A candidate super-Earth planet orbiting near the snow line of Barnard's star.

Barnard's star is a red dwarf, and has the largest proper motion (apparent motion across the sky) of all known stars. At a distance of 1.8 parsecs1, it is the closest single star to the Sun; only the three stars in the α Centauri system are closer. Barnard's star is also among the least magnetically active red dwarfs known2,3 and has an estimated age older than the Solar System. Its properties make it a prime target for planetary searches; various techniques with different sensitivity limits have been used previously, including radial-velocity imaging4-6, astrometry7,8 and direct imaging9, but all ultimately led to negative or null results. Here we combine numerous measurements from high-precision radial-velocity instruments, revealing the presence of a low-amplitude periodic signal with a period of 233 days. Independent photometric and spectroscopic monitoring, as well as an analysis of instrumental systematic effects, suggest that this signal is best explained as arising from a planetary companion. The candidate planet around Barnard's star is a cold super-Earth, with a minimum mass of 3.2 times that of Earth, orbiting near its snow line (the minimum distance from the star at which volatile compounds could condense). The combination of all radial-velocity datasets spanning 20 years of measurements additionally reveals a long-term modulation that could arise from a stellar magnetic-activity cycle or from a more distant planetary object. Because of its proximity to the Sun, the candidate planet has a maximum angular separation of 220 milliarcseconds from Barnard's star, making it an excellent target for direct imaging and astrometric observations in the future.

Evidence of Incoherent Carriers Associated with Resonant Impurity Levels and Their Influence on Superconductivity in the Anomalous Superconductor Pb_{1-x}Tl_{x}Te.

We present a combined experimental and theoretical study of the evolution of the Fermi surface of the anomalous superconductor Pb_{1-x}Tl_{x}Te as a function of thallium concentration, drawing on a combination of magnetotransport measurements (Shubnikov-de Haas oscillations and the Hall coefficient), angle resolved photoemission spectroscopy, and density functional theory calculations of the electronic structure. Our results indicate that for Tl concentrations beyond a critical value, the Fermi energy coincides with resonant impurity states in Pb_{1-x}Tl_{x}Te, and we rule out the presence of an additional valence band maximum at the Fermi energy. A comparison to nonsuperconducting Pb_{1-x}Na_{x}Te implies that the presence of these impurity states at the Fermi energy provides the enhanced pairing interaction and thus also the anomalously high temperature superconductivity in this material.

[A scaphoid fracture overlooked in CT in a combination injury of the wrist]. / Im CT übersehene Kahnbeinfraktur bei Kombinationsverletzung des Handgelenks.

A case of a patient with a combined wrist injury is presented, where a scaphoid fracture was overlooked in the computed tomography scan. The case emphasizes the value of the x­ray control in ulnar abduction for all wrist lesions which need to be operatively stabilized.

Polymorphism of vitamin D3 receptor and its relation to mineral bone density in perimenopausal women.

UNLABELLED: Postmenopausal osteoporosis is the most common metabolic bone disease with important genetic factors. We evaluated the frequency of polymorphism 283G/A of the vitamin D3 VDR gene receptor. The study included 800 women at the postmenopausal (505) and reproductive (295) age. Statistically significant changes, depending on the genotype, were shown. INTRODUCTION: Postmenopausal osteoporosis is the most common metabolic bone disease of strong genetic origin with population variability determined by the interaction of genetic and environmental factors. Recognition of different genetic variants underlying development of osteoporosis would make it possible to administer individual symptomatic treatment as well as early prophylactics of osteoporosis. METHODS: The aim of the study was to evaluate the frequency of polymorphism 283G/A of the vitamin D3 VDR gene receptor and assessment of its relations with the clinical parameters of osseous turnover and degree of postmenopausal osteoporosis. The study included 800 women at the postmenopausal (505) and reproductive (295) age throughout the Wielkopolska region in Poland. The postmenopausal group included women with osteoporosis and osteopenia and the healthy ones. Women at the reproductive age were healthy. Frequency of the tested gene polymorphism was evaluated in the group where bone mineral density (BMD) was marked and in the control group. RESULTS: The obtained test results pointed to correlation of polymorphism VDR 283G/A with the BMD scores for the lumbar vertebrae in women with osteopenia and osteoporosis, therefore the ones at risk of fractures. Vitamin D receptor (VDR) polymorphism correlated with reduced BMD values. CONCLUSIONS: Polymorphism 283G/A of the vitamin D3 receptor gene has been proved to be the genetic factor of postmenopausal osteoporosis. The polymorphism mentioned above has been proved to be a factor of mineral bone density changes of women.

