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It is still not fully elucidated which pretransplant donor-specific HLA antibodies (DSA) are harmful after kidney transplantation. In particular, it needs to be clarified whether cumulative mean fluorescence intensities (MFI) against multiple HLA specificities have a predictive value for allograft function. Our retrospective single centre study analyzed preformed HLA antibodies determined by Luminex™ Single Antigen Bead (SAB) assay, including C1q addition, in relation to rejection and clinical outcome in 255 cross match negative kidney allograft recipients. Only 33 recipients (13%) of the total cohort showed early AMR during the first year posttransplant, but in patients with pre-transplant DSA the rate was increased to 15 out of 40 (38%). Three year graft survival was significantly shorter in patients with histological signs of AMR compared with patients without AMR or with no biopsy (74%, 92%, and 97%, respectively, p

Journals have begun to publish papers in which chatbots such as ChatGPT are shown as co-authors. The following WAME recommendations are intended to inform editors and help them develop policies regarding chatbots for their journals, to help authors understand how use of chatbots might be attributed in their work, and address the need for all journal editors to have access manuscript screening tools. In this rapidly evolving field, we expect these recommendations to evolve as well.

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The evolution and progress in cardiovascular medicine and substantial changes in the German health care system require both a reflection of the principles of patient-centered care in general and an update of the criteria that define a department of cardiac surgery in Germany. This position paper lists the core requirements for a cardiac surgical department with regard to infrastructure, facilities, necessary staff, and standard of care (processes). This standard may be used by hospitals and health care providers to ensure the safety and quality of cardiac surgical departments in Germany.

For documentation of COVID-19 pandemic-related changes in cardiac surgery in Germany, the German Society for Thoracic and Cardiovascular Surgery carried out a structured survey.From 79 German institutions for cardiac surgery, 53 took part in the survey. The cut-off date before the pandemic was taken as 1 January 2020 and 30 April 2021 as the cut-off date for data recruitment. At this point of time, the third wave of the pandemic in Germany had already ebbed away and the return to routine surgery seemed to be foreseeable.On 1 January 2020, in 53 German cardiac surgery departments 800 intensive care beds were allocated. In April 2021, this capacity was reduced by 25.6% to 595 beds. Accordingly, the number of operating rooms for cardiac surgery procedures was reduced from 207 to 152 (-26.9%) during the first two lockdowns. During the COVID-19 pandemic, hospital facilities were restructured: 50.9% of participants delegated medical personnel, and 75.5% had to transfer nursing personnel to special COVID-19 facilities in their hospitals.From the start of the COVID-19 pandemic until the end of the third wave during April 2021, cardiac surgery in Germany changed profoundly, leading to a substantial reduction of intensive care beds and operating rooms for patients requiring cardiac surgery.

BackgroundAntibody-mediated rejection (ABMR) is the main cause of renal allograft loss. The most common treatment strategy is based on plasmapheresis plus the subsequent administration of intravenous immunoglobulin (IVIG). Unfortunately, no approved long-term therapy is available for ABMR. The current study was designed to analyze the effect of various ABMR treatment approaches on allograft survival and to compare treatment effects in the presence or absence of donor-specific antibodies (DSAs).MethodsThis single-center study retrospectively analyzed 102 renal allograft recipients who had biopsy-proven ABMR after transplant. DSA was detectable in 61 of the 102 patients. Initial standard treatment of ABMR consisted of plasmapheresis (PS) or immunoadsorption (IA), followed by a single course of IVIG. In case of nonresponse or recurrence, additional immunosuppressive medications, such as rituximab, bortezomib, thymoglobulin, or eculizumab, were administered. In a second step, persistent ABMR was treated with increased maintenance immunosuppression, long-term therapy with IVIG (more than 1 year), or both.ResultsOverall graft survival among transplant patients with ABMR was p = 0.83). Remarkably, allografts survival rates were comparable between patients treated with the combination of PS/IA and IVIG and those treated with a single administration of IVIG (p = 0.18). Renal transplant patients with ABMR but without DSAs benefited more from increased maintenance immunosuppression than did DSA-positive patients with ABMR (p = 0.01). Recipients with DSA-positive ABMR exhibited significantly better allograft survival after long-term application of IVIG for more than 1 year than did recipients with DSA-negative ABMR (p = 0.02).ConclusionsThe results of our single-center cohort study involving kidney transplant recipients with ABMR suggest that long-term application of IVIG is more favorable for DSA-positive recipients, whereas intensification of maintenance immunosuppression is more effective for recipients with DSA-negative ABMR.

