Role of biotin-containing membranes and nuclear distribution in differentiating human endometrial cells

Human Ishikawa endometrial cells form domes when confluent monolayers are stimulated with fresh fetal bovine serum. Extensive structural and biochemical changes have been detected during the approximately 30 h differentiation period. The earliest detectable change involves the formation of multinucleated structures and the appearance of “granules” that stain for biotin within those structures. Nuclei become associated with each other and are ultimately enclosed within a biotin-containing membrane. Aggregated membrane-sheathed nuclei and the cells containing them begin to elevate from the dish as biotin staining becomes apparent in apical membranes. The elevated structures are called predomes and consist of one or more very large cells containing the sheathed nuclei. Apical membranes of these unusual cells extend far out into the medium in structures that resemble endometrial pinopods. A lumen under the elevated cells fills with transcytosed fluid. As differentiation proceeds, highly concentrated chromatin material that was flattened against apical and lateral membranes of the predome cells begins to disperse. Small mononuclear cells evolve from larger predome cells. Apical membranes of predome and dome cells continue to stain for biotin. Gel electrophoresis of SDS-solubilized biotin-containing membranes, followed by Western blot analysis using avidin-linked peroxidase, resulted in three stained bands with molecular weights similar to those of the mitochondrial carboxylases: propionyl carboxylase, methylmalonyl carboxylase, and pyruvate carboxylase. J. Cell. Biochem. 71:400–415, 1998. © 1998 Wiley-Liss, Inc.     

High-resolution palynology reveals the land use history of a Sami <Emphasis Type="Italic">renvall</Emphasis> in northern Sweden

The limited availability of historical and archaeological evidence means that much is still unknown about the development of Sami reindeer herding in Fennoscandia in both the recent and more distant past. To address this problem, high-resolution palynological analyses, ¹⁴C and ²¹⁰Pb dating were undertaken on two adjacent (<25 m apart) peat profiles collected at a recently abandoned reindeer gathering pen (renvall) near Jokkmokk (~66.6°N, 19.8°E) in the boreal forest of northern Sweden. The aim was to assess the impact of Sami reindeer herding on the local environment through a study of pollen, coprophilous fungal spores, microscopic charcoal and sedimentology. The samples collected from within an annex to the renvall indicate cycles of use and abandonment of the pen on a multi-decadal timescale between ~ad 1800–2008, most obviously in the coprophilous fungal spore archive. The pattern and timing of these cycles confirm events previously known only from oral histories. Although the local pollen assemblage zones associated with the phasing of activity were reproducible in a second peat core beyond the boundary of the renvall, the coprophilous fungal spore signal in this paired profile was much less distinctive, possibly due to the typically shorter dispersal distances for these microfossils in comparison to pollen grains.     

Association genetics of phenolic needle compounds in Norway spruce with variable susceptibility to needle bladder rust

Key message

Accumulation of phenolic needle metabolites in Norway spruce is regulated by many genes with small and additive effects and is correlated with the susceptibility against fungal attack.

Abstract

Norway spruce accumulates high foliar concentrations of secondary phenolic metabolites, with important functions for pathogen defence responses. However, the molecular genetic basis underlying the quantitative variation of phenolic compounds and their role in enhanced resistance of spruce to infection by needle bladder rust are unknown. To address these questions, a set of 1035 genome-wide single nucleotide polymorphisms (SNPs) was associated to the quantitative variation of four simple phenylpropanoids, eight stilbenes, nine flavonoids, six related arithmetic parameters and the susceptibility to infection by Chrysomyxa rhododendri in an unstructured natural population of Norway spruce. Thirty-one significant genetic associations for the flavonoids gallocatechin, kaempferol 3-glucoside and quercetin 3-glucoside and the stilbenes resveratrol, piceatannol, astringin and isorhapontin were discovered, explaining 22–59% of phenotypic variation, and indicating a regulation of phenolic accumulation by many genes with small and additive effects. The phenolics profile differed between trees with high and low susceptibility to the fungus, underlining the importance of phenolic compounds in the defence mechanisms of Norway spruce to C. rhododendri. Results highlight the utility of association studies in non-model tree species and may enable marker-assisted selection of Norway spruce adapted to severe pathogen attack.

     

Sperm-derived histones contribute to zygotic chromatin in humans

Background

about 15% to 30% of the DNA in human sperm is packed in nucleosomes and transmission of this fraction to the embryo potentially serves as a mechanism to facilitate paternal epigenetic programs during embryonic development. However, hitherto it has not been established whether these nucleosomes are removed like the protamines or indeed contribute to paternal zygotic chromatin, thereby potentially contributing to the epigenome of the embryo.

