Proteomic and transcriptomic profiling of brainstem, cerebellum and olfactory tissues in early- and late-phase COVID-19.

Neurological symptoms, including cognitive impairment and fatigue, can occur in both the acute infection phase of coronavirus disease 2019 (COVID-19) and at later stages, yet the mechanisms that contribute to this remain unclear. Here we profiled single-nucleus transcriptomes and proteomes of brainstem tissue from deceased individuals at various stages of COVID-19. We detected an inflammatory type I interferon response in acute COVID-19 cases, which resolves in the late disease phase. Integrating single-nucleus RNA sequencing and spatial transcriptomics, we could localize two patterns of reaction to severe systemic inflammation, one neuronal with a direct focus on cranial nerve nuclei and a separate diffuse pattern affecting the whole brainstem. The latter reflects a bystander effect of the respiratory infection that spreads throughout the vascular unit and alters the transcriptional state of mainly oligodendrocytes, microglia and astrocytes, while alterations of the brainstem nuclei could reflect the connection of the immune system and the central nervous system via, for example, the vagus nerve. Our results indicate that even without persistence of severe acute respiratory syndrome coronavirus 2 in the central nervous system, local immune reactions are prevailing, potentially causing functional disturbances that contribute to neurological complications of COVID-19.

The neurobiology of SARS-CoV-2 infection.

Worldwide, over 694 million people have been infected with SARS-CoV-2, with an estimated 55-60% of those infected developing COVID-19. Since the beginning of the pandemic in December 2019, different variants of concern have appeared and continue to occur. With the emergence of different variants, an increasing rate of vaccination and previous infections, the acute neurological symptomatology of COVID-19 changed. Moreover, 10-45% of individuals with a history of SARS-CoV-2 infection experience symptoms even 3 months after disease onset, a condition that has been defined as 'post-COVID-19' by the World Health Organization and that occurs independently of the virus variant. The pathomechanisms of COVID-19-related neurological complaints have become clearer during the past 3 years. To date, there is no overt - that is, truly convincing - evidence for SARS-CoV-2 particles in the brain. In this Review, we put special emphasis on discussing the  methodological difficulties of viral detection in CNS tissue and discuss immune-based (systemic and central) effects contributing to COVID-19-related CNS affection. We sequentially review the reported changes to CNS cells in COVID-19, starting with the blood-brain barrier and blood-cerebrospinal fluid barrier - as systemic factors from the periphery appear to primarily influence barriers and conduits - before we describe changes in brain parenchymal cells, including microglia, astrocytes, neurons and oligodendrocytes as well as cerebral lymphocytes. These findings are critical to understanding CNS affection in acute COVID-19 and post-COVID-19 in order to translate these findings into treatment options, which are still very limited.

Three dimensional computed tomography texture analysis of pulmonary lesions: Does radiomics allow differentiation between carcinoma, neuroendocrine tumor and organizing pneumonia?

PURPOSE: To investigate whether CT texture analysis allows differentiation between adenocarcinomas, squamous cell carcinomas, carcinoids, small cell lung cancers and organizing pneumonia and between carcinomas and neuroendocrine tumors. METHOD: This retrospective study included patients 133 patients (30 patients with organizing pneumonia, 30 patients with adenocarcinoma, 30 patients with squamous cell carcinoma, 23 patients with small cell lung cancer, 20 patients with carcinoid), who underwent CT-guided biopsy of the lung and had a corresponding histopathologic diagnosis. Pulmonary lesions were segmented in consensus by two radiologists with and without a threshold of -50HU in three dimensions. Groupwise comparisons were performed to assess for differences between all five above-listed entities and between carcinomas and neuroendocrine tumors. RESULTS: Pairwise comparisons of the five entities revealed 53 statistically significant texture features when using no HU-threshold and 6 statistically significant features with a threshold of -50HU. The largest AUC (0.818 [95%CI 0.706-0.930]) was found for the feature wavelet-HHH_glszm_SmallAreaEmphasis for discrimination of carcinoid from the other entities when using no HU-threshold. In differentiating neuroendocrine tumors from carcinomas, 173 parameters proved statistically significant when using no HU threshold versus 52 parameters when using a -50HU-threshold. The largest AUC (0.810 [95%CI 0.728-0,893]) was found for the parameter original_glcm_Correlation for discrimination of neuroendocrine tumors from carcinomas when using no HU-threshold. CONCLUSIONS: CT texture analysis revealed features that differed significantly between malignant pulmonary lesions and organizing pneumonia and between carcinomas and neuroendocrine tumors of the lung. Applying a HU-threshold for segmentation substantially influenced the results of texture analysis.

