Skewed X-inactivation patterns in ageing healthy and myelodysplastic haematopoiesis determined by a pyrosequencing based transcriptional clonality assay.

BACKGROUND: Investigation of X-chromosome inactivation patterns (XCIP) by determination of differential CpG-methylation has been widely applied for investigation of female cell clonality. Using this approach the clonal origin of various tumours has been corroborated. Controversially, strong age-related increase of peripheral blood (PB) cell clonality in haematologically healthy female subjects was reported. Recently, transcriptional XCIP ratio analysis challenged these results and questioned the suitability of methylation based clonality assays. METHODS: To reinvestigate XCIP-skewing in CD34, low-density mononuclear bone marrow (BM) as well as PB cells from healthy female subjects and patients with myelodysplastic syndromes (MDS), we established a transcriptional assay using pyrosequencing technique for quantification of single nucleotide polymorphism allele frequencies, representative for XCIP ratios. RESULTS: Our assay provides high sensitivity for XCIP ratio assessment as determined by standard curves, reproducibility, inter-marker correlation as well as correlation with the DNA-methylation based human androgen receptor (HUMARA) assay. Notably, in agreement with most studies investigating this issue, significant age-related increase of XCIP skewing in PB cells from healthy elderly female subjects was confirmed. Moreover, XCIP ratio analysis suggests even stronger clonal manifestation in BM and CD34 cells. In MDS, XCIP skewing levels were distinctively elevated as compared with controls of similar age and higher degrees were associated with poor clinical outcome. CONCLUSIONS: Transcriptional clonal profiling via pyrosequencing allows accurate assessment of XCIP ratios, confirms the validity of the DNA-methylation based HUMARA assay and reveals important insights into ageing healthy and myelodysplastic haematopoiesis.

University Students as Change Agents for Health and Sustainability: A Pilot Study on the Effects of a Teaching Kitchen-Based Planetary Health Diet Curriculum.

Global dietary habits are one of the main drivers of climate change. At the same time, they contribute to 11 million premature deaths every year. This raises the question of how the urgently needed transformation of food systems can be realized. Regardless of their degree paths, all university students, in their role as potential future experts and leaders in their fields, can serve as important change agents in society. In this paper, we (a) introduce a university curriculum in a teaching kitchen setting that is based on the planetary health diet (PHD) of the EAT-Lancet Commission, (b) investigate its feasibility, and (c) analyze its effects on the planetary health diet literacy of a pilot cohort of university students enrolled in various degree programs. We developed seven flipped classroom teaching kitchen sessions based on social cognitive theory (SCT), each consisting of a one-hour seminar with student presentations on various nutrition- and sustainability-related key topics, followed by corresponding two-hour hands-on cooking classes. To assess feasibility, specific questions from the official teaching evaluation of the University of Göttingen were analyzed. Changes in self-assessed planetary health diet literacy were measured using a pre- and post-survey. During the pilot phase, 26 students successfully completed the course. A total of 25 participants responded to the teaching evaluation and expressed high satisfaction with the course, the learning outcomes, and the level of demand. A total of 26 participants completed the pre- and post-survey. At the post-intervention, the students rated their planetary health diet literacy as 21 to 98% higher than before their course participation. The findings of this pilot study indicate that the curriculum was well-received and feasible with the target group, and they demonstrate that the course participation increased the university students' self-assessed ability to disseminate strategies for more sustainable and healthy diets. Through replication at other universities worldwide, the teaching kitchen-based planetary health diet curriculum might foster a social shift towards healthier and more climate-friendly food systems.

Comparison of Effectiveness regarding a Culinary Medicine Elective for Medical Students in Germany Delivered Virtually versus In-Person.

(1) Background: The Culinary Medicine elective at the German medical schools of the universities of Göttingen, Giessen, and Brandenburg is a teaching kitchen-based elective aimed at training medical students on how to improve patient counselling on nutrition and lifestyle medicine topics. This curriculum was either delivered virtually (2021) or in-person (2022/2023). Changes in teaching effectiveness were evaluated. (2) Methods: The elective included seven modules in the teaching kitchen for 3 h each. It consisted of a short introduction and a hands-on interactive cooking part illustrating important dietary principles in different disease groups. The elective was conducted virtually in 2021 in a fully interactive setup using videoconference tools. Students in this cohort attended from their private kitchens whereas students in the in-person cohort (2022/2023) attended the same classes in the teaching kitchen. Standardized comparative self-assessment questionnaires on counselling competencies, nutrition knowledge, eating habits, and mental well-being (WHO-5) before and after the elective were used to determine teaching effectiveness. Paired and unpaired t-tests were performed to evaluate results. (3) Results: A total of 70 students (mean semester 6.3) were included in the virtual cohort, and 80 students (mean semester 6.3) were in the in-person cohort. In both, counselling competencies on 25 nutrition and lifestyle medicine topics increased significantly. Significant changes also occurred in most nutrition knowledge categories. Subjective well-being as well as personal attitudes towards nutrition counselling in medical practice improved significantly during the elective. Healthy eating habits improved in both groups as students ate significantly less unfavourable foods. There were no significant differences between the two groups apart from minor differences in nutrition knowledge. (4) Conclusions: The elective in Culinary Medicine improved students counselling competencies, nutrition knowledge, attitudes, well-being, and eating habits with no relevant difference between virtual and in-person teaching.

Detection of differential mitotic cell age in bone marrow CD34(+) cells from patients with myelodysplastic syndrome and acute leukemia by analysis of an epigenetic molecular clock DNA signature.

