Psychological Adjustment in the Context of Perinatal Cancer

Aims: To assess the influence of pregnancy and recent motherhood on the psychological adjustment to cancer in women diagnosed with a perinatal cancer. Procedure: ECHOCALG is an exploratory and comparative study combining quantitative and qualitative methods. Twenty-four women who had received a perinatal cancer diagnosis (75% had breast cancer, 25% had brain or colon cancer, Hodgkin or melanoma) completed the MAC44 scale and responded to a semi-structured clinical interview to identify the psychological adjustment to cancer. Eighteen of them responded to a semi-structured interview to identify the conditions of psychological adaptation to the disease, as well as the defense mechanisms used. The data were compared with that of a control group of nineteen women diagnosed with non-perinatal and non-metastatic breast cancer, aged less than 45.

Results: Women diagnosed with perinatal cancer showed more difficulty adjusting to the disease than control women. Denial and avoidance are strongly correlated with a negative adjustment to cancer. The interviews showed at the start of treatment the presence of defense mechanisms such as denial and trivialization as well as a suspension of the process of psychological adaptation to the disease and the treatments. The distress of a mother is linked to the feeling of being unable to take care of the baby and to cope concomitantly with motherhood and illness, as well as difficulties related to sexuality and emotional and social support.

Conclusion: Pregnancy and recent motherhood have an impact on the adjustment to cancer. Women with perinatal cancer show a negative adjustment and an important psychological distress linked to difficulties of mothering and physical and emotional consequences of treatment.

[Validation of the questionnaire for assessing the childbirth experience (QACE) in a French population]

BACKGROUND

A woman's negative perception of her subjective childbirth experience can have consequences on the mother's psychological state and on early mother-baby relationships. To date, there is no validated tool in France allowing to evaluate childbirth experience in a multidimensional way. The aim of this study is to validate the Questionnaire Assessing the Childbirth Experience (QEVA) in a French sample of mothers. This tool was developed in a previous study where the authors combined 25 items into 6 dimensions: representations and expectations, sensory perceptions, feeling of control, perceived social support (medical staff and partner), emotions (positive and negative) and first moments with the baby.

METHODS

The sample included 256 women recruited in a maternity ward. Sociodemographic and obstetric characteristics of our sample were compared to those of the French national perinatal survey. The structure of the QEVA with 17 items was explored by an exploratory structural equation modeling (ESEM). An analysis of the internal consistency was conducted on the sub-scores of the identified factors, and the concurrent validity was assessed with the Peri-traumatic Distress Inventory (PDI) through a correlation and its associated t-test.

RESULTS

The characteristics of our sample and those of the national perinatal survey do not differ on age, marital status, parity, cannabis use, infertility treatment, epidural and baby weight, in favour of the good representativeness of our sample. The study of the QEVA structure revealed a 4-dimensional structure. Analysis of the psychometric qualities showed a good internal consistency, with an observed alpha value ranging from 0.69 to 0.86. The QEVA also shows a good concurrent validity with the peri-traumatic distress scores (r=0.51).

CONCLUSION

To date, the QEVA is the first standardized tool allowing a multidimensional evaluation of the subjective experience of childbirth. It has been validated on a French population using an exploratory structural equation modeling. This tool, which is simple to use and well accepted by mothers, enables health professionals not only to screen mothers experiencing difficult childbirth and in need of support, but also to adapt health care according to the dimensions of the birth experience and its associated difficulties (emotions during the birth, interactions with health professionals, first moments with the baby, or post-partum emotions).

Independent measurement of the total active 8B solar neutrino flux using an array of 3He proportional counters at the Sudbury Neutrino Observatory

The Sudbury Neutrino Observatory (SNO) used an array of 3He proportional counters to measure the rate of neutral-current interactions in heavy water and precisely determined the total active (nu_x) 8B solar neutrino flux. This technique is independent of previous methods employed by SNO. The total flux is found to be 5.54_-0.31;+0.33(stat)-0.34+0.36(syst)x10(6) cm(-2) s(-1), in agreement with previous measurements and standard solar models. A global analysis of solar and reactor neutrino results yields Deltam2=7.59_-0.21;+0.19x10(-5) eV2 and theta=34.4_-1.2;+1.3 degrees. The uncertainty on the mixing angle has been reduced from SNO's previous results.