Hypertrophic Pachymeningitis with Persistent Intrathecal Inflammation Secondary to Neurosarcoidosis Treated with Intraventricular Chemotherapy: A Case Report.

Hypertrophic pachymeningitis (HP) is a rare immune-mediated disease characterized by thickening of the dura mater with consecutive cranial neuropathy. While HP is usually treated with systemic immunotherapies, response to therapy is variable and may be limited by insufficient drug concentrations in the brain. We report on a 57-year-old patient with HP manifesting with vision and hearing loss who had sustained clinical progression despite various systemic immunotherapies. Intraventricular chemotherapy with methotrexate, cytarabine, and dexamethasone was initiated. We present clinical, imaging and cerebrospinal fluid (CSF) findings, including cytokine levels before and after intraventricular treatment: rapid decrease of cell count, lactate and profibrotic cytokine levels in the CSF following intraventricular chemotherapy was paralleled by a mild reduction of dura thickness in MRI. The already severely impaired visual acuity and hearing loss did not progress further. Treatment was complicated by exacerbation of previously subtle psychiatric symptoms. Follow-up was terminated after 6 months as the patient suffered from a fatal ischemic stroke. Autopsy revealed neurosarcoidosis as the underlying cause of HP. This case report suggests that intrathecal chemotherapy can reduce the inflammatory milieu in the CNS and should be considered for treatment-refractory HP before irreversible damage of cranial nerves has occurred.

A Conceptual Framework for Evaluating National Organ Donation and Transplantation Programs.

Conceptual frameworks are valuable resources that can be used to guide the planning, evaluation, and development of healthcare services. However, there are currently no comprehensive frameworks focused on organ donation and transplantation that identify the critical factors underlying a successful national program. To address this knowledge gap, we developed a conceptual framework that takes into account all major domains of influence, including political and societal aspects as well as clinical implementation. The framework was initially constructed based on a targeted review of the relevant medical literature. Feedback provided by a panel of international experts was incorporated into the framework via an iterative process. The final framework features 16 essential domains that are critical for initiating and maintaining a successful program and improving the health of patients with organ failure. Of particular note, these domains are subject to three overarching health system principles: responsiveness, efficiency, and equity. This framework represents a first attempt to develop a whole-system view of the various factors that contribute to the success of a national program. These findings provide a useful tool that can be adapted to any jurisdiction and used to plan, evaluate, and improve organ donation and transplantation programs.

Ten Lessons From the Spanish Model of Organ Donation and Transplantation.

The organ donation and transplantation program in Spain has long been considered the gold standard worldwide. An in-depth understanding of the Spanish program may promote the development and reform of transplant programs in other countries. Here, we present a narrative literature review of the Spanish organ donation and transplantation program supplemented by expert feedback and presented according to a conceptual framework of best practices in the field. Core features of the Spanish program include its three-tiered governing structure, close and collaborative relationships with the media, dedicated professional roles, a comprehensive reimbursement strategy, and intensive tailored training programs for all personnel. Several more sophisticated measures have also been implemented, including those focused on advanced donation after circulatory death (DCD) and expanded criteria for organ donation. The overall program is driven by a culture of research, innovation, and continuous commitment and complemented by successful strategies in prevention of end-stage liver and renal disease. Countries seeking ways to reform their current transplant systems might adopt core features and may ultimately aspire to include the aforementioned sophisticated measures. Countries intent on reforming their transplant system should also introduce programs that support living donation, an area of the Spanish program with potential for further improvement.

Lessons From the Portuguese Solid Organ Donation and Transplantation System: Achieving Success Despite Challenging Conditions.

Over the past two decades, Portugal has become one of the world leaders in organ donation and transplantation despite significant financial constraints. This study highlights how Portugal achieved success in organ donation and transplantation and discusses how this information might be used by other countries that are seeking to reform their national programs. To accomplish this goal, we performed a narrative review of relevant academic and grey literature and revised our results after consultation with two national experts. Our findings were then synthesized according to a conceptual framework for organ donation and transplantation programs. Our results revealed several key strategies used by the Portuguese organ donation and transplantation program, including collaboration with Spain and other European nations, a focus on tertiary prevention, and sustained financial commitment. This report also explores how cooperative efforts were facilitated by geographical, governmental, and cultural proximity to Spain, a world leader in organ donation and transplantation. In conclusion, our review of the Portuguese experience provides insight into the development of organ donation and transplantation systems. However, other countries seeking to reform their national transplant systems will need to adapt these policies and practices to align with their unique cultures and contexts.