With the introduction of the virtual allocation crossmatch in the Eurotransplant (ET) region in 2023, the determination of unacceptable antigen mismatches (UAM) in kidney transplant recipients is of utmost importance for histocompatibility laboratories and transplant centers. Therefore, a joined working group of members from the German Society for Immunogenetics (Deutsche Gesellschaft für Immungenetik, DGI) and the German Transplantation Society (Deutsche Transplantationsgesellschaft, DTG) revised and updated the previous recommendations from 2015 in light of recently published evidence. Like in the previous version, a wide range of topics is covered from technical issues to clinical risk factors. This review summarizes the evidence about the prognostic value of contemporary methods for HLA antibody detection and identification, as well as the impact of UAM on waiting time, on which these recommendations are based. As no clear criteria could be determined to differentiate potentially harmful from harmless HLA antibodies, the general recommendation is to assign all HLA against which plausible antibodies are found as UAM. There is, however, a need for individualized solutions for highly immunized patients. These revised recommendations provide a list of aspects that need to be considered when assigning UAM to enable a fair and comprehensible procedure and to harmonize risk stratification prior to kidney transplantation between transplant centers.

CA extern BACKGROUND: Morbidity and mortality rates are high for patients returning to dialysis after renal graft failure. Keeping failed kidney transplants in situ with concomitant minimization or withdrawal of immunosuppression is standard of care in many transplant centers. It is unclear, however, whether the resulting allospecific immune response can cause a microinflammatory milieu. The present work investigated the impact of allograft nephrectomy on systemic inflammation, erythropoiesis, and donor-specific antibodies (DSA). MATERIAL AND METHODS: We performed a retrospective analysis evaluating C-reactive protein (CRP), hemoglobin concentration (Hb), ferritin, iron substitution dosages, erythropoietin dosages, and DSA in 92 transplant recipients with allograft failure, of whom 49 did not (Group A) and 43 did undergo transplant nephrectomy (Group B). Blood samples and clinical data were obtained 3-6 months after returning to dialysis. We additionally assessed outcome of kidney re-transplantation in a 10-year follow-up. RESULTS: There was no significant difference in Hb concentrations, ferritin concentrations, CRP concentrations, iron, and EPO substitution dosages between the 2 groups. Patients undergoing nephrectomy had a significantly higher prevalence of DSA (65.1% vs 38.8%, P

Sodium–oxygen cells with sodium superoxide (NaO2) as discharge product show charge and discharge characteristics with very low overvoltage, different from lithium/oxygen cells. Here, it is shown that the discharge of a nonaqueous sodium/oxygen cell proceeds via the electrochemical formation of superoxide (O2–), its dissolution in the liquid electrolyte, and subsequent precipitation together with sodium ions as solid sodium superoxide. Charge proceeds in the counter-direction by consumption of dissolved superoxide anions and dissolution of NaO2. Indirect evidence for the solution-precipitation route is provided by theoretical results on the electronic structure of NaO2 and the conclusion that the electronic conductivity of NaO2 is too low to allow direct electrochemical growth and dissolution. Direct evidence for the solution-precipitation route is provided by results from charge/discharge studies of a three-electrode cell in which preformed NaO2 is being decomposed without direct electronic contact to the...