Measurement of the tensor structure function b1 of the deuteron

The Hermes experiment has investigated the tensor spin structure of the deuteron using the 27.6 GeV/c positron beam of DESY HERA. The use of a tensor-polarized deuteron gas target with only a negligible residual vector polarization enabled the first measurement of the tensor asymmetry A(d)zz and the tensor structure function b(d)1 for average values of the Bjorken variable 0.01< <x> <0.45 and of the negative of the squared four-momentum transfer 0.5 GeV2 < <Q2> <5 GeV2. The quantities A(d)zz and b(d)1 are found to be nonzero. The rise of b(d)1 for decreasing values of x can be interpreted to originate from the same mechanism that leads to nuclear shadowing in unpolarized scattering.

Deletion of the dynein heavy-chain gene DYN1 leads to aberrant nuclear positioning and defective hyphal development in Candida albicans

Cytoplasmic dynein is a microtubule-associated minus-end-directed motor protein. CaDYN1 encodes the single dynein heavy-chain gene of Candida albicans. The open reading frames of both alleles of CaDYN1 were completely deleted via a PCR-based approach. Cadyn1 mutants are viable but grow more slowly than the wild type. In vivo time-lapse microscopy was used to compare growth of wild-type (SC5314) and dyn1 mutant strains during yeast growth and after hyphal induction. During yeast-like growth, Cadyn1 strains formed chains of cells. Chromosomal TUB1-GFP and HHF1-GFP alleles were used both in wild-type and mutant strains to monitor the orientation of mitotic spindles and nuclear positioning in C. albicans. In vivo fluorescence time-lapse analyses with HHF1-GFP over several generations indicated defects in dyn1 cells in the realignment of spindles with the mother-daughter axis of yeast cells compared to that of the wild type. Mitosis in the dyn1 mutant, in contrast to that of wild-type yeast cells, was very frequently completed in the mother cells. Nevertheless, daughter nuclei were faithfully transported into the daughter cells, resulting in only a small number of multinucleate cells. Cadyn1 mutant strains responded to hypha-inducing media containing l-proline or serum with initial germ tube formation. Elongation of the hyphal tubes eventually came to a halt, and these tubes showed a defect in the tipward localization of nuclei. Using a heterozygous DYN1/dyn1 strain in which the remaining copy was controlled by the regulatable MAL2 promoter, we could switch between wild-type and mutant phenotypes depending on the carbon source, indicating that the observed mutant phenotypes were solely due to deletion of DYN1.

Single-spin asymmetries in semi-inclusive deep-inelastic scattering on a transversely polarized hydrogen target

Single-spin asymmetries for semi-inclusive electroproduction of charged pions in deep-inelastic scattering of positrons are measured for the first time with transverse target polarization. The asymmetry depends on the azimuthal angles of both the pion (phi) and the target spin axis (phi(S)) about the virtual-photon direction and relative to the lepton scattering plane. The extracted Fourier component sin((phi+phi(S))(pi)(UT) is a signal of the previously unmeasured quark transversity distribution, in conjunction with the Collins fragmentation function, also unknown. The component sin((phi-phi(S)(pi)(UT) arises from a correlation between the transverse polarization of the target nucleon and the intrinsic transverse momentum of quarks, as represented by the previously unmeasured Sivers distribution function. Evidence for both signals is observed, but the Sivers asymmetry may be affected by exclusive vector meson production.

Polarized hyphal growth in Candida albicans requires the Wiskott-Aldrich Syndrome protein homolog Wal1p

The yeast-to-hypha transition is a key feature in the cell biology of the dimorphic human fungal pathogen Candida albicans. Reorganization of the actin cytoskeleton is required for this dimorphic switch in Candida. We show that C. albicans WAL1 mutants with both copies of the Wiskott-Aldrich syndrome protein (WASP) homolog deleted do not form hyphae under all inducing conditions tested. Growth of the wild-type and wal1 mutant strains was monitored by in vivo time-lapse microscopy both during yeast-like growth and under hypha-inducing conditions. Isotropic bud growth produced round wal1 cells and unusual mother cell growth. Defects in the organization of the actin cytoskeleton resulted in the random localization of actin patches. Furthermore, wal1 cells exhibited defects in the endocytosis of the lipophilic dye FM4-64, contained increased numbers of vacuoles compared to the wild type, and showed defects in bud site selection. Under hypha-inducing conditions wal1 cells were able to initiate polarized morphogenesis, which, however, resulted in the formation of pseudohyphal cells. Green fluorescent protein (GFP)-tagged Wal1p showed patch-like localization in emerging daughter cells during the yeast growth phase and at the hyphal tips under hypha-inducing conditions. Wal1p-GFP localization largely overlapped with that of actin. Our results demonstrate that Wal1p is required for the organization of the actin cytoskeleton and hyphal morphogenesis in C. albicans as well as for endocytosis and vacuole morphology.