Solid Organ Donation and Transplantation in the United Kingdom: Good Governance is Key to Success.

The United Kingdom (UK) supports a highly successful organ donation and transplantation program. While the UK originally had one of the lowest organ donation rates in Europe, sustained reforms have resulted in steady improvement. Of note, the UK nearly doubled its rate of deceased donations between 2008 and 2018. In this report, we present a case study of the UK organ donation and transplantation program as an example of a complete system with sound and inclusive governing structures that are strongly integrated with critical programs focused on training and research. This study was based on an initial targeted review of the literature led by a UK expert that included guidelines, national reports, and academic papers. Feedback solicited from other European experts was incorporated into our findings via an iterative process. Overall, the study highlights the stepwise evolution of the UK program that ultimately became successful largely due to ongoing collaborative efforts carried out at all levels. Centralized coordination of all aspects of the program remains a key driver of improved rates of organ donation and transplantation. The designation and empowerment of expert clinical leadership have helped to maintain focus and promote ongoing quality improvement.

The National Organ Donation and Transplantation Program in Greece: Gap Analysis and Recommendations for Change.

Greece has fallen far behind many comparable European countries in the field of organ donation and transplantation and has made little progress over the past decade. Despite efforts to improve its organ donation and transplantation program, systemic problems persist. In 2019, the Onassis Foundation commissioned a report to be prepared by the London School of Economics and Political Science that focused on the state of the Greek organ donation and transplantation program and proposed recommendations for its improvement. In this paper, we present our analysis of the Greek organ donation and transplantation program together with an overview of our specific recommendations. The analysis of the Greek program was undertaken in an iterative manner using a conceptual framework of best practices developed specifically for this project. Our findings were further developed via an iterative process with information provided by key Greek stakeholders and comparisons with case studies that featured successful donation and transplantation programs in Croatia, Italy, Portugal, Spain, and the United Kingdom. Because of their overall complexity, we used a systems-level approach to generate comprehensive and far-reaching recommendations to address the difficulties currently experienced by the Greek organ donation and transplantation program.

Organ Donation in Croatia: The Importance of a National Champion, a Comprehensive Plan, and International Collaborations.

The Republic of Croatia is a global leader in organ donation and transplantation despite having fewer resources and more modest healthcare expenditures than other countries in the European Union. The results of an extensive literature review were combined with expert input in an iterative multi-step data collection and evaluation process designed to assess trends in Croatian organ donation and transplantation and identify key elements, policy changes, and drivers of the system that have contributed to its success. Multiple sources of evidence were used in this study, including primary documents, national and international transplantation reports, and insights from critical informants and content experts. The results highlight several key organizational reforms that have substantially improved the performance of the Croatian transplant program. Our findings emphasize the importance of strong central governance led by an empowered national clinical leader acting under the direct auspices of the Ministry of Health and a comprehensive and progressive national plan. The Croatian transplant system is notable for its integrated approach and efficient manner of managing scarce health resources. Collectively, the results suggest that Croatia has become nearly self-sufficient due to its systematic implementation of the guiding principles for organ donation and transplantation.

How to Structure a Successful Organ Donation and Transplantation System in Eight (Not So Easy) Steps: An Italian Case Study.

Valuable information can be obtained from a systematic evaluation of a successful national transplant program. This paper provides an overview of Italy's solid organ transplantation program which is coordinated by the National Transplant Network (Rete Nazionale Trapianti) and The National Transplant Center (Centro Nazionale Trapianti). The analysis is based on a system-level conceptual framework and identifies components of the Italian system that have contributed to improving rates of organ donation and transplantation. A narrative literature review was conducted and the findings were validated iteratively with input from subject matter experts. The results were organized into eight critical steps, including 1) generating legal definitions of living and deceased donation, 2) taking steps to ensure that altruistic donation and transplantation become part of the national culture and a point of pride, 3) seeking out existing examples of successful programs, 4) creating a situation in which it is easy to become a donor, 5) learning from mistakes, 6) working to diminish risk factors that lead to the need for organ donation, 7) increasing the rate of donations and transplantations via innovative strategies and policies, and 8) planning for a system that supports growth.

