Clinical characteristics and outcomes of immunosuppressed patients hospitalized with COVID-19: experience from London.

BACKGROUND: Coronavirus disease 2019 (COVID-19) is a global health emergency. Despite the widely hypothesized role of a cytokine storm in disease severity, no study thus far has explored the association between immunosuppression and disease severity in patients hospitalized with COVID-19. OBJECTIVE: This study aimed to examine the association between the use of immunosuppressant medication and outcomes of patients hospitalized with COVID-19. METHODS: Nine hundred and eighty-one consecutive patients hospitalized between 12 March 2020 and 15 April 2020, who tested positive for severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2), were enrolled in this cohort study and subdivided by immunosuppression status. The patients were followed up for a minimum of 28 days (median 37 days) for the primary end-point of mortality. Secondary end-points included the composite of intubation or death, and the composite of mortality, intubation or continuous positive airway pressure (CPAP) requirement. RESULTS: During the follow-up period, 354 (36.1%) of study patients died. The immunosuppressed cohort (n = 31) had significantly higher mortality rates (aHR: 2.067, 95% CI: 1.20-3.57, P = 0.009). There was no association between immunosuppression and the composite end-point of mortality or intubation (aHR: 1.49 95% CI: 0.88-2.51, P = 0.14) and of the composite end-point of mortality, intubation or CPAP (aHR: 1.36 95% CI: 0.81-2.30 P = 0.245). CONCLUSION: In this cohort study of 981 confirmed COVID-19 patients consecutively hospitalized at a large North West London hospital, immunosuppressant use was associated with significantly higher mortality rates. These results support the current UK government's early isolation ('shielding') policy for these individuals and should be used to guide future research.

Risk factors for severe disease in patients admitted with COVID-19 to a hospital in London, England: a retrospective cohort study.

COVID-19 has caused a major global pandemic and necessitated unprecedented public health restrictions in almost every country. Understanding risk factors for severe disease in hospitalised patients is critical as the pandemic progresses. This observational cohort study aimed to characterise the independent associations between the clinical outcomes of hospitalised patients and their demographics, comorbidities, blood tests and bedside observations. All patients admitted to Northwick Park Hospital, London, UK between 12 March and 15 April 2020 with COVID-19 were retrospectively identified. The primary outcome was death. Associations were explored using Cox proportional hazards modelling. The study included 981 patients. The mortality rate was 36.0%. Age (adjusted hazard ratio (aHR) 1.53), respiratory disease (aHR 1.37), immunosuppression (aHR 2.23), respiratory rate (aHR 1.28), hypoxia (aHR 1.36), Glasgow Coma Scale <15 (aHR 1.92), urea (aHR 2.67), alkaline phosphatase (aHR 2.53), C-reactive protein (aHR 1.15), lactate (aHR 2.67), platelet count (aHR 0.77) and infiltrates on chest radiograph (aHR 1.89) were all associated with mortality. These important data will aid clinical risk stratification and provide direction for further research.

Bio-inspired CO2 conversion by iron sulfide catalysts under sustainable conditions.

The mineral greigite presents similar surface structures to the active sites found in many modern-day enzymes. We show that particles of greigite can reduce CO2 under ambient conditions into chemicals such as methanol, formic, acetic and pyruvic acid. Our results also lend support to the Origin of Life theory on alkaline hydrothermal vents.

Relationship of CD146 expression to secretion of interleukin (IL)-17, IL-22 and interferon-γ by CD4(+) T cells in patients with inflammatory arthritis.

Expression of the adhesion molecule, CD146/MCAM/MelCAM, on T cells has been associated with recent activation, memory subsets and T helper type 17 (Th17) effector function, and is elevated in inflammatory arthritis. Th17 cells have been implicated in the pathogenesis of rheumatoid arthritis (RA) and spondyloarthritides (SpA). Here, we compared the expression of CD146 on CD4(+) T cells between healthy donors (HD) and patients with RA and SpA [ankylosing spondylitis (AS) or psoriatic arthritis (PsA)] and examined correlations with surface markers and cytokine secretion. Peripheral blood mononuclear cells (PBMC) were obtained from patients and controls, and synovial fluid mononuclear cells (SFMC) from patients. Cytokine production [elicited by phorbol myristate acetate (PMA)/ionomycin] and surface phenotypes were evaluated by flow cytometry. CD146(+) CD4(+) and interleukin (IL)-17(+) CD4(+) T cell frequencies were increased in PBMC of PsA patients, compared with HD, and in SFMC compared with PBMC. CD146(+) CD4(+) T cells were enriched for secretion of IL-17 [alone or with IL-22 or interferon (IFN)-γ] and for some putative Th17-associated surface markers (CD161 and CCR6), but not others (CD26 and IL-23 receptor). CD4(+) T cells producing IL-22 or IFN-γ without IL-17 were also present in the CD146(+) subset, although their enrichment was less marked. Moreover, a majority of cells secreting these cytokines lacked CD146. Thus, CD146 is not a sensitive or specific marker of Th17 cells, but rather correlates with heterogeneous cytokine secretion by subsets of CD4(+) helper T cells.

Validation and utilisation of high-coverage next-generation sequencing to deliver the pharmacological audit trail.

BACKGROUND: Predictive biomarker development is a key challenge for novel cancer therapeutics. We explored the feasibility of next-generation sequencing (NGS) to validate exploratory genomic biomarkers that impact phase I trial selection. METHODS: We prospectively enrolled 158 patients with advanced solid tumours referred for phase I clinical trials at the Royal Marsden Hospital (October 2012 to March 2013). After fresh and/or archived tumour tissue were obtained, 93 patients remained candidates for phase I trials. Results from tumour sequencing on the Illumina MiSeq were cross-validated in 27 out of 93 patients on the Ion Torrent Personal Genome Machine (IT-PGM) blinded to results. MiSeq validation with Sequenom MassARRAY OncoCarta 1.0 (Sequenom Inc., San Diego, CA, USA) was performed in a separate cohort. RESULTS: We found 97% concordance of mutation calls by MiSeq and IT-PGM at a variant allele frequency ⩾13% and ⩾500 × depth coverage, and 91% concordance between MiSeq and Sequenom. Common 'actionable' mutations involved deoxyribonucleic acid (DNA) repair (51%), RAS-RAF-MEK (35%), Wnt (26%), and PI3K-AKT-mTOR (24%) signalling. Out of 53, 29 (55%) patients participating in phase I trials were recommended based on identified actionable mutations. CONCLUSIONS: Targeted high-coverage NGS panels are a highly feasible single-centre technology well-suited to cross-platform validation, enrichment of trials with molecularly defined populations and hypothesis testing early in drug development.

Peri-operative care of the elderly 2014: Association of Anaesthetists of Great Britain and Ireland.

Increasing numbers of elderly patients are undergoing an increasing variety of surgical procedures. There is an age-related decline in physiological reserve, which may be compounded by illness, cognitive decline, frailty and polypharmacy. Compared with younger surgical patients, the elderly are at relatively higher risk of mortality and morbidity after elective and (especially) emergency surgery. Multidisciplinary care improves outcomes for elderly surgical patients. Protocol-driven integrated pathways guide care effectively, but must be individualised to suit each patient. The AAGBI strongly supports an expanded role for senior geriatricians in coordinating peri-operative care for the elderly, with input from senior anaesthetists (consultants/associate specialists) and surgeons. The aims of peri-operative care are to treat elderly patients in a timely, dignified manner, and to