We present density functional theory (DFT) calculations on phonon dispersions, phonon density of states, and thermodynamic quantities for the three copper oxide phases ${\mathrm{Cu}}_{2}\mathrm{O},{\mathrm{Cu}}_{4}{\mathrm{O}}_{3}$, and CuO. For monoclinic CuO we consider the correct antiferromagnetic ground state. Sound velocities for the acoustic phonon branches and Debye temperatures are calculated and are found to be in good agreement with experiment. We further show how the method for the treatment of dipole-dipole interactions in dynamical matrices of Gonze and Lee [Phys. Rev. B 55, 10355 (1997)] may be incorporated in the real-space (direct) method for interatomic force constants (FCs). The role of the long-ranged dipole-dipole interactions in the phonon dispersion is discussed. Based on this method, we outline a perturbationlike scheme to compute first-order derivatives of the phonon mode frequencies with respect to the wave vector which can be used to compute velocities of sound.

We analyze the influence of the Mg concentration on several important properties of the band structure of Zn1-xMgxO alloys in wurtzite structure using ab initio calculations. For this purpose, the band structure for finite concentrations is defined in terms of the Bloch spectral density, which can be calculated within the coherent potential approximation. We investigate the concentration dependence of the band gap and the crystal-field splitting of the valence bands. The effective electron and hole masses are determined by extending the effective mass model to finite concentrations. We compare our results with experimental results and other calculations.

The Luminex-based human leukocyte antigen (HLA) antibody screening technology is widespread used in laboratories affiliated to kidney transplantation programs and enables both screening (i.e. the definition of positive or negative antibody status) and antibody identification with high sensitivity and specificity. HLA typing at different levels of resolution with Luminex technology uses sequence-specific oligonucleotide probes bound to color-coded microbeads in order to identify HLA alleles encoded by the DNA sample. In general, the Luminex technology for histocompatibility analyses provides rapid sample processing in a 96-well format combined with limited technical complexity which means high cost efficiency.

The Raman spectrum of crystalline $\mathrm{Cu}{}_{2}\mathrm{O}$ taken off resonance is reproducible and independent of the growth method and conditions employed. But, in contrast to most other crystalline materials, the Raman spectrum of $\mathrm{Cu}{}_{2}\mathrm{O}$ is dominated by infrared active and silent lattice modes rather than by the only Raman allowed phonon mode. We show that this unusual behavior is most likely caused by the presence of copper vacancies in the so-called split configuration, a point defect particular to $\mathrm{Cu}{}_{2}\mathrm{O}$. The reduction of symmetry due to the presence of point defects may lift the Raman selection rules and may introduce Raman activity for phonon modes that are Raman forbidden in the case of perfect crystal symmetry. Based on this group theoretical consideration, we predict the angle dependence of the Raman intensities of all $\mathrm{Cu}{}_{2}\mathrm{O}$ one-phonon modes at $k=0$ for rotation about the (100) direction caused by the presence of various intrinsic point defects. Of all intrinsic defects in question, only the presence of the copper vacancy in the split configuration introduces Raman activity for all $\mathrm{Cu}{}_{2}\mathrm{O}$ extended phonon modes observed in experiment and is consistent with the angle-dependent measurements. Our study underlines the special role of the split vacancy in $\mathrm{Cu}{}_{2}\mathrm{O}$.

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A novel growth phase-associated two-component-type regulator, Fas (fibronectin/fibrinogen binding/haemolytic activity/streptokinase regulator), of Streptococcus pyogenes was identified in the M1 genome sequence, based on homologies to the histidine protein kinase (HPK) and response regulator (RR) part of the Staphylococcus aureus Agr and Streptococcus pneumoniae Com quorum-sensing systems. The fas operon, present in all 12 tested M serotypes, was transcribed as polycystronic message (fasBCA) and contained genes encoding two potential HPKs (FasB and FasC) and one RR (FasA). Downstream of fasBCA, we identified a small 300 nucleotide monocistronic transcript, designated fasX, that did not appear to encode true peptide sequences. Measurements of luciferase promoter fusions revealed a growth phase-associated transcription of fasBCA and fasX, with peak activities during the late exponential phase. Insertional mutagenesis disrupting fasBCA and fasA led to a phenotype similar to agr-null mutations in S. aureus, with prolonged expression of extracellular matrix protein-binding adhesins and reduced expression of secreted virulence factors such as streptokinase and streptolysin S. In addition, fasX transcription was dependent on the RR FasA; however, deletion mutagenesis of fasX resulted in a similar phenotype to that of the fasBCA or fasA mutants. Complementation of the fasX deletion mutant, with the fasX gene expressed in trans from a plasmid, restored the wild-type fasBCA regulation pattern. This strongly suggested that fasX, a putative non-translated RNA, is the main effector molecule of the fas regulon. However, using spent culture supernatants from wild-type and fas mutant strains, we were not able to show an influence on the logarithmic growth phase expression of fas and dependent genes. Thus, despite structural and functional similarities between fas and agr, to date the fas operon appears not to be involved in group A streptococcal (GAS) quorum-sensing regulation.

