Soluble Cyanobacterial Carotenoprotein as a Robust Antioxidant Nanocarrier and Delivery Module

To counteract oxidative stress, antioxidants including carotenoids are highly promising, yet their exploitation is drastically limited by the poor bioavailability and fast photodestruction, whereas current delivery systems are far from being efficient. Here we demonstrate that the recently discovered nanometer-sized water-soluble carotenoprotein from Anabaena sp. PCC 7120 (termed AnaCTDH) transiently interacts with liposomes to efficiently extract carotenoids via carotenoid-mediated homodimerization, yielding violet–purple protein samples. We characterize the spectroscopic properties of the obtained pigment–protein complexes and the thermodynamics of liposome–protein carotenoid transfer and demonstrate the delivery of carotenoid echinenone from AnaCTDH into liposomes with an efficiency of up to 70 ± 3%. Most importantly, we show efficient carotenoid delivery to membranes of mammalian cells, which provides protection from reactive oxygen species (ROS). Incubation of neuroblastoma cell line Tet21N in the presence of 1 μM AnaCTDH binding echinenone decreased antimycin A ROS production by 25% (p < 0.05). The described carotenoprotein may be considered as part of modular systems for the targeted antioxidant delivery.BMBF, 01DJ15007, Carotenoidbindende photoschaltbare Proteine: Lichtinduzierte Dynamik und Anwendungen in modernen mikroskopischen Verfahre

Correlation between Nafion Morphology in Various Dispersion Liquids and Properties of the Cast Membranes

Nafion is a perfluorosulfonic acid polymer that is most commonly used in proton-exchange membrane fuel cells. The processes of pretreatment and formation of such membranes strongly affect their properties. In this work, dispersions of Nafion in various ionic forms and dispersing liquids (ethylene glycol, N,N-dimethylformamide, N-methyl-2-pyrrolidone and isopropyl alcohol–water mixtures in different ratios) were obtained and studied. Membranes fabricated by casting of the various dispersions were also studied. The effect of the nature of the dispersing liquid and the counterion on the properties of Nafion dispersions, the morphology of the polymer in the dispersions and the characteristics of the membranes obtained from them has been shown. Based on the overall results, it can be concluded that the use of perfluorosulfonic acid dispersions in aprotic polar solvents is advisable for obtaining membranes by the casting procedure. This is because it provides optimal polymer morphology in the dispersion, which leads to the formation of films with good selectivity, mechanical and transport properties. The performed investigations show the relationship between the composition of dispersions, the morphology of the polymer and the properties of the membranes formed from them by the casting procedure

Perfluorosulfonic Acid Membranes with Short and Long Side Chains and Their Use in Sensors for the Determination of Markers of Viral Diseases in Saliva

The development of accessible express methods to determine markers of viral diseases in saliva is currently an actual problem. Novel cross-sensitive sensors based on Donnan potential with bio-comparable perfluorosulfonic acid membranes for the determination of salivary viral markers (N-acetyl-L-methionine, L-carnitine, and L-lysine) were proposed. Membranes were formed by casting from dispersions of Nafion or Aquivion in N-methyl-2-pyrollidone or in a mixture of isopropyl alcohol and water. The influence of the polymer equivalent weight and the nature of dispersing liquid on water uptake, ion conductivity, and slope of Donnan potential for the membranes in H+ and Na+ form was investigated. The varying of the sorption and transport properties of perfluorosulfonic acid membranes provided a change in the distribution of the sensor sensitivity to N-acetyl-L-methionine, L-carnitine, and L-lysine ions, which was necessary for multisensory system development. The simultaneous determination of three analytes, and the group analysis of them in artificial saliva solutions, was performed. The errors of N-acetyl-L-methionine and L-carnitine determination were 4–12 and 3–11%, respectively. The determination of L-lysine was complicated by its interaction with Ca2+ ions. The error of the group analysis was no greater than 9%. The reverse character of the viral markers’ sorption by the membranes provided long-term sensor operation

