, 1p32, and 1p36. A series of congenic strains recombinant for regions of mouse chromosome 4 in the vicinity of the Pctr2 predisposition locus were created and typed for their tumor susceptibility/resistance phenotypes. These strains were derived by introgressively backcrossing alleles from resistant DBA/2 mice onto the susceptible BALB/cAnPt background. Six resistant and two susceptible strains were allelotyped for 10 genes and 49 random DNA markers to identify the smallest region of overlap in the resistant strains. These studies have determined that the Pctr2 locus resides in either a 500-kb interval proximal to Nppa, or in a 1- to 2-centiMorgan (cM) interval distal to Nppa. In these congenic strain analyses, the Nppa and Fv1 loci, in addition to genes within about 1 cM of these loci, have been excluded as candidates for the Pctr2 locus. A relevant locus that may reside in this interval is Rep2; it is associated with the efficiency of repairing X-ray induced DNA damage sustained during the G2 phase of the mitotic cycle. The Pctr2 locus acts in a codominant fashion. F1 hybrids between resistant and susceptible congenic strains exhibit a reduced tumor incidence and a significant delay in the onset of tumorigenesis. Identification and eventual cloning of the Pctr2 locus may assist in the identification of genes involved in many types of cancer showing aberrations in human chromosome 1p36.     

The open reading frame 1 of the L1Tc retrotransposon of Trypanosoma cruzi codes for a protein with apurinic-apyrimidinic nuclease activity

The deduced amino acid sequence of the open reading frame 1 (ORF1) of the L1Tc non-site-specific non-long terminal repeat retrotransposon of Trypanosoma cruzi exhibits a significant homology with the consensus sequence of the class II family of the endonuclease apurinic-apyrimidinic (AP) proteins. The analysis of the activity of the 40-kDa recombinant protein, named NL1Tc, obtained from the expression of the L1Tc ORF1 in an Escherichia coli "in vitro" expression system revealed that the sequence codes for a protein with endonuclease activity specific for apurinic-apyrimidinic (AP) sites. Data are also presented showing that in vivo expression of the NL1Tc protein conferred viability by complementation to E. coli exonuclease III deletion mutants (BW286 strain). We propose that the biological function of the AP endonuclease activity of the NL1Tc protein may be connected with the introduction into the DNA of free 3' ends that could be used as primers for the integration, along the T. cruzi genome, of the L1Tc element and that the nicking could be a general mechanism for the retrotransposition of non-site-specific non-long terminal repeat retrotransposons.     

The short 3''-end region of complementary DNAs as PCR-based polymorphic markers for an expression map of the mouse genome

All of the protein-encoding exons and the 3' flanking region of the human decorin gene have been cloned and partially sequenced. The locations of the intron-exon junctions within the coding portion of the gene were identical to those found for the homologous human gene, biglycan. The sizes of the introns in the decorin gene, however, were substantially larger than those of the same introns of the biglycan gene. Portions of introns 1, 2, and 3 as well as exon 1 were not found during our extensive screening process. The 5' end of intron 2 was found to have an AG-rich region followed immediately by a CT-rich region. Furthermore, the 5' end of intron 3 was very rich in thymidine, whereas the 3' end of intron 7 was rich in adenosine. Several cDNA clones constructed from cultured human bone cell mRNA were found to contain a different sequence at the 5' end compared to that previously published for mRNA from a human embryonic fibroblast cell line. We were also unable to find the alternate 3' flanking region of the previously published cDNA sequence. We have mapped the human decorin gene by in situ methods to chromosome 12q21.3.     

Sleepiness, alertness and performance during a laboratory simulation of an acute shift of the wake-sleep cycle

Monitoring the presence of sleepiness on the job and its effects on performance is of primary importance for improving schedule systems of shiftworkers. Shiftworkers, often involved in night-time operations and irregular work schedules, frequently complain of nocturnal sleepiness especially in conditions of abrupt shift of the wake-sleep cycle. In this study, the authors evaluated the effects of a laboratory simulation of acute night-shift changes on sleepiness, vigilance and performance, using Maintenance of Wakefulness Test, Multiple Sleep Latency Test and three pencil and paper tests: Digit Symbol Substitution Test, 'Deux Barrages' Test and a 3-Letter Cancellation Task. All of the tests were administered four times at 2-hourly intervals during the night after daytime sleep. Results showed that the ability to maintain wakefulness and to perform simple visuo-attentive tasks is substantially spared during the night. On the other hand, sleep tendency and performance on a more complex and monotonous task (Letter Cancellation Task) reveal, respectively, increasing sleepiness and degrading performance.     