[SKF-index as an indicator of biological age of hemostasis and blood vessels in children and adults in norm and pathology].

A novel noninvasive method of an assessment of the hemostasis system and the vascular walls functioning is proposed. This method is based on the methodology of dynamic light scattering (DLS). New index SKF, which is derived from the previously established relationship between the intravascular mobility of the erythrocytes and the biological age, has been introduced. We demonstrated that the degree of the severity of the diseases correlates with the SKF index. More specifically, an increased value of the SKF index was found for the groups with cardio-vascular, oncological diseases and diabetes mellitus. In addition we provided evidences that the SKF index depends on the blood and plasma viscosity related to activity stage of the hemostasis system as well as on the functioning of the vascular walls.

Ba(1-x)K(x)Mn2As2: an antiferromagnetic local-moment metal.

The compound BaMn2As2 with the tetragonal ThCr2Si2 structure is a local-moment antiferromagnetic insulator with a Néel temperature T(N)=625 K and a large ordered moment µ=3.9µ(B)/Mn. We demonstrate that this compound can be driven metallic by partial substitution of Ba by K while retaining the same crystal and antiferromagnetic structures together with nearly the same high T(N) and large µ. Ba(1-x)K(x)Mn2As2 is thus the first metallic ThCr2Si2-type MAs-based system containing local 3d transition metal M magnetic moments, with consequences for the ongoing debate about the local-moment versus itinerant pictures of the FeAs-based superconductors and parent compounds. The Ba(1-x)K(x)Mn2As2 class of compounds also forms a bridge between the layered iron pnictides and cuprates and may be useful to test theories of high T(c) superconductivity.

Development of Poland's Central Bone Marrow Donor Registry Affects Donor Searches for Patients With Hematological Diseases.

In the last 10 years, numbers of donors in the case of Polish potential unrelated hematopoietic stem cells (HSC) have increased dynamically, reaching 1,900,000 in 2020 (including donors presented in World Marrow Donor Association as PL6). On the world scale, the share of Polish donors in the global registry increased from 1% in 2010 to about 5% in 2020. The level and range of typing of potential donors has also been improving steadily toward the international "gold standard." At the end of 2020, 92% of Polish resources were at least HLA-A, B, C, DR, DQ high- or intermediate-resolution typed, mostly by way of genomic typing techniques, mostly by way of genomic typing techniques. The Central Bone Marrow Donor Registry (CBMDR) also stands out in terms of the young ages of potential donors. As of 2020, 27.2% of those registered were younger than 30 years of age, and 36.3% were aged between 30 and 40 years. Sixty percent of registered donors were female. The data in question were presented at the World Marrow Donor Association Search & Match Service, ensuring their visibility and accessibility to Polish and international search units and registries. In 2020, donors in Poland were the subject of almost 18,000 search requests from 40 countries, with 271 extended typing requests and more than 7600 confirmatory typing requests. The total number of donations from Polish donors also increased. In 2020, HSC of bone marrow, peripheral blood, or lymphocytes were collected from 1391 donors, as opposed to 94 donors in 2010. The growing number of donors available in the CBMDR means a better chance of a donor being found among Polish resources, without any need to resort to international registers. Although in 2010, just 24% of Polish recipients received HSC from Polish donors, by 2019 the figure was as high as 67%, and reached 63% in 2020. The CBMDR is an example of proper strategy on registry development being implemented in Poland.

