Prenatal Screening and Genetics

Although the term 'genetic screening' has been used for decades, this paper discusses how, in its most precise meaning, genetic screening has not yet been widely introduced. 'Prenatal screening' is often confused with 'genetic screening'. As we show, these terms have different meanings, and we examine definitions of the relevant concepts in order to illustrate this point. The concepts are i) prenatal, ii) genetic screening, iii) screening, scanning and testing, iv) maternal and foetal tests, v) test techniques and vi) genetic conditions. So far, prenatal screening has little connection with precisely defined genetics. There are benefits but also disadvantages in overstating current links between them in the term genetic screening. Policy making and professional and public understandings about screening could be clarified if the distinct meanings of prenatal screening and genetic screening were more precisely observed

Comparison of relaxation properties of collagen gel MRI phantoms at multiple magnetic fields

Abstract. Osteoarthritis (OA) is the most common joint disorder in the world. OA affects the articular cartilage of synovial joints, causing disabilities and pain to those affected by the disease. The early stages of OA mainly affect the collagen and proteoglycan content of articular cartilage, causing it to lose its mechanical strength and start degrading. Magnetic resonance imaging (MRI) is a popular, non-invasive tool in OA diagnostics as it has the capability to detect morphological lesions and changes in the chemical composition of articular cartilage. In this thesis, an MRI phantom study was designed and performed with the aim to investigate the effect of collagen and chondroitin sulfate (CS) concentration on the relaxation properties of gel-based phantoms at different magnetic field strengths. Three series of MRI phantoms as gels containing collagen and CS were made and dried to obtain final concentrations of collagen between 20–60 mg/g and CS between 0–40 mg/g. Three different relaxation properties were measured of the phantoms; R1 and R2 relaxation rates of the phantoms were measured at three different MRI field strengths (1.5, 3.0, and 9.4 T). Measurements at 1.5 and 3.0 T measurements were performed at Oulu University Hospital, while 9.4 T measurements were performed in Kuopio at the University of Eastern Finland. Additionally, R1rho relaxation rates were measured at 9.4 T with multiple spin-lock frequencies. From the measurements, it was determined that R1 rates of the gels increased with the collagen concentration, while R2 values were similar between the different series at lower magnetic fields but were noticeably higher and increased with increasing CS concentration at 9.4 T. R1rho values increased with both collagen and CS content but the amplitude of the spin-lock pulse had next to no effect on the relaxation rates.Tiivistelmä. Nivelrikko on maailman yleisin nivelsairaus, joka vaikuttaa kantavien nivelten nivelrustoon, aiheuttaen kipua ja liikuntakyvyn sekä elämänlaadun heikkenemistä. Nivelrikon varhainen vaihe vaikuttaa pääasiassa nivelruston kollageeni- ja kondroitiinisulfaattipitoisuuteen, johtaen ruston mekaanisen vahvuuden ja kantokyvyn heikentymiseen ja lopulta ruston rappeutumiseen. Magneettikuvaus eli MRI on yksi suosituimmista nivelrikon diagnosointitavoista, sillä se kykenee havaitsemaan muutoksia ruston kemiallisessa rakenteessa ilman niveleen kajoamista esim. tähystysleikkauksen kautta. Tässä opinnäytteessä kuvaillaan MRI-kuvantamisfantomitutkimusta, jonka päämääränä oli tutkia nivelruston olennaisimpien rakenneosien eli kollageenin ja kondroitiinisulfaatin konsentraatioiden vaikutusta relaksaationopeuteen erivahvuisissa magneettikentissä. Tutkimuksessa tehtiin kolme geelipohjaista MRI-fantomisarjaa, joissa kollageenin lopullinen konsentraatio vaihteli sarjan mukaan 20–60 mg/g välillä, kun taas kondroitiinisulfaatin konsentraatio oli 0–40 mg/g. Erilaisia magneettikuvauslaitteita käytettiin ulkoisen magneettikentän vahvuuden ja relaksaationopeuksien yhteyden selvittämiseksi; mittaukset 1.5 ja 3.0 Teslassa tehtiin Oulun yliopistollisessa sairaalassa, kun taas mittaukset 9.4 Teslassa suoritettiin Kuopiossa, Itä-Suomen yliopistossa. Kolme relaksaationopeutta mitattiin geeleistä; R1- ja R2-nopeudet mitattiin kolmessa erivahvuisessa magneettikentässä (1.5, 3.0 ja 9.4 T). Lisäksi R1rho-arvot mitattiin 9.4 Teslassa usealla "spin-lock" -taajuudella, jotta taajuuden amplitudin vaikutus relaksaationopeuteen saataisiin selville. Tutkimuksen lopputuloksena saatiin, että geelien R1-nopeudet kasvoivat lisääntyneen kollageenikonsentraation myötä. Toisaalta R2-arvot olivat samankaltaisia keskenään heikommissa magneettikentissä konsentraatioista riippumatta, mutta olivat selvästi suurempia ja kasvoivat suurentuneen kondroitiinisulfaattikonsentraation myötä 9.4 Teslassa. R1ρ-nopeudet kasvoivat sekä suurentuneen kollageeni- että kondroitiinisulfaattipitoisuuden myötä, mutta "spin-lock" -taajuudella ei ollut juurikaan vaikutusta nopeuksiin