windbeutel, a gene required for dorsoventral patterning in Drosophila, encodes a protein that has homologies to vertebrate proteins of the endoplasmic reticulum

The formation of the dorsoventral axis of the Drosophila embryo depends on cell-cell interactions that take place in the female ovary and involve the activation of transmembrane receptors by secreted ligands. The gene windbeutel functions in the somatic follicle cells of the ovary and is required for the generation of a signal that will determine the ventral side of the embryo. This signal originates in the follicle cells during oogenesis, but its actions are only manifested after fertilization, when the egg has already been laid. We have performed a molecular analysis of windbeutel. We have found that windbeutel encodes a putative resident protein of the endoplasmic reticulum, and has homologs in rats and humans. The gene is expressed for a brief period of time in the follicle cells of the ovary, at around the time when the dorsoventral axis of the egg chamber is first established. We propose that Windbeutel is responsible for the folding and/or modification of a specific factor that is secreted from the follicle cells and participates in the activation of the ventralizing signal.     

Molecular evolution of a duplication: the sex-peptide (Acp70A) gene region of Drosophila subobscura and Drosophila madeirensis

In Drosophila melanogaster, the Acp70A gene, which is involved in the postmating reactions of the female, is a single-copy gene. However, in Drosophila subobscura, the gene is duplicated and both copies are transcribed. To study the molecular evolution of the duplication, a 2.1-kb fragment encompassing both copies of the duplication was sequenced for 10 lines of D. subobscura and one line of Drosophila madeirensis. Estimates of the divergence between the two copies of the duplicated region and between the two species studied, D. subobscura and D. madeirensis, revealed that both copies of the Acp70a gene had evolved independently since their duplication. The ratio of nonsynonymous to silent divergence between copies was generally higher than one. The McDonald and Kreitman test revealed an excess of nonsynonymous changes fixed since the duplication and before the split of the D. subobscura and D. madeirensis lineages. These results point to natural selection driving protein evolution after the duplication. Specifically, adaptive evolution appears to have caused the initial differentiation between copies of the N-terminal parts of the proteins, while purifying selection could be responsible for the high conservation of the C-terminal parts.     

The gene product of human cytomegalovirus open reading frame UL56 binds the pac motif and has specific nuclease activity

Using the cis-acting human cytomegalovirus (HCMV) packaging elements (pac 1 and pac 2) as DNA probes, specific DNA-protein complexes were detected by electrophoretic mobility shift assay (EMSA) in both HCMV-infected cell nuclear extracts and recombinant baculovirus-infected cell extracts containing the HCMV p130 (pUL56) protein. DNA-binding proteins, which were common in uninfected and infected cell extracts, were also detected. Mutational analysis showed that only the AT-rich core sequences in these cis-acting motifs, 5'-TAAAAA-3' (pac 1) and 5'-TTTTAT-3' (pac 2), were required for specific DNA-protein complex formation. The specificity of the DNA-protein complexes was confirmed by EMSA competition. Furthermore, a specific endonuclease activity was found to be associated with lysates of baculovirus-infected cells expressing recombinant p130 (rp130). This nuclease activity was time dependent, related to the amount of rp130 in the assay, and ATP independent. Nuclease activity remained associated with rp130 after partial purification by sucrose gradient centrifugation, suggesting that this activity is a property of HCMV p130. We propose a possible involvement of p130 in HCMV DNA packaging.     

Math, verbal, and general academic self-concept: The internal/external frame of reference model and gender differences in self-concept structure.