Flavor decomposition of the sea-quark helicity distributions in the nucleon from semiinclusive deep inelastic scattering

Double-spin asymmetries of semiinclusive cross sections for the production of identified pions and kaons have been measured in deep inelastic scattering of polarized positrons on a polarized deuterium target. Five helicity distributions including those for three sea quark flavors were extracted from these data together with reanalyzed previous data for identified pions from a hydrogen target. These distributions are consistent with zero for all three sea flavors. A recently predicted flavor asymmetry in the polarization of the light quark sea appears to be disfavored by the data.

The development of a transformation system for the dimorphic plant pathogen Holleya sinecauda based on Ashbya gossypii DNA elements

We have developed a transformation system for the dimorphic plant pathogenic fungus Holleya sinecauda based on an electroporation protocol used for the closely related filamentous fungus Ashbya gossypii. DNA-mediated transformation of the dominant selection marker kanMX generated H. sinecauda transformants that were resistant to the antibiotic drug G418/geneticin. Freely replicating plasmids could be established in H. sinecauda using an A. gossypii autonomously replicating sequence (ARS) element, whereas Saccharomyces cerevisiae ARS elements, which are functional in A. gossypii, were not functional in H. sinecauda. In addition, centromeric DNA of A. gossypii stabilized the maintenance of plasmids in H. sinecauda under non-selective conditions. We isolated a fragment of the HsLEU2 gene and used this locus for targeted integration of kanMX3, consisting of the kanMX gene flanked by direct repeats. This allowed the construction of a Hsleu2 strain which became G418 sensitive after direct repeat-induced marker excision. The Hsleu2 strain can be complemented by the ScLEU2 gene. Finally, we constructed high- and low-copy shuttle vectors for H. sinecauda.

Evidence for quark-hadron duality in the proton spin asymmetry A1

Spin-dependent lepton-nucleon scattering data have been used to investigate the validity of the concept of quark-hadron duality for the spin asymmetry A1. Longitudinally polarized positrons were scattered off a longitudinally polarized hydrogen target for values of Q2 between 1.2 and 12 GeV2 and values of W2 between 1 and 4 GeV2. The average double-spin asymmetry in the nucleon resonance region is found to agree with that measured in deep-inelastic scattering at the same values of the Bjorken scaling variable x. This finding implies that the description of A1 in terms of quark degrees of freedom is valid also in the nucleon resonance region for values of Q2 above 1.6 GeV2.

Q2 dependence of nuclear transparency for exclusive rho0 production

Exclusive coherent and incoherent electroproduction of the rho(0) meson from 1H and 14N targets has been studied at the HERMES experiment as a function of coherence length (l(c)), corresponding to the lifetime of hadronic fluctuations of the virtual photon, and squared four-momentum of the virtual photon (-Q2). The ratio of 14N to 1H cross sections per nucleon, called nuclear transparency, was found to increase (decrease) with increasing l(c) for coherent (incoherent) rho(0) electroproduction. For fixed l(c), a rise of nuclear transparency with Q2 is observed for both coherent and incoherent rho(0) production, which is in agreement with theoretical calculations of color transparency.

Comparison of morphogenetic networks of filamentous fungi and yeast

Fungi generally display either of two growth modes, yeast-like or filamentous, whereas dimorphic fungi, upon environmental stimuli, are able to switch between the yeast-like and the filamentous growth mode. Signal transduction pathways have been elucidated in the budding yeast Saccharomyces cerevisiae, establishing a morphogenetic network that links cell-cycle events with cellular morphogenesis. Recent molecular genetic studies in several filamentous fungal model systems revealed key components required for distinct steps from fungal spore germination to the maintenance of polar hyphal growth, mycelium formation, and nuclear division. This allows a mechanistic comparison of yeast-like and hyphal growth and the establishment of a core model morphogenetic network for filamentous growth including signaling via the cAMP pathway, Rho modules, and cell cycle kinases. Appreciating similarities between morphogenetic networks of the unicellular yeasts and the multicellular filamentous fungi will open new research directions, help in isolating the central network components, and ultimately pave the way to elucidate the central differences (of many) that distinguish, e.g., the growth mode of filamentous fungi from that of their yeast-like relatives, the role of cAMP signaling, and nuclear division.