Comparison of alternative integration sites in the chromosome and the native plasmids of the cyanobacterium Synechocystis sp. PCC 6803 in respect to expression efficiency and copy number

Background: Synechocystis sp. PCC 6803 provides a well-established reference point to cyanobacterial metabolic engineering as part of basic photosynthesis research, as well as in the development of next-generation biotechnological production systems. This study focused on expanding the current knowledge on genomic integration of expression constructs in Synechocystis, targeting a range of novel sites in the chromosome and in the native plasmids, together with established loci used in literature. The key objective was to obtain quantitative information on site-specific expression in reference to replicon copy numbers, which has been speculated but never compared side by side in this host. Results: An optimized sYFP2 expression cassette was successfully integrated in two novel sites in Synechocystis chromosome (slr0944; sll0058) and in all four endogenous megaplasmids (pSYSM/slr5037-slr5038; pSYSX/slr6037; pSYSA/slr7023; pSYSG/slr8030) that have not been previously evaluated for the purpose. Fluorescent analysis of the segregated strains revealed that the expression levels between the megaplasmids and chromosomal constructs were very similar, and reinforced the view that highest expression in Synechocystis can be obtained using RSF1010-derived replicative vectors or the native small plasmid pCA2.4 evaluated in comparison. Parallel replicon copy number analysis by RT-qPCR showed that the expression from the alternative loci is largely determined by the gene dosage in Synechocystis, thereby confirming the dependence formerly proposed based on literature. Conclusions: This study brings together nine different integrative loci in the genome of Synechocystis to demonstrate quantitative differences between target sites in the chromosome, the native plasmids, and a RSF1010-based replicative expression vector. To date, this is the most comprehensive comparison of alternative integrative sites in Synechocystis, and provides the first direct reference between expression efficiency and replicon gene dosage in the context. In the light of existing literature, the findings support the view that the small native plasmids can be notably more difficult to target than the chromosome or the megaplasmids, and that the RSF1010-derived vectors may be surprisingly well maintained under non-selective culture conditions in this cyanobacterial host. Altogether, the work broadens our views on genomic integration and the rational use of different integrative loci versus replicative plasmids, when aiming at expressing heterologous genes in Synechocystis.The research was financially supported by the Academy of Finland Centre of Excellence (#307335), NordForsk Nordic Centre of Excellence (#82845) and Jane and Aatos Erkko Foundation (#4605–26422). The work also received funding from the European Union’s Horizon 2020 research and innovation programme under the Marie Skłodowska-Curie Action—Innovative Training Network 2017 (#764920), and Fundação para a Ciência e a Tecnologia (CEECIND/00259/2017 to CCP)

Vuosikatsaus viestialaan

Johdannossa todetaan, että katsauksen painopiste on vuoden 1995 kehityksessä, "mutta samalla esitetään joitakin edellisen selostuksen jälkeen todettuja vanhempiakin asioita". Edellinen katsaus oli tehty 1953. Toisessa luvussa tarkastellaan viestitoimintaa ja teleteknillistä kehitystä ulkomailla. Luvussa käsitellään länsivaltojen kehityspiirteistä viestijoukkojen tehtäviä ja organisaatiota, viestijoukkojen koulutusta sekä kokeilu- ja tutkimustoimintaa. Seuraavaksi tarkastellaan teleteknistä kehitystä eri maissa, ottaen käsittelyyn radiotekniikan, suuntaradiotekniikan, televisiotoiminnan, puhelintekniikan ja vahvavirtatoiminnan. Luvun taulukossa on esitetty tietoja Sveitsin armeijan radiokalustosta. Viimeisessä luvussa tarkastellaan edellä todetun jaottelun mukaisesti teletekniikan ja vahvavirtatoiminnan kehitystä kotimaassa. Yhdistelmässä muun muassa todetaan, että "Viestiteollisuutemme on voimistunut jonkin verran, ja riippuvuus ulkomaisista raaka-aineista ja puolivalmisteista on vähentynyt ..."

Membrane attachment of Slr0006 in Synechocystis sp PCC 6803 is determined by divalent ions

Slr0006 is one of the Synechocystis sp. PCC 6803 proteins strongly induced under carbon limiting conditions. Slr0006 has no predicted transmembrane helices or signal peptide sequence, yet it was exclusively recovered in the membrane fraction of Synechocystis, when the cells were broken in isolation buffers which contain divalent cations and are generally used for photosynthesis studies. Even subsequent washing of the membranes with high salt or various detergents did not release Slr0006, indicating strong binding of the Slr0006 protein to the membranes. Further, DNAse or RNAse treatment did not disturb the tight binding of Slr0006 protein to the membranes. Nevertheless, when the cells were broken in the absence of divalent cations, Slr0006 remained completely soluble. Binding of the Slr0006 to the membrane could not be properly reconstituted if the cations were added after breaking the cells in the absence of divalent ions. This unusual phenomenon has to be considered in identification and localization of other yet uncharacterized cyanobacterial proteins