In Vitro Analysis of the Thyroid Hormone Receptor in Mitochondrial Transcription

The central dogma theory relates how DNA is transcribed into messenger RNA (mRNAs) and then translated into proteins. Since the nucleus contains the majority of the DNA in cells, research related to transcription and translation focuses on these processes within the nucleus and cytosol; however, these processes are also taking place within the mitochondrial organelle. Mitochondria are most widely known for their essential role in producing energy for the cell, but the organelle also contains its own small, circular genome. Transcription of mitochondrial DNA (mtDNA) follows similar mechanisms as does transcription of nuclear DNA. During this essential process, specific mitochondrial transcription factors, such as TFAM and TFB2M, regulate the attachment of the mitochondrial RNA polymerase (POLRMT) to the promoter and initiation of transcription. With a fully functioning mitochondrial RNA polymerase, transcription is properly conducted, and transcripts can be translated to protein by the mitochondrial ribosome. Mitochondrial transcription is a major regulatory process within the organelle, and determining transcription factors involved in this control point is important for understanding mitochondrial function and many diseases relating to mitochondrial dysfunction. Numerous transcription factors are found both in the nucleus as well as in the mitochondria where their function is not well understood. One such transcription factor is the thyroid hormone receptor. Previous research suggests that when the hormone triiodothyronine (T3) is present and taken up in cells, mitochondrial transcription increases. The mechanism behind the T3 stimulation of transcription is thought to be a coordinated effect by interacting with both the mitochondrial and nuclear thyroid hormone receptor. Our aim is to analyze the level of interaction that the mitochondrial thyroid hormone receptor (mt-TRalpha1) has with the mitochondrial DNA and other core mitochondrial transcription factors in the presence and absence of the T3 hormone. With this information, we further understand another component of mitochondrial transcription that could have implications in mitochondrial dysfunction and disease

Under & Over: A randomised controlled study to develop an upper limb rehabilitation tool for people with Multiple Sclerosis.

BACKGROUND: Impairment of upper limb function is common in Multiple Sclerosis (MS). Rehabilitation remains a key strategy to manage symptoms and improve quality of life. The Under & Over study assessed the effectiveness of a rehabilitation programme in people with advanced MS. OBJECTIVE: To determine if repeated use of Under & Over can improve upper limb function for people with MS. METHODS: One hundred and six (N = 106) people with MS participated in this 3-month study. The primary outcome measure was the cardboard 9-hole peg test (c9HPT), with secondary outcomes including the EuroQol-5Dimensions, 5-Level Questionnaire (EQ5D-5 L) questionnaire. There were three arms: Arm 1a, the 'Daily Group', engaged with the Under & Over tool daily for 30 min. Arm 1b, the 'Free Use Group', used the same tool without time constraints, with the added feature of a community sharing platform. Arm 2, the 'Delayed Start Group', initially completed the c9HPT for three months before switching to the 'Free Use' programme. RESULTS: 43/106 (41 %) of those randomised completed the primary end point. No significant difference between c9HPT at baseline and 3 months was seen in Arm 1a or 1b. Participants in Arm 2 who had been completing the c9HPT 5 days a week for 3 months showed a training effect in the dominant hand (mean speed at baseline 0.0455 (s-1), mean at 3 months 0.0341, difference 0.011; 95 % CI 0.0080 to 0.0148, p < 0.001). No significant difference was seen in c9HPT time following 3 months of active use of the Under & Over tool. The study faced significant limitations, notably in participant adherence, with fewer than half (43/106 (41 %)) completing the final assessment. CONCLUSIONS: This study demonstrates how a small, engaged, and motivated group were able to complete a remote rehabilitation programme. Future remote intervention studies could benefit from incorporating adaptive engagement strategies, such as personalised reminders and participant-tailored activity adjustments, to enhance adherence and capture a broader spectrum of patient experiences

Non-immortalized human tenocyte cultures as a vehicle for understanding cellular aspects to tendinopathy

The biochemical mechanisms underlying tendinopathy are obscure. We briefly describe preliminary observations of human tenocyte behaviour in culture as a vehicle for determining the role of reactive oxygen in tendon patholog

Unconventional Josephson Effect in Hybrid Superconductor-Topological Insulator Devices

We report on transport properties of Josephson junctions in hybrid superconducting-topological insulator devices, which show two striking departures from the common Josephson junction behavior: a characteristic energy that scales inversely with the width of the junction, and a low characteristic magnetic field for suppressing supercurrent. To explain these effects, we propose a phenomenological model which expands on the existing theory for topological insulator Josephson junctions