Results

to clarify the fate of sperm-derived nucleosomes we have used the deposition characteristics of histone H3 variants from which follows that H3 replication variants present in zygotic paternal chromatin prior to S-phase originate from sperm. We have performed heterologous ICSI by injecting human sperm into mouse oocytes. Probing these zygotes with an antibody highly specific for the H3.1/H3.2 replication variants showed a clear signal in the decondensed human sperm chromatin prior to S-phase. In addition, staining of human multipronuclear zygotes also showed the H3.1/H3.2 replication variants in paternal chromatin prior to DNA replication.

Conclusion

these findings reveal that sperm-derived nucleosomal chromatin contributes to paternal zygotic chromatin, potentially serving as a template for replication, when epigenetic information can be copied. Hence, the execution of epigenetic programs originating from transmitted paternal chromatin during subsequent embryonic development is a logical consequence of this observation.     

Long-term effects of STN DBS on mood: psychosocial profiles remain stable in a 3-year follow-up

Background

Deep brain stimulation of the subthalamic nucleus significantly improves motor function in patients with severe Parkinson's disease. However, the effects on nonmotor aspects remain uncertain. The present study investigated the effects of subthalamic nucleus deep brain stimulation on mood and psychosocial functions in 33 patients with advanced Parkinson's disease in a three year follow-up.

Methods

Self-rating questionnaires were administered to 33 patients prior to surgery as well as three, six, twelve and 36 months after surgery.

Results

In the long run, motor function significantly improved after surgery. Mood and psychosocial functions transiently improved at one year but returned to baseline at 36 months after surgery. In addition, we performed cluster and discriminant function analyses and revealed four distinct psychosocial profiles, which remained relatively stable in the course of time. Two profiles featured impaired psychosocial functioning while the other two of them were characterized by greater psychosocial stability.

Conclusion

Compared to baseline no worsening in mood and psychosocial functions was found three years after electrode implantation. Moreover, patients can be assigned to four distinct psychosocial profiles that are relatively stable in the time course. Since these subtypes already exist preoperatively the extent of psychosocial support can be anticipatory adjusted to the patients' needs in order to enhance coping strategies and compliance. This would allow early detection and even prevention of potential psychiatric adverse events after surgery. Given adequate psychosocial support, these findings imply that patients with mild psychiatric disturbances should not be excluded from surgery.

     

Diversity of Vibrios associated with reared clams in Galicia (NW Spain)

The aim of the present study was to characterize and identify vibrios isolated from cultured clams in Galicia (NW Spain). A total of 759 isolates were obtained, phenotypically characterized, grouped and assigned to the genus Vibrio. Subsequently, the genomic diversity of 145 representative strains was analyzed by means of amplified fragment length polymorphism (AFLP), which revealed a high genetic diversity amongst these isolates. Only 57 out of 145 strains could be identified to the species level, and they were distributed in 13 AFLP clusters. V. cyclitrophicus, V. splendidus and V. alginolyticus were the most abundantly represented species. Eighty-eight isolates remained unidentified, 59 were distributed over 16 clusters, while 29 were unclustered. Sequencing of the 16S rRNA and two house-keeping genes (rpoA and recA) from representative strains belonging to eight unidentified clusters with the highest number of isolates confirmed their assignation to the Vibrionaceae family, and some of these probably represent new species within the genus. The present study confirmed that the phenotypic characterization of vibrios is not sufficient to identify them at the species level. A wide diversity of vibrios was found in cultured clams from all four geographic locations analyzed. In total, more than 12 Vibrio species and at least three potential new species in this genus were identified.     

Vaginal oestrus during the reproductive and non-reproductive period in European ground squirrels

Most hibernating animals are thought to be monoestrous because reproductive activity is subject to strong time constraints. In previous studies, female European ground squirrels (Spermophilus citellus) turned out to have elevated oestradiol levels during late lactation and after weaning, indicating ovarian activity during summer. Therefore, we monitored vaginal cytology, endocrine changes, and vulval development in semi-free-living female European ground squirrels throughout one active season. Vaginal oestrus, defined by the predominance of cornified cells in smear samples, was found during the mating period shortly after vernal emergence. This phase was followed by metoestrus, characterised by the appearance of leukocytes, and a subsequent anoestrous phase. During weaning or postlactation, a second vaginal oestrus was documented in all experimental females, again followed by a metoestrous and an anoestrous phase lasting until hibernation. In line with the second vaginal oestrus, plasma oestradiol concentrations peaked during postlactation. Progesterone levels were elevated from gestation to postlactation, and titres were marginally higher during vaginal oestrus in summer than in spring. Vulval swelling was more pronounced during the first than the second vaginal oestrus. The second oestrous cycle was non-reproductive, as males were sexually inactive with regressed testes during summer. We assume that the second oestrous cycle and the accompanying endocrine changes have beneficial effects on prehibernatory fattening and reproductive performance in the subsequent season. This might allow females to become oestrous immediately after emergence from hibernation in spring.