Methanospirillum stamsii sp. nov., a psychrotolerant, hydrogenotrophic, methanogenic archaeon isolated from an anaerobic expanded granular sludge bed bioreactor operated at low temperature

A psychrotolerant hydrogenotrophic methanogen, strain Pt1, was isolated from a syntrophic propionate-oxidizing methanogenic consortium obtained from granulated biomass of a two-stage low-temperature (3–8 °C) anaerobic expanded granular sludge bed (EGSB) bioreactor, fed with a mixture of volatile fatty acids (VFAs) (acetate, propionate and butyrate). The strain was strictly anaerobic, and cells were curved rods, 0.4–0.5×7.5–25 µm, that sometimes formed wavy filaments from 25 to several hundred micrometres in length. Cells stained Gram-negative and were non-sporulating. They were gently motile by means of tufted flagella. The strain grew at 5–37 °C (optimum at 20–30 °C), at pH 6.0–10 (optimum 7.0–7.5) and with 0–0.3 M NaCl (optimum 0 M NaCl). Growth and methane production was found with H2/CO2 and very weak growth with formate. Acetate and yeast extract stimulated growth, but were not essential. The G+C content of the DNA of strain Pt1 was 40 mol%. Phylogenetic analysis based on 16S rRNA gene sequences revealed that strain Pt1 was a member of the genus Methanospirillum and showed 97.5 % sequence similarity to Methanospirillum hungatei JF1T and 94 % sequence similarity to Methanospirillum lacunae Ki8-1T. DNA–DNA hybridization of strain Pt1 with Methanospirillum hungatei JF1T revealed 39 % relatedness. On the basis of its phenotypic characteristics and phylogenetic position, strain Pt1 is a representative of a novel species of the genus Methanospirillum , for which the name Methanospirillum stamsii sp. nov. is proposed. The type strain is Pt1T ( = DSM 26304T = VKM B-2808T)

COVID-19-related mortality in kidney transplant and dialysis patients: Results of the ERACODA collaboration

Background. Patients on kidney replacement therapy comprise a vulnerable population and may be at increased risk of death from coronavirus disease 2019 (COVID-19). Currently, only limited data are available on outcomes in this patient population. Methods. We set up the ERACODA (European Renal Association COVID-19 Database) database, which is specifically designed to prospectively collect detailed data on kidney transplant and dialysis patients with COVID-19. For this analysis, patients were included who presented between 1 February and 1 May 2020 and had complete information available on the primary outcome parameter, 28-day mortality. Results. Of the 1073 patients enrolled, 305 (28%) were kidney transplant and 768 (72%) dialysis patients with a mean age of 60 6 13 and 67 6 14 years, respectively. The 28-day probability of death was 21.3% [95% confidence interval (95% CI) 14.3\u201330.2%] in kidney transplant and 25.0% (95% CI 20.2\u201330.0%) in dialysis patients. Mortality was primarily associated with advanced age in kidney transplant patients, and with age and frailty in dialysis patients. After adjusting for sex, age and frailty, in-hospital mortality did not significantly differ between transplant and dialysis patients [hazard ratio (HR) 0.81, 95% CI 0.59\u20131.10, P \ubc 0.18]. In the subset of dialysis patients who were a candidate for transplantation (n \ubc 148), 8 patients died within 28 days, as compared with 7 deaths in 23 patients who underwent a kidney transplantation &lt;1 year before presentation (HR adjusted for sex, age and frailty 0.20, 95% CI 0.07\u20130.56, P &lt; 0.01). Conclusions. The 28-day case-fatality rate is high in patients on kidney replacement therapy with COVID-19 and is primarily driven by the risk factors age and frailty. Furthermore, in the first year after kidney transplantation, patients may be at increased risk of COVID-19-related mortality as compared with dialysis patients on the waiting list for transplantation. This information is important in guiding clinical decision-making, and for informing the public and healthcare authorities on the COVID-19-related mortality risk in kidney transplant and dialysis patients