The brain reacting to COVID-19: analysis of the cerebrospinal fluid proteome, RNA and inflammation.

Patients with COVID-19 can have a variety of neurological symptoms, but the active involvement of central nervous system (CNS) in COVID-19 remains unclear. While routine cerebrospinal fluid (CSF) analyses in patients with neurological manifestations of COVID-19 generally show no or only mild inflammation, more detailed data on inflammatory mediators in the CSF of patients with COVID-19 are scarce. We studied the inflammatory response in paired CSF and serum samples of patients with COVID-19 (n = 38). Patients with herpes simplex virus encephalitis (HSVE, n = 10) and patients with non-inflammatory, non-neurodegenerative neurological diseases (n = 28) served as controls. We used proteomics, enzyme-linked immunoassays, and semiquantitative cytokine arrays to characterize inflammatory proteins. Autoantibody screening was performed with cell-based assays and native tissue staining. RNA sequencing of long-non-coding RNA and circular RNA was done to study the transcriptome. Proteomics on single protein level and subsequent pathway analysis showed similar yet strongly attenuated inflammatory changes in the CSF of COVID-19 patients compared to HSVE patients with, e.g., downregulation of the apolipoproteins and extracellular matrix proteins. Protein upregulation of the complement system, the serpin proteins pathways, and other proteins including glycoproteins alpha-2 and alpha-1 acid. Importantly, calculation of interleukin-6, interleukin-16, and CXCL10 CSF/serum indices suggest that these inflammatory mediators reach the CSF from the systemic circulation, rather than being produced within the CNS. Antibody screening revealed no pathological levels of known neuronal autoantibodies. When stratifying COVID-19 patients into those with and without bacterial superinfection as indicated by elevated procalcitonin levels, inflammatory markers were significantly (p < 0.01) higher in those with bacterial superinfection. RNA sequencing in the CSF revealed 101 linear RNAs comprising messenger RNAs, and two circRNAs being significantly differentially expressed in COVID-19 than in non-neuroinflammatory controls and neurodegenerative patients. Our findings may explain the absence of signs of intrathecal inflammation upon routine CSF testing despite the presence of SARS-CoV2 infection-associated neurological symptoms. The relevance of blood-derived mediators of inflammation in the CSF for neurological COVID-19 and post-COVID-19 symptoms deserves further investigation.

In Vitro Examinations of Cell Death Induction and the Immune Phenotype of Cancer Cells Following Radiative-Based Hyperthermia with 915 MHz in Combination with Radiotherapy.

Multimodal tumor treatment settings consisting of radiotherapy and immunomodulating agents such as immune checkpoint inhibitors are more and more commonly applied in clinics. In this context, the immune phenotype of tumor cells has a major influence on the anti-tumor immune response as well as the composition of the tumor microenvironment. A promising approach to further boost anti-tumor immune responses is to add hyperthermia (HT), i.e., heating the tumor tissue between 39 °C to 45 °C for 60 min. One key technique is the use of radiative hyperthermia systems. However, knowledge is limited as to how the frequency of the used radiative systems affects the immune phenotype of the treated tumor cells. By using our self-designed in vitro hyperthermia system, we compared cell death induction and expression of immune checkpoint molecules (ICM) on the tumor cell surface of murine B16 melanoma and human MDA-MB-231 and MCF-7 breast cancer cells following HT treatment with clinically relevant microwaves at 915 MHz or 2.45 GHz alone, radiotherapy (RT; 2 × 5 Gy or 5 × 2 Gy) alone or in combination (RHT). At 44 °C, HT alone was the dominant cell death inductor with inactivation rates of around 70% for B16, 45% for MDA-MB-231 and 35% for MCF-7 at 915 MHz and 80%, 60% and 50% at 2.45 GHz, respectively. Additional RT resulted in 5-15% higher levels of dead cells. The expression of ICM on tumor cells showed time-, treatment-, cell line- and frequency-dependent effects and was highest for RHT. Computer simulations of an exemplary spherical cell revealed frequency-dependent local energy absorption. The frequency of hyperthermia systems is a newly identified parameter that could also affect the immune phenotype of tumor cells and consequently the immunogenicity of tumors.

COVID-19: Autopsy findings in six patients between 26 and 46 years of age.