Cell polarity and hyphal morphogenesis are controlled by multiple rho-protein modules in the filamentous ascomycete Ashbya gossypii

Polarized cell growth requires a polarized organization of the actin cytoskeleton. Small GTP-binding proteins of the Rho-family have been shown to be involved in the regulation of actin polarization as well as other processes. Hyphal growth in filamentous fungi represents an ideal model to investigate mechanisms involved in generating cell polarity and establishing polarized cell growth. Since a potential role of Rho-proteins has not been studied so far in filamentous fungi we isolated and characterized the Ashbya gossypii homologs of the Saccharomyces cerevisiae CDC42, CDC24, RHO1, and RHO3 genes. The AgCDC42 and AgCDC24 genes can both complement conditional mutations in the S. cerevisiae CDC42 and CDC24 genes and both proteins are required for the establishment of actin polarization in A. gossypii germ cells. Agrho1 mutants show a cell lysis phenotype. Null mutant strains of Agrho3 show periodic swelling of hyphal tips that is overcome by repolarization and polar hyphal growth in a manner resembling the germination pattern of spores. Thus different Rho-protein modules are required for distinct steps during polarized hyphal growth of A. gossypii.

Evidence for a single-spin azimuthal asymmetry in semi-inclusive pion electroproduction

Single-spin asymmetries for semi-inclusive pion production in deep-inelastic scattering have been measured for the first time. A significant target-spin asymmetry of the distribution in the azimuthal angle straight phi of the pion relative to the lepton scattering plane was formed for pi(+) electroproduction on a longitudinally polarized hydrogen target. The corresponding analyzing power in the sinstraight phi moment of the cross section is 0.022+/-0.005+/-0.003. This result can be interpreted as the effect of terms in the cross section involving chiral-odd spin distribution functions in combination with a chiral-odd fragmentation function that is sensitive to the transverse polarization of the fragmenting quark.

Determination of cell polarity in germinated spores and hyphal tips of the filamentous ascomycete Ashbya gossypii requires a rhoGAP homolog

In the filamentous ascomycete Ashbya gossypii, like in other filamentous fungi onset of growth in dormant spores occurs as an isotropic growth phase generating spherical germ cells. Thereafter, a switch to polarized growth results in the formation of the first hyphal tip. The initial steps of hyphal tip formation in filamentous fungi, therefore, resemble processes taking place prior to and during bud emergence of unicellular yeast-like fungi. We investigated whether phenotypic similarities between these distinct events extended to the molecular level. To this end we isolated and characterized the A. gossypii homolog of the Saccharomyces cerevisiae BEM2 gene which is part of a network of rho-GTPases and their regulators required for bud emergence and bud growth in yeast. Here we show that the AgBem2 protein contains a GAP- (GTPase activating protein) domain for rho-like GTPases at its carboxy terminus, and that this part of AgBem2p is required for complementation of an Agbem2 null strain. Germination of spores resulted in enlarged Agbem2 germ cells that were unable to generate the bipolar branching pattern found in wild-type germ cells. In addition, mutant hyphae were swollen due to defects in polarized cell growth indicated by the delocalized distribution of chitin and cortical actin patches. Surprisingly, the complete loss of cell polarity which lead to spherical hyphal tips was overcome by the establishment of new cell polarities and the formation of multiple new hyphal tips. In conclusion these results and other findings demonstrate that establishment of cell polarity, maintenance of cell polarity, and polarized hyphal growth in filamentous fungi require members of Ρ-GTPase modules.

PCR-based gene targeting in the filamentous fungus Ashbya gossypii

We have investigated a PCR-based approach for one-step gene targeting in the filamentous fungus Ashbya gossypii. Short guide sequences with 40-46 bp of homology to two sequences of a targeted gene, provided by PCR, were sufficient to mediate homologous recombination. The PCR products used for transformation were generated from the newly constructed chimeric selection marker GEN3. This consists of the open reading frame of the Escherichia coli kanR gene under the control of promoter and terminator sequences of the Saccharomyces cerevisiae TEF2 gene and allows selection of G418/geneticin-resistant transformants. Verification of gene targeting was performed either by PCR or by DNA hybridization analyses, and in all 18 cases tested, correct targeting was confirmed. This approach was used for the complete deletion of the open reading frame of the A. gossypii RHO4 gene for which a double-strand sequence was available as information source for the design of PCR primers. We also demonstrated successful partial deletion of four other ORFs using single-read sequences (SRS) as sole information for the design of targeting primers. A gossypii is the first filamentous fungus in which a PCR-based gene disruption technique has been established. Since short target guide sequences are sufficient to direct homologous integration into the A. gossypii genome it is not necessary to obtain and sequence large DNA fragments from a target locus to provide the long flanking homology regions usually required for efficient targeting of cloned disruption cassettes in filamentous fungi. Thus functional analysis of A. gossypii genes is already possible, based on single-pass sequence information.