We describe a procedure to eliminate contaminating Mycoplasma from Chlamydia pneumoniae (C. pneumoniae) cultures by pulmonary passage in severe combined immunodeficiency mice (SCID). Four weeks after experimental infection only C. pneumoniae could be cultured from the lungs of the infected animals while Mycoplasma could not be detected any longer, as shown by PCR, culture and transmission electron microscopy (TEM).

Chlamydia pneumoniae is an intracellular respiratory pathogen, which, similar to Legionella, might have developed mechanisms to escape the intracellular bactericidal activity of both human host cells and amoeba. We therefore investigated the intracellular growth and survival of C. pneumoniae in Acanthamoeba castellanii by using cell culture, immunofluorescence microscopy, and electron microscopy. A castellanii was incubated with purified elementary bodies of C. pneumoniae TW 183 at a concentration of 10(6) inclusion-forming units (IFU)/ml to give a ratio of approximately 1 IFU of C. pneumoniae per amoeba. Quantitative determination of chlamydial growth within A. castellanii revealed viable and infective C. pneumoniae in the range of 10(4) to 10(5) IFU/ml between days 7 and 14 postinfection. Immunofluorescence analysis and transmission electron microscopy with subsequent immunogold staining confirmed evidence of infection of the amoebae by C. Pneumoniae and additionally revealed that C. pneumoniae entered the typical growth cycle. Our results show that amoebae allow the survival of C. pneumoniae, suggesting that amoebae may serve as an additional reservoir for Chlamydia or Chlamydia-related organisms.

The $p$-type semiconductor copper oxide has three distinct phases Cu${}_{2}$O, CuO, and Cu${}_{4}$O${}_{3}$ with different morphologies and oxidation states of the copper ions. We investigate the structural stability and electronic band structure of all three copper oxide compounds using ab initio methods within the framework of density functional theory and consider different exchange correlation functionals. While the local density approximation (LDA) fails to describe the semiconducting states of CuO and Cu${}_{4}$O${}_{3}$, the $\mathrm{LDA}+U$ and HSE06 hybrid functional describe both compounds as indirect semiconductors. Using the HSE06 hybrid functional we calculate the electronic band structure in the full Brillouin zone for all three copper oxide compounds.

The physics of cuprous oxide (Cu2O) is reviewed with respect to structural, optical, and electrical properties. New experimental findings are included especially in the context of theoretical band-structure calculations. Intrinsic defects related to nonstoichiometry are made responsible for the p-type conduction. First preliminary experiments on the alloying of Cu2O by sulfur are reported.

We investigate direct electron-electron-hole interband Auger recombination for wurtzite Zn(1-x)Mg(x)O alloys in the range 0