Cardiac stem cell therapy. Registered trials and a pilot study in patients with dilated cardiomyopathy.

In cardiac stem cell therapy, the past decade has been interesting with respect to preclinical and clinical research. The high diversity of applied stem cell populations and evaluation methods represent a challenge to fully understand the impact of stem cell administration, leaving uncertain answers to the questions that have been dealt with thus far. In the present work, registered studies in cardiac stem cell therapy are summarized and the study aims are highlighted. Furthermore, preliminary data on the additional intramyocardial administration of CD133+ stem cells in patients undergoing mitral valve surgery are presented.

Three-dimensional high-resolution anorectal manometry in children after surgery for anorectal disorders.

OBJECTIVE: Three-dimensional high-resolution anorectal manometry (3DHRAM) is the most precise tool for assessing the function of the anal canal. Our aim was to evaluate children after surgery for anorectal disorders using 3DHRAM. PATIENTS AND METHODS: We prospectively enrolled 43 children (30 males; mean age: 7 years) after surgery for Hirschsprung's disease, anal atresia, or after proctocolectomy. Manometric data were compared to raw data obtained from previously studied children without symptoms arising from the lower gastrointestinal tract. Correlations between manometry and symptoms were evaluated. RESULTS: The lowest values of the resting pressure, squeeze pressure, and pressure of the puborectalis muscle were observed in the anal atresia group (55.6 mmHg, 121.7 mmHg, and 44.17 mmHg, respectively). Compared to asymptomatic children, the lowest mean resting pressures were observed in those with non-retentive fecal incontinence (61.3 mmHg, p<0.000). The receiver operating curve cut-off value for the mean resting pressure between asymptomatic children and incontinent patients was 68.5 mmHg. The thresholds of urge were significantly higher in constipated patients compared to asymptomatic patients (87.5 cm³ and 30 cm³, respectively; p=0.003). CONCLUSIONS: 3DHRAM may be a useful tool for assessing the function of the anorectum of children after surgery (NCT02296008).

A nearby transiting rocky exoplanet that is suitable for atmospheric investigation.

Spectroscopy of transiting exoplanets can be used to investigate their atmospheric properties and habitability. Combining radial velocity (RV) and transit data provides additional information on exoplanet physical properties. We detect a transiting rocky planet with an orbital period of 1.467 days around the nearby red dwarf star Gliese 486. The planet Gliese 486 b is 2.81 Earth masses and 1.31 Earth radii, with uncertainties of 5%, as determined from RV data and photometric light curves. The host star is at a distance of ~8.1 parsecs, has a J-band magnitude of ~7.2, and is observable from both hemispheres of Earth. On the basis of these properties and the planet's short orbital period and high equilibrium temperature, we show that this terrestrial planet is suitable for emission and transit spectroscopy.

Anomalies in the Fermi surface and band dispersion of quasi-one-dimensional CuO chains in the high-temperature superconductor YBa2Cu4O8.

We have investigated the electronic states in quasi-one-dimensional CuO chains by microprobe angle resolved photoemission spectroscopy. We find that the quasiparticle Fermi surface consists of six disconnected segments, consistent with recent theoretical calculations that predict the formation of narrow, elongated Fermi surface pockets for coupled CuO chains. In addition, we find a strong renormalization effect with a significant kink structure in the band dispersion. The properties of this latter effect [energy scale (∼40 meV), temperature dependence, and behavior with Zn-doping] are identical to those of the bosonic mode observed in CuO2 planes of high-temperature superconductors, indicating they have a common origin.

Comparison of mouse, rat and rabbit models for adipose - Derived stem cells (ASC) research.