Compact organization of rRNA genes in the filamentous fungus Ashbya gossypii

The rDNA cluster in the phytopathogenic fungus Ashbya gossypii consists of approximately 50 tandem repeat units of 8197 bp. Each unit carries a gene for the 35S pre-rRNA, processed into 18S, 5.8S and 25S rRNA, and a divergently transcribed gene for 5S rRNA. The well-characterized rDNA of the yeast Saccharomyces cerevisiae is the only other example of a completely sequenced rDNA unit (9137 bp) carrying both a 35S pre-rRNA and a 5S rRNA gene. The coding regions for the 5S, 5.8S, 18S and 25S rRNAs are 95-100% identical whereas transcribed and non-transcribed spacers show 43-66% sequence identity. Functionally characterized rDNA and rRNA elements of S. cerevisiae can be unambiguously recognized in the A. gossypii sequence, including the RNA polymerase-I transcription start site, two Reb1p enhancer binding sites and numerous recognition sequences for rRNA modification and processing. In addition to these functionally characterized sequences eight highly conserved elements from 10 to 71 bp were detected in the over 600-bp transcribed region upstream of the 18S rRNA gene which most likely play as yet uncharacterized functions at the DNA or RNA level. In addition to this work we started to identify A. gossypii homologs of S. cerevisiae nucleolar proteins involved in rDNA maturation.

Allelic divergence at B alpha 1 pheromone receptor genes of Schizophyllum commune

The multiallelic mating type locus B alpha 1 of Schizophyllum commune encodes a pheromone receptor and putative pheromone genes. A comparison of two alleles encoding receptors that share the same specificity B alpha 1 was performed using strains of different geographic origin. The amino acid sequence alignment revealed strong conservation of the largest part of the receptor. Only in the distal C-terminus major amino acid was divergence encountered. This C-terminal region of 117 of the total of 639 amino acids was shown to be unnecessary for function in vivo by transformation experiments.

The mating-type locus B alpha 1 of Schizophyllum commune contains a pheromone receptor gene and putative pheromone genes

Analysis of the multispecific B alpha mating-type locus of Schizophyllum commune provided evidence that pheromones and pheromone receptors govern recognition of self versus non-self and sexual development in this homobasidiomycetous fungus. Four subclones of an 8.2 kb genomic fragment carrying B alpha 1 specificity induced B-regulated sexual morphogenesis when introduced into a strain with one of the eight compatible B alpha specificities that are known to exist in nature. One of these clones, which activated all other B alpha specificities, contains a gene termed bar1. The predicted protein product of bar1, as well as that of bar2, a homologous gene isolated from a B alpha 2 strain, has significant homology to known fungal pheromone receptor proteins in the rhodopsin-like superfamily of G protein-linked receptors. The other three active B alpha 1 clones were subcloned further to identify the minimal active element in each clone. Every active subclone contains a putative pheromone gene ending in a signal for possible isoprenylation. A message of approximately 600 bp was observed for one of these genes, bap1(1). This paper presents the first evidence for a system of multiple pheromones and pheromone receptors as a basis for multispecific mating types in a fungus.

Homologous recombination as the main mechanism for DNA integration and cause of rearrangements in the filamentous ascomycete Ashbya gossypii

A slow and a fast growth phenotype were observed after transformation of the phytopathogenic fungus Ashbya gossypii using a plasmid carrying homologous DNA and as selectable marker the Tn903 aminoglycoside resistance gene expressed from a strong A. gossypii promoter. Transformations with circular plasmids yielded slowly and irregularly growing geneticin-resistant mycelia in which 1% of nuclei contained plasmid sequences. Occasionally, fast growing sectors appeared which were shown to be initiated by homologous integration of the transforming DNA. Transformants obtained with plasmids linearized within the homology region immediately exhibited fast radial growth. In all 28 transformants analyzed plasmid DNA was integrated homologously. Such apparent lack of nonhomologous recombination has so far not been observed in filamentous ascomycetes. In 14 transformants two to four tandemly integrated plasmid copies were found. They underwent several types of genetic changes, mainly in the older mycelium: excision of whole plasmid copies and rearrangements within the integrated DNA (inversions and deletions). These internal rearrangements involved 360-bp inverted repeats, remnants of IS-elements flanking the resistance gene, and 156-bp direct repeats, originating from the strong A. gossypii promoter. Improved vectors lacking sequence repetitions were constructed and used for stable one-step gene replacement in A. gossypii.