Cardiac myxomas are the most frequently encountered benign intracardiac tumors, that, if left untreated, are inexorably progressive and potentially fatal. Patients with cardiac myxoma can be treated only by surgical removal. This study summarizes our experience over 22 years with these tumors.Fifty seven patients (M/F: 14/43, age: 57.9 +/- 14.6 years) with cardiac myxomas underwent surgical resection at our institution. There were 82.4% left atrial myxomas, 14.0% right atrial myxomas, 3.6% biatrial myxomas. The duration of symptoms prior to surgery ranged from 6 to 1,373 days (median 96 days). The surgical approach comprised complete wide excision. The diagnostic methods, incidence of thromboembolic complications, valve degeneration, surgical repair techniques, recurrence and re-operation were reviewed and the Kaplan-Meier survival curve was calculated.There were no in-hospital deaths. Hospital stay amounted to a mean of 13.7 +/- 6.9 days. Late follow-up was available for 54 (94.7%) patients for a median 7.5 years after surgery (23 days to 21.4 years). Fifty two patients are alive, while five patients had died after a mean interval of 6.3 years. Cause of death was cardiac in 40% of the patients (n = 2) and non-cardiac in the other 60% (n = 3).Surgical excision of cardiac myxoma carries a low operative risk and gives excellent short-term and long-term results. Surgical excision of the tumor appears to be curative, with few recurrences at long-term follow-up. After diagnosis, surgery should be performed urgently, in order to prevent complications such as embolic events or obstruction of the mitral orifice. Follow-up examination, including echocardiography, should be performed regularly.

We perform density functional theory calculations to determine equilibrium lattice parameters of wurtzite Zn1-xMgxO alloys for Mg concentrationsxranging from 0 to 31.25 %. We use the local density approximation (LDA) as well as the generalized gradient approximation (GGA) for the exchange correlation functional. For the lattice constants a and c we find a deviation from Vegard's law and a constant unit cell volume independent of the Mg concentration.

Cardiac papillary fibroelastoma (CPF) is a rare primary benign cardiac tumor. Before the use of echocardiography, the lesion was identified at autopsy or incidentally during cardiac surgery. CPF is the third most common primary cardiac tumor after atrial myxoma and lipoma, and is the most common tumor of the valvular endothelium. Transthoracic echocardiography (TTE) and transesophageal echocardiography (TEE) permit diagnosis of the tumor in living patients. CPF may be the cause of cerebrovascular or cardiac ischemia due to embolization or occlusion of the vascular ostia. Embolic material may arise from fragments of the tumor itself, or from surrounding thrombus. The case is reported of a patient with CPF of the aortic valve in whom TEE diagnosis was conducted and the tumor removed surgically.

Three cases of life-threatening C. pneumoniae infection in patients with acute leukemia and treatment-induced neutropenia are described. Diagnosis was made on the basis of the detection of C. pneumoniae-DNA, complemented by serology. The role of the widely distributed respiratory tract pathogen C. pneumoniae in febrile neutropenia is poorly understood, and studies are needed to estimate the frequency of severe pulmonary infection caused by this agent in patients with neutropenia.

Chlamydia pneumoniae was able to survive and to multiply in the human monocytic cell line Mono Mac 6. Growth of C. pneumoniae induced production of tumor necrosis factor alpha, interleukin 1beta, and interleukin 6, as well as up-regulation of the CD14 molecule in a time-dependent manner. Infection of monocytic cells and a proinflammatory cytokine response may be important in C. pneumoniae pathogenesis.

We developed a new model of human genital Chlamydia trachomatis infection in order to characterize the pathogen-host relationship in a clinically relevant system using a human strain of C. trachomatis instead of the commonly employed mouse biovar (MoPn). Human endometrial tissue was xenografted into the skin of mice homozygous for the mutation severe combined immunodeficiency and inoculated with C. trachomatis serovar K. C. trachomatis efficiently infected the endometrium as shown by cell culture and immunofluorescence microscopy and persisted for more than 6 weeks. Chlamydial inclusions detected by direct immunofluorescence and electron microscopy appeared to be smaller than those produced by in vitro cell culture-grown chlamydiae. A pattern of localized mild infection prevailed, and infiltrative uncontrolled spread of chlamydiae was observed in only 1 of 10 infected grafts. This might correspond to the well-known tendency of the agent to cause asymptomatic infections. This model allows the study of a human genital infection resembling the clinical situation and offers the possibility to better characterize the host-parasite relationship with respect to pathogenicity and therapy.