OBJECTIVE: Recently, the "epigenetic molecular clock hypothesis" linked increasing DNA methylation in a distinct CpG island in the cardiac-specific homeobox gene (CSX) gene to relative mitotic cell age. To determine mitotic cell age in hematopoietic cells of myelodysplastic syndrome (MDS), acute myeloid leukemia (AML) and acute lymphoblastic leukemia (ALL) patients, we assessed differential CSX methylation patterns in these diseases vs age-adjusted healthy controls. MATERIALS AND METHODS: We performed bisulfite pyrosequencing to analyze CSX methylation in CD34(+) and bone marrow (BM) cells from 53 MDS, 62 AML, 77 ALL patients, and 37 controls. RESULTS: Analysis of MDS CD34(+) and BM cells revealed significantly increasing methylation of CSX in controls < MDS low-risk < MDS high-risk < AML. Furthermore, increased differences of CSX methylation between the CD34(+) vs the unselected BM compartment were detected in matched MDS low-risk but not high-risk and AML samples. ALL samples displayed highly elevated CSX methylation levels as compared to controls. CONCLUSIONS: Assessment of mitotic cell age by CSX methylation analysis could reveal novel insights into the distinct progression of hematologic diseases.

Angular tolerance of Shack-Hartmann wavefront sensors with microaxicons.

Wavefront sensing under nonparaxial conditions was studied with Shack-Hartmann setups based on arrays of microaxicons. The robustness of the generated pseudonondiffracting subbeams against tilt and axial displacement was demonstrated for ultraflat Gaussian- and inverse-Gaussian-shaped elements in transmission and reflection. To characterize slight aberrations and to identify optimum parameter fields, spatial moments of intensity profiles were analyzed with high sensitivity. Reflective design enables for wavefront sensing at oblique incidence as necessary for low-feedback detection and phase diagnostics of ultrashort pulses.

Scalable multichannel micromachining with pseudo-nondiffracting vacuum ultraviolet beam arrays generated by thin-film axicons.

Scalable multichannel microstructuring was demonstrated by multiplexing a focused molecular fluorine laser beam with cylindrical nanolayer microaxicons into an array of converging pseudo-nondiffracting subbeams. The axicons were fabricated by shadow-mask vapor deposition of magnesium fluoride onto substrates of identical material. Long-period surface gratings of variable pitch were generated on poly(methyl methacrylate) by varying the target position within the converging periodic focal lines.

Lipopolysaccharide and porin of Roseobacter denitrificans, confirming its phylogenetic relationship to the alpha-3 subgroup of Proteobacteria.

Roseobacter denitrificans has rough (R)-type lipopolysaccharide, containing 2-keto-3-deoxyoctonate but no hepatoses. Its lipid A has a glucosamine-containing, phosphorylated backbone. It contains the rare 3-oxotetradecanoic (3-oxomyristic) acid as the only amide-bound fatty acid and ester-bound 3-hydroxydecanoic acid, this pattern being characteristic for the alpha-3 subgroup of Proteobacteria. Treatment of the major outer-membrane protein (porin, apparent molecular mass 88 kDa) of Roseobacter denitrificans with EDTA (2 mM, 30 degrees C, 20 min) resulted in the dissociation of the oligomers into monomers (apparent molecular mass 35 kDa). EDTA-sensitive dissociation has so far been observed only within the alpha-3 subgroup of Proteobacteria. The 12 N-terminal amino acids of the monomers exhibit sequence homology with the porins of Rhodobacter capsulatus, Rhodobacter sphaeroides and Rhodopseudomonas blastica. Renaming of Roseobacter denitrificans as Rhodobacter denitrificans is suggested.

Biologically active peptides in cyanobacteria

Las cianobacterias se encuentran en el medio natural tanto en aguas dulces como saladas. Ellas pueden desarrollarse en grandes masas formando "blooms" (florecimientos) en aguas dulces y saladas en diferentes partes del mundo, incluyendo América del Sur. Tales florecimientos, así como crecimientos axénicos de cianobacterias, pueden ser una rica fuente de péptidos lineales o cíclicos únicos, muchos de los cuales presentan actividad biológica. En el pasado la mayor atención ha sido puesta en las toxinas microcistina y nodulatoria. Estos péptidos ciclicos son hepatotoxinas que inhíben la proteína fosfatasa 1 y 2A, después de ingresar específicamente al hepatocito mediante la captación de las sales biliares. Sin embargo, en cianobacterias se están encontrando péptidos con otras actividades biológicas. No obstante, auque no se consideren tóxicos, estos péptidos tienen actividades biológicas tales como: una fuerte y específica inhibición de las proteasas (tripsina, quimo-tripsina, elastasa, trombina, plasmina y la enzima procesadora angiotensina), anticianobacterias, antialgas, antihongos, inmunosupresores y promotores de diferenciación celular. Ejemplos de péptidos cianobacteriales inhibidores de proteasas son las cianopeptolina. Las interacciones de microcistina/proteína fosfatasa y de cianopeptolina/proteasa, han sido bien estudiadas por difracción de rayos x en cocristales y la determinación de microcistina y de otros péptidos puede ser realizada por métodos químicos y biológicos. Ambas, microcistina y cianopeptolina han sido recientemente determinadas en blooms producidos en cuerpos de agua en Chile, utilizando cromatografía líquida de alta resolución (HPLC), espectrometría de masas (MALDI-TOF) (PSD), además de bioensayos de inhibición enzimática