OBJECTIVES: Studies on coronavirus disease 2019 (COVID-19) usually focus on middle-aged and older adults. However, younger patients may present with severe COVID-19 with potentially fatal outcomes. For optimized, more specialized therapeutic regimens in this particular patient group, a better understanding of the underlying pathomechanisms is of utmost importance. METHODS: Our study investigated relevant, pre-existing medical conditions, clinical histories, and autopsy findings, together with SARS-CoV-2-RNA, determined by qPCR, and laboratory data in six COVID-19 decedents aged 50 years or younger, who were autopsied at the Charité University Hospital. RESULTS: From a total of 76 COVID-19 patients who underwent an autopsy at our institution, six (7.9%) were 50 years old or younger. Most of these younger COVID-19 decedents presented with pre-existing medical conditions prior to SARS-CoV-2 infection. These included overweight and obesity, arterial hypertension, asthma, and obstructive sleep apnea, as well as graft-versus-host disease following cancer and bone marrow transplantation. Furthermore, clinical histories and autopsy results revealed a disproportionally high prevalence of thromboembolism and ischemic organ damage in this patient cohort. Histopathology and laboratory results indicated coagulopathies, signs of immune dysregulation, and liver damage. CONCLUSIONS: In conclusion, pre-existing health conditions may increase the risk of severe and fatal COVID-19 in younger patients, who may be especially prone to developing thromboembolic complications, immune dysregulation, and liver damage.

Association Between SARS-CoV-2 Infection and Immune-Mediated Myopathy in Patients Who Have Died.

Importance: Myalgia, increased levels of creatine kinase, and persistent muscle weakness have been reported in patients with COVID-19. Objective: To study skeletal muscle and myocardial inflammation in patients with COVID-19 who had died. Design, Setting, and Participants: This case-control autopsy series was conducted in a university hospital as a multidisciplinary postmortem investigation. Patients with COVID-19 or other critical illnesses who had died between March 2020 and February 2021 and on whom an autopsy was performed were included. Individuals for whom informed consent to autopsy was available and the postmortem interval was less than 6 days were randomly selected. Individuals who were infected with SARS-CoV-2 per polymerase chain reaction test results and had clinical features suggestive of COVID-19 were compared with individuals with negative SARS-CoV-2 polymerase chain reaction test results and an absence of clinical features suggestive of COVID-19. Main Outcomes and Measures: Inflammation of skeletal muscle tissue was assessed by quantification of immune cell infiltrates, expression of major histocompatibility complex (MHC) class I and class II antigens on the sarcolemma, and a blinded evaluation on a visual analog scale ranging from absence of pathology to the most pronounced pathology. Inflammation of cardiac muscles was assessed by quantification of immune cell infiltrates. Results: Forty-three patients with COVID-19 (median [interquartile range] age, 72 [16] years; 31 men [72%]) and 11 patients with diseases other than COVID-19 (median [interquartile range] age, 71 [5] years; 7 men [64%]) were included. Skeletal muscle samples from the patients who died with COVID-19 showed a higher overall pathology score (mean [SD], 3.4 [1.8] vs 1.5 [1.0]; 95% CI, 0-3; P < .001) and a higher inflammation score (mean [SD], 3.5 [2.1] vs 1.0 [0.6]; 95% CI, 0-4; P < .001). Relevant expression of MHC class I antigens on the sarcolemma was present in 23 of 42 specimens from patients with COVID-19 (55%) and upregulation of MHC class II antigens in 7 of 42 specimens from patients with COVID-19 (17%), but neither were found in any of the controls. Increased numbers of natural killer cells (median [interquartile range], 8 [8] vs 3 [4] cells per 10 high-power fields; 95% CI, 1-10 cells per 10 high-power fields; P < .001) were found. Skeletal muscles showed more inflammatory features than cardiac muscles, and inflammation was most pronounced in patients with COVID-19 with chronic courses. In some muscle specimens, SARS-CoV-2 RNA was detected by reverse transcription-polymerase chain reaction, but no evidence for a direct viral infection of myofibers was found by immunohistochemistry and electron microscopy. Conclusions and Relevance: In this case-control study of patients who had died with and without COVID-19, most individuals with severe COVID-19 showed signs of myositis ranging from mild to severe. Inflammation of skeletal muscles was associated with the duration of illness and was more pronounced than cardiac inflammation. Detection of viral load was low or negative in most skeletal and cardiac muscles and probably attributable to circulating viral RNA rather than genuine infection of myocytes. This suggests that SARS-CoV-2 may be associated with a postinfectious, immune-mediated myopathy.