Recovery of dialysis patients with COVID-19: health outcomes 3 months after diagnosis in ERACODA

© The Author(s) 2022.Background. Coronavirus disease 2019 (COVID-19)-related short-term mortality is high in dialysis patients, but longer-term outcomes are largely unknown. We therefore assessed patient recovery in a large cohort of dialysis patients 3 months after their COVID-19 diagnosis. Methods. We analyzed data on dialysis patients diagnosed with COVID-19 from 1 February 2020 to 31 March 2021 from the European Renal Association COVID-19 Database (ERACODA). The outcomes studied were patient survival, residence and functional and mental health status (estimated by their treating physician) 3 months after COVID-19 diagnosis. Complete follow-up data were available for 854 surviving patients. Patient characteristics associated with recovery were analyzed using logistic regression. Results. In 2449 hemodialysis patients (mean ± SD age 67.5 ± 14.4 years, 62% male), survival probabilities at 3 months after COVID-19 diagnosis were 90% for nonhospitalized patients (n = 1087), 73% for patients admitted to the hospital but not to an intensive care unit (ICU) (n = 1165) and 40% for those admitted to an ICU (n = 197). Patient survival hardly decreased between 28 days and 3 months after COVID-19 diagnosis. At 3 months, 87% functioned at their pre-existent functional and 94% at their pre-existent mental level. Only few of the surviving patients were still admitted to the hospital (0.8–6.3%) or a nursing home (∼5%). A higher age and frailty score at presentation and ICU admission were associated with worse functional outcome. Conclusions. Mortality between 28 days and 3 months after COVID-19 diagnosis was low and the majority of patients who survived COVID-19 recovered to their pre-existent functional and mental health level at 3 months after diagnosis

Clinical, Functional, and Mental Health Outcomes in Kidney Transplant Recipients 3 Months after a Diagnosis of COVID-19

Background. Kidney transplant patients are at high risk for coronavirus disease 2019 (COVID-19)-related mortality. However, limited data are available on longer-term clinical, functional, and mental health outcomes in patients who survive COVID-19. Methods. We analyzed data from adult kidney transplant patients in the European Renal Association COVID-19 Database who presented with COVID-19 between February 1, 2020, and January 31, 2021. Results. We included 912 patients with a mean age of 56.7 (±13.7) y. 26.4% were not hospitalized, 57.5% were hospitalized without need for intensive care unit (ICU) admission, and 16.1% were hospitalized and admitted to the ICU. At 3 mo follow-up survival was 82.3% overall, and 98.8%, 84.2%, and 49.0%, respectively, in each group. At 3 mo follow-up biopsy-proven acute rejection, need for renal replacement therapy, and graft failure occurred in the overall group in 0.8%, 2.6%, and 1.8% respectively, and in 2.1%, 10.6%, and 10.6% of ICU-admitted patients, respectively. Of the surviving patients, 83.3% and 94.4% reached their pre-COVID-19 physician-reported functional and mental health status, respectively, within 3 mo. Of patients who had not yet reached their prior functional and mental health status, their treating physicians expected that 79.6% and 80.0%, respectively, still would do so within the coming year. ICU admission was independently associated with a low likelihood to reach prior functional and mental health status. Conclusions. In kidney transplant recipients alive at 3-mo follow-up, clinical, physician-reported functional, and mental health recovery was good for both nonhospitalized and hospitalized patients. Recovery was, however, less favorable for patients who had been admitted to the ICU

Sex differences in COVID-19 mortality risk in patients on kidney function replacement therapy