Tested predictions from H. W. Marsh's (see record 1987-17104-001) internal/external (I/E) frame of reference model (measuring cognitive dimensions of math and verbal self-concepts [S-Cs]), and gender differences in the structure of academic S-C were examined through path analyses of data from 231 Norwegian 6th-grade students (117 boys and 114 girls). Math and verbal S-Cs on a cognitive level were defined as success expectations on defined tasks. No strong support was found for the I/E model: Math and verbal S-Cs were highly correlated, and no significant negative direct effects were found of verbal achievement on math S-C or of math achievement on verbal S-C for boys, although a negative direct effect of verbal achievement on math S-C was found for girls. The results differed from previous research measuring evaluative dimensions of math and verbal S-Cs, suggesting either remarkable cultural differences or that academic S-Cs are more complex than has been assumed. The structure of S-C differed for boys and girls; math and verbal S-Cs related differently to general academic S-C. The gender differences are discussed in terms of sex stereotypes. This study has implications for research on academic S-C and gender differences. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Drosophila coracle, a member of the protein 4.1 superfamily, has essential structural functions in the septate junctions and developmental functions in embryonic and adult epithelial cells

Although extensively studied biochemically, members of the Protein 4. 1 superfamily have not been as well characterized genetically. Studies of coracle, a Drosophila Protein 4.1 homologue, provide an opportunity to examine the genetic functions of this gene family. coracle was originally identified as a dominant suppressor of EgfrElp, a hypermorphic form of the Drosophila Epidermal growth factor receptor gene. In this article, we present a phenotypic analysis of coracle, one of the first for a member of the Protein 4. 1 superfamily. Screens for new coracle alleles confirm the null coracle phenotype of embryonic lethality and failure in dorsal closure, and they identify additional defects in the embryonic epidermis and salivary glands. Hypomorphic coracle alleles reveal functions in many imaginal tissues. Analysis of coracle mutant cells indicates that Coracle is a necessary structural component of the septate junction required for the maintenance of the transepithelial barrier but is not necessary for apical-basal polarity, epithelial integrity, or cytoskeletal integrity. In addition, coracle phenotypes suggest a specific role in cell signaling events. Finally, complementation analysis provides information regarding the functional organization of Coracle and possibly other Protein 4.1 superfamily members. These studies provide insights into a range of in vivo functions for coracle in developing embryos and adults.     

Determination of arterial diameters, length and mass of the plaque, and theoretical volume in the internal carotid artery by quantitative vascular echography

To study the evolution of atherosclerosis, the consensual changes that occur in the arterial wall, lumen, and atheroma must be evaluated. The authors propose a new, noninvasive method of obtaining arterial diameters, length and mass of plaque, and theoretical volume in the internal carotid artery. The study was performed in 37 patients with different degrees of atherosclerosis (from 20% to 50%). All patients underwent echo examination. Long-axis tomographic planes were recorded with the same angle of incidence by placing a goniometer around the neck. Furthermore, the arterial diameters and the plaque length were measured from photorecordings, and theoretical arterial volume (sum of two bitruncated semiellipsoids), residual volume (Simpson's integral rule), and plaque mass (difference between theoretical vascular volume and residual volume) were calculated. Intraobserver and interobserver variability and reproducibility were tested in all the measurements and calculations. Intraobserver/interobserver variability and reproducibility were found to be less than 8% according to all measurements and calculations. These results indicate that the method is reproducible and allows noninvasive, quantitative assessments of vascular geometry in evolving atherosclerosis.     

The promoter-proximal, unstable IB region of the atp mRNA of Escherichia coli: an independently degraded region that can act as a destabilizing element

Non-invasive methods for routine monitoring of reproductive states and reproduction control in large colonies of captive Callithrix jacchus have been developed. Immunoactive urinary oestrone-3-conjugates (E1C) were measured during non-conception cycles (n = 5) and pregnancy (n = 7). Using plasma progesterone levels to time ovulation, ovulation was quantitatively estimated by a) calculating the first E1C rise and b) by establishing an E1C threshold. Ovulation was thus defined as taking place 4 days preceding a) the first rise of E1C above follicular-phase levels, or b) a concentration > or = 4.5 micrograms E1C/mg creatinine. Early pregnancy could be determined after day 20 by continued luteal-phase levels of E1C. Secondly, the luteolytic effect of cloprostenol, injected over a wide range of doses and between days 1 and 64 after ovulation/conception, was analysed. Luteolysis was achieved when cloprostenol was administered after day 5 post-ovulation; the luteolytic effect was found not to be dose-dependent. The success of cloprostenol treatment was 87% as confirmed by endocrine monitoring. The methods described are effective and minimize intervention, and are therefore suitable for long-term applications, particularly in combination with behavioural studies.