Pet191 Is a Cytochrome c Oxidase Assembly Factor in \u3ci\u3eSaccharomyces cerevisiae\u3c/i\u3e

The twin-Cx9C motif protein Pet191 is essential for cytochrome c oxidase maturation. The motif Cys residues are functionally important and appear to be present in disulfide linkages within a large oligomeric complex associated with the mitochondrial inner membrane. The import of Pet191 differs from that of other twin-Cx9C motif class of proteins in being independent of the Mia40 pathway

Three-dimensional dental microwear in type-Maastrichtian mosasaur teeth (Reptilia, Squamata)

Mosasaurs (Squamata, Mosasauridae) were large aquatic reptiles from the Late Cretaceous that filled a range of ecological niches within marine ecosystems. The type-Maastrichtian strata (68–66 Ma) of the Netherlands and Belgium preserve remains of five species that seemed to have performed different ecological roles (carnivores, piscivores, durophages). However, many interpretations of mosasaur diet and niche partitioning are based on qualitative types of evidence that are difficult to test explicitly. Here, we apply three-dimensional dental microwear texture analysis (DMTA) to provide quantitative dietary constraints for type-Maastrichtian mosasaurs, and to assess levels of niche partitioning between taxa. DMTA indicates that these mosasaurs did not exhibit neatly defined diets or strict dietary partitioning. Instead, we identify three broad groups: (i) mosasaurs Carinodens belgicus and Plioplatecarpus marshi plotting in the space of modern reptiles that are predominantly piscivorous and/or consume harder invertebrate prey, (ii) Prognathodon saturator and Prognathodon sectorius overlapping with extant reptiles that consume larger amounts of softer invertebrate prey items, and (iii) Mosasaurus hoffmanni spanning a larger plot area in terms of dietary constraints. The clear divide between the aforementioned first two groups in texture-dietary space indicates that, despite our small sample sizes, this method shows the potential of DMTA to test hypotheses and provide quantitative constraints on mosasaur diets and ecological roles

Three-dimensional dental microwear in type-Maastrichtian mosasaur teeth (Reptilia, Squamata)

Mosasaurs (Squamata, Mosasauridae) were large aquatic reptiles from the Late Cretaceous that filled a range of ecological niches within marine ecosystems. The type-Maastrichtian strata (68–66 Ma) of the Netherlands and Belgium preserve remains of five species that seemed to have performed different ecological roles (carnivores, piscivores, durophages). However, many interpretations of mosasaur diet and niche partitioning are based on qualitative types of evidence that are difficult to test explicitly. Here, we apply three-dimensional dental microwear texture analysis (DMTA) to provide quantitative dietary constraints for type-Maastrichtian mosasaurs, and to assess levels of niche partitioning between taxa. DMTA indicates that these mosasaurs did not exhibit neatly defined diets or strict dietary partitioning. Instead, we identify three broad groups: (i) mosasaurs Carinodens belgicus and Plioplatecarpus marshi plotting in the space of modern reptiles that are predominantly piscivorous and/or consume harder invertebrate prey, (ii) Prognathodon saturator and Prognathodon sectorius overlapping with extant reptiles that consume larger amounts of softer invertebrate prey items, and (iii) Mosasaurus hoffmanni spanning a larger plot area in terms of dietary constraints. The clear divide between the aforementioned first two groups in texture-dietary space indicates that, despite our small sample sizes, this method shows the potential of DMTA to test hypotheses and provide quantitative constraints on mosasaur diets and ecological roles

Resonant magneto-optic Kerr effect in the magnetic topological insulator Cr:(Sbx_x,Bi1−x_{1-x})2_2Te3_3

We report measurements of the polar Kerr effect, proportional to the out-of-plane component of the magnetization, in thin films of the magnetically doped topological insulator $(\text{Cr}_{0.12}\text{Bi}_{0.26}\text{Sb}_{0.62})_2\text{Te}_3$. Measurements of the complex Kerr angle, $\Theta_K$, were performed as a function of photon energy in the range $0.8\text{ eV}<\hbar\omega<3.0\text{ eV}$. We observed a peak in the real part of $\Theta_K(\omega)$ and zero crossing in the imaginary part that we attribute to resonant interaction with a spin-orbit avoided crossing located $\approx$ 1.6 eV above the Fermi energy. The resonant enhancement allows measurement of the temperature and magnetic field dependence of $\Theta_K$ in the ultrathin film limit, $d\geq2$ quintuple layers. We find a sharp transition to zero remanent magnetization at 6 K for $d<8$~QL, consistent with theories of the dependence of impurity spin interactions on film thickness and their location relative to topological insulator surfaces.Comment: 6 pages, 5 figure