In the general population with COVID-19, the male sex is an established risk factor for mortality, in part due to a more robust immune response to COVID-19 in women. Because patients on kidney function replacement therapy (KFRT) have an impaired immune response, especially kidney transplant recipients due to their use of immunosuppressants, we examined whether the male sex is still a risk factor for mortality among patients on KFRT with COVID-19. From the European Renal Association COVID-19 Database (ERACODA), we examined patients on KFRT with COVID-19 who presented between February 1st, 2020, and April 30th, 2021. 1204 kidney transplant recipients (male 62.0%, mean age 56.4 years) and 3206 dialysis patients (male 61.8%, mean age 67.7 years) were examined. Three-month mortality in kidney transplant recipients was 16.9% in males and 18.6% in females (p = 0.31) and in dialysis patients 27.1% in males and 21.9% in females (p = 0.001). The adjusted HR for the risk of 3-month mortality in males (vs females) was 0.89 (95% CI 65, 1.23, p = 0.49) in kidney transplant recipients and 1.33 (95% CI 1.13, 1.56, p = 0.001) in dialysis patients (pinteraction = 0.02). In a fully adjusted model, the aHR for the risk of 3-month mortality in kidney transplant recipients (vs. dialysis patients) was 1.39 (95% CI 1.02, 1.89, p = 0.04) in males and 2.04 (95% CI 1.40, 2.97, p < 0.001) in females (pinteraction = 0.02). In patients on KFRT with COVID-19, the male sex is not a risk factor for mortality among kidney transplant recipients but remains a risk factor among dialysis patients. The use of immunosuppressants in kidney transplant recipients, among other factors, may have narrowed the difference in the immune response to COVID-19 between men and women, and therefore reduced the sex difference in COVID-19 mortality risk

Association of obesity with 3-month mortality in kidney failure patients with COVID-19

Background: In the general population with coronavirus disease 2019 (COVID-19), obesity is associated with an increased risk of mortality. Given the typically observed obesity paradox among patients on kidney function replacement therapy (KFRT), especially dialysis patients, we examined the association of obesity with mortality among dialysis patients or living with a kidney transplant with COVID-19. Methods: Data from the European Renal Association COVID-19 Database (ERACODA) were used. KFRT patients diagnosed with COVID-19 between 1 February 2020 and 31 January 2021 were included. The association of Quetelet's body mass index (BMI) (kg/m2), divided into: <18.5 (lean), 18.5-24.9 (normal weight), 25-29.9 (overweight), 30-34.9 (obese I) and ≥35 (obese II/III), with 3-month mortality was investigated using Cox proportional-hazards regression analyses. Results: In 3160 patients on KFRT (mean age: 65 years, male: 61%), 99 patients were lean, 1151 normal weight (reference), 1160 overweight, 525 obese I and 225 obese II/III. During follow-up of 3 months, 28, 20, 21, 23 and 27% of patients died in these categories, respectively. In the fully adjusted model, the hazard ratios (HRs) for 3-month mortality were 1.65 [95% confidence interval (CI): 1.10, 2.47], 1 (ref.), 1.07 (95% CI: 0.89, 1.28), 1.17 (95% CI: 0.93, 1.46) and 1.71 (95% CI: 1.27, 2.30), respectively. Results were similar among dialysis patients (N = 2343) and among those living with a kidney transplant (N = 817) (Pinteraction = 0.99), but differed by sex (Pinteraction = 0.019). In males, the HRs for the association of aforementioned BMI categories with 3-month mortality were 2.07 (95% CI: 1.22, 3.52), 1 (ref.), 0.97 (95% CI: 0.78. 1.21), 0.99 (95% CI: 0.74, 1.33) and 1.22 (95% CI: 0.78, 1.91), respectively, and in females corresponding HRs were 1.34 (95% CI: 0.70, 2.57), 1 (ref.), 1.31 (95% CI: 0.94, 1.85), 1.54 (95% CI: 1.05, 2.26) and 2.49 (95% CI: 1.62, 3.84), respectively. Conclusion: In KFRT patients with COVID-19, on dialysis or a kidney transplant, obesity is associated with an increased risk of mortality at 3 months. This is in contrast to the obesity paradox generally observed in dialysis patients. Additional studies are required to corroborate the sex difference in the association of obesity with mortality