PURPOSE OF THE STUDY: Cellular therapies are becoming more popular and there is a big demand for suitable animal model for research in field of tissue engineering. Both the small (rodents) and large animals have their advantages for cellular therapy experiments. Appropriate animal research model would be a bridge between basic research and clinical medicine. The aim of this study was to compare mouse, rat and rabbit as animal models useful for adipose - derived stem cell research. MATERIALS AND METHODS: Quantity, phenotype, clonogenic and differentiation potential of cells isolated from different localizations of adipose tissue from WAG and LEW/W rat strains, rabbit and mouse were analysed. RESULTS: The highest number of cells from 1 g of tissue were isolated from cervical white fat of LEW/W rat. ASCs isolated from rat had also the highest clonogenic potential. Phenotype and capability to differentiate into osteogenic, adipogenic and chondrogenic lineages are at the same level for rat and rabbit. CONCLUSIONS: Rat as a research model can be a rational solution between large animal models and typical laboratory mice because of their size, genetic homogenity, availability of genetically modified stains and possibility to perform research mimicking clinical applications.

High Layer Uniformity of Two-Dimensional Materials Demonstrated Surprisingly from Broad Features in Surface Electron Diffraction.

Paradoxically, a very broad diffraction background, named the bell-shaped-component (BSC), has been established as a feature of graphene growth. Recent diffraction studies as a function of electron energy have shown that the BSC is not related to scattering interference. Here, additional experiments are carried out as a function of temperature over the range in which single-layer graphene (SLG) grows. Quantitative fitting of the profiles shows that the BSC follows the increase of the Gr(10) spot, proving directly that the BSC indicates high-quality graphene. Additional metal deposition experiments provide more information about the BSC. The BSC is insensitive to metal deposition, and it increases with metal intercalation, because a more uniform interface forms between graphene and SiC. These experiments support the conclusion that the BSC originates from electron confinement within SLG, and surprisingly, it is an excellent measure of graphene uniformity.

Quality System of Kidney Donation for Transplantation From Living Donors in Poland.

OBJECTIVE: The program aims to build and develop a high-quality donation system at the hospital and national level. Thirty coordinator posts for the transplantation of kidneys from living donors (LDs) were created. The coordinators' tasks were identified as determining or excluding the possibility of LD donation for kidney transplantation for every potential kidney recipient referred to the waiting list, qualifying potential LDs, supervising health monitoring for LDs and kidney recipients, and education and promotion of transplantation from LDs. METHODS: The coordinators' reports and verification of data in the national transplant register from June 1, 2018 to November 30, 2019 were analyzed. ETHICS: The study was conducted according to principles of the Declaration of Helsinki, and the Declaration of Istanbul participation was on a voluntary basis. RESULTS: Information on possible LDs was obtained from 707 (43%) of the 1630 potential recipients entered on the waiting list. In 373 cases there was no potential LD; 16 recipients did not give consent for kidney transplantation from a LD; for 318 recipients, 340 potential LDs were identified; 90 potential LDs were rejected at the initial stage for medical reasons; 60 potential donors were rejected at further stages of the qualification process; 3 persons resigned from donation; and 23 recipients were transplanted from deceased donors. Kidneys from 73 LDs were qualified and transplanted. On November 30, 2019, 91 potential donors were awaiting further qualification. As part of the program, 27 potential pairs for paired kidney exchange were reported to Poltransplant (17 pairs with positive HLA crossmatch, 10 with incompatible blood groups). CONCLUSIONS: The creation of posts for coordinators for LD kidney transplantation in centers that qualify for LD kidney transplantation enabled systematic monitoring of donation potential, which led to an increase in the number of LD kidney transplants in 2019. Making full use of donation potential should significantly increase these numbers in the coming years.

New Treatment of Wound Healing With Allogenic Acellular Human Skin Graft: Preclinical Assessment and In Vitro Study.

BACKGROUND: Nonhealing wounds can be a major clinical problem. Impaired wound healing is often related to massive tissue injury, concomitant wound healing deficiencies (chronic wounds), burn injury, or congenital conditions. We propose a novel biological dressing as an alternative surgical approach. The dressing is a form of an allogenic human skin graft equivalent with further use of allogeneic stem cells classified as an advanced therapy medicinal product. This new allogenic acellular human skin graft has been specifically developed to address the clinical indications for dressing wound lesions and promoting tissue repair in specific rare genetic diseases. METHODS: This case report illustrates the use of an acellular human skin allograft seeded with multipotent stem cells in the treatment of tissue injuries (burns), congenital conditions, and chronic wounds. Donor-tissue processing yields an acellular dermal matrix with integral collagen bundling and organization, as well as an intact basement membrane complex. RESULTS: Preclinical observations show prolonged viability of acellular human skin grafts with multipotent stem cells. This was confirmed with histological and electron-microscopic evaluation of biopsies, which demonstrated host-cell infiltration and neovascularization of the biological dressing. Moreover, the dressings were characterized by low immunogenicity, as confirmed by histology exam and T-cell proliferation assays in vitro. CONCLUSION: Our data confirmed the safety and efficacy of the evaluated acellular human skin grafts, which may be used in patients with rare diseases, such as epidermolysis bullosa, burn injuries, and chronic wounds.

Transplantation of a New Biological Product in Rare Diseases, Such as Epidermolysis Bullosa: Response and Clinical Outcome.

BACKGROUND: Epidermolysis bullosa (EB) is a phenotypically diverse group of hereditary blistering disorders involving mutations in 20 different genes. Those debilitating disorders are currently incurable; however, there are a number of promising preclinical trials, where some treatments already approach the stage of early clinical trial. In this paper we introduce a novel surgical approach to the treatment of EB-induced ulcerations. The purpose of our study was to evaluate the safety and efficacy of a new biological dressing in the form of an allogenic human skin equivalent graft before using multipotent stem cells, classified as an advanced therapy medicinal product. METHODS: Implanted human acellular dermal matrices were prepared from the superficial layers of donated human skin. Scaffold sterilization was conducted via irradiation with the use of a linear electron accelerator. Following water-knife debridement, wounds were surgically covered with accordingly prepared grafts and dressed in burn-injury fashion. Subsequently, the wounds were monitored for infection and viability. RESULTS: Our data indicate that grafting as a potential new medicinal product was safe and effective in patients with rare diseases, such as EB, and may be used for stem cells to create new Advanced Therapy Medicinal Products. During a 200-day follow-up, we proved the safety of using human scaffolds (allogeneic graft) by observing no apparent infection or necrosis. Instead, we noted fewer required dressing changes, promoted wound healing, pain reduction, and an overall improvement in the quality of life in patients with EB. CONCLUSION: The protocol for grafting allogenic acellular epidermal sheets is the most promising treatment for severely affected skin areas in EB patients to date.

Mechanical properties of radiation-sterilised human Bone-Tendon-Bone grafts preserved by different methods.

Patellar tendon auto- and allo-grafts are commonly used in orthopedic surgery for reconstruction of the anterior cruciate ligaments (ACL). Autografts are mainly used for primary reconstruction, while allografts are useful for revision surgery. To avoid the risk of infectious disease transmission allografts should be radiation-sterilised. As radiation-sterilisation supposedly decreases the mechanical strength of tendon it is important to establish methods of allograft preservation and sterilisation assuring the best quality of grafts and their safety at the same time. Therefore, the purpose of this study was to compare the tensile strength of human patellar tendon (cut out as for ACL reconstruction), preserved by various methods (deep fresh freezing, glycerolisation, lyophilisation) and subsequently radiation-sterilised with doses of 0, 25, 50 or 100 kGy. Bone-Tendon-Bone grafts (BTB) were prepared from cadaveric human patella tendons with both patellar and tibial attachments. BTB grafts were preserved by deep freezing, glycerolisation or lyophilisation and were subsequently radiation-sterilised with doses of 0 (control), 25, 50 or 100 kGy. All samples were subjected to mechanical failure tensile tests with the use of Instron system in order to estimate their mechanical properties. All lyophilised grafts were rehydrated before performing of those tests. Obtained mechanical tests results of examined grafts suggest that deep-frozen irradiated grafts retain their initial mechanical properties to an extent which does not exclude their clinical application.

The novel mechanism of initiation of picornavirus RNA translation.

The initiation of translation of picornaviral RNAs takes place by an unusual mechanism whereby ribosomes bind directly to an internal site rather than scan the RNA from the 5'-end. This internal entry mechanism requires a 450-nucleotide segment of the picornavirus 5'-untranslated region. The ribosome binds initially to a site at the 3'-end of this segment, and then may scan the RNA to reach the authentic initiation site. This novel mechanism may be of relevance to the translation of some cellular mRNAs.

Changes in spatio-temporal localization of tripeptidyl peptidase II (TPPII) in murine colon adenocarcinoma cells during aggresome formation: a microscopy study based on a novel fluorescent proteasome inhibitor.

Extralysosomal proteolysis is a multistep process involving the Ubiquitin- Proteasome System (UPS) and supplementary peptidases. Tripeptidyl peptidase II (TPPII) is the most extensively characterized enzyme, supplementing and sometimes substituting for proteasomal functions. In response to proteasome inhibition, polyubiquitinated proteins acting as proteasome substrates aggregate with proteasomes and form aggresomes. Several proteasome inhibitors are used as anti-cancer drugs. Thus, in our study, we used a novel fluorescent-tagged proteasome inhibitor BSc2118 to induce aggresome formation in C26 murine colon adenocarcinoma cells. It allowed us to obtain effective, inhibitor-based, proteasome staining in vivo. This method has been validated by standard post-fixed indirect immunostaining and also allowed co-immunodetection of TPPII and polyubiquitinated proteins under laser scanning confocal microscopy. We found that in the absence of the inhibitor, TPPII is diffusely dispersed within the cytoplasm of C26 cells. The proteasome and ubiquitin-rich perinuclear region failed to display enhanced TPPII staining. However, when proteasome function was impaired by the inhibitor, TPPII associated more closely with both the proteasome and polyubiquitinated proteins via TPPII recruitment to the perinuclear region and subsequently into emerging aggresomal structures. Furthermore, we have demonstrated the dynamic recruitment of TPPII into the developing aggresome: TPPII in the early aggresome was dispersed within the central part but subsequently aggregated on the surface of this structure. In the mature aggresome of C26 cells TPPII formed a spherical mantle, which surrounded the round core containing proteasomes and polyubiquitinated proteins. Our morphological data indicate that TPPII displays spatial localization with proteasomes especially upon proteasome inhibition in aggresomes of C26 cells.

Evaluation of six commercial products for colistin susceptibility testing in Enterobacterales.

OBJECTIVES: The recommended technique for colistin susceptibility testing by both EUCAST and CLSI is broth microdilution (BMD). However, many routine laboratories still use other methods such as gradient strips or semi-automated systems. The objective of this study was to compare six of the most widespread commercial products for colistin susceptibility testing in Europe with in-house prepared BMD. METHODS: A collection of 325 carbapenemase-producing Enterobacterales was tested for colistin susceptibility with three semi-automated systems (Vitek 2, BD Phoenix, MicroScan WalkAway), one gradient-strip test (Etest®) and two commercial BMD products (MICRONAUT-S, TREK Sensititre). BMD, in-house prepared according to ISO standard 20776-1, served as reference. RESULTS: The MICRONAUT-S BMD performed best with only one false-resistant (major error, ME) and four false-susceptible (very major error, VME) results while the TREK BMD performed poorer with 16 ME and seven VME. The semi-automated systems Vitek 2 and Phoenix performed poorly with 31 and 26 VME, respectively. The WalkAway semi-automated system showed 16 and 13 false results, depending on the inoculation method. The Etest® showed six ME and 10 VME. CONCLUSIONS: This study shows that colistin susceptibility testing remains a challenging task for laboratories. It emphasizes the need for selecting the most reliable test method to advocate proper treatment and shows that critical evaluation and precautious usage of colistin susceptibility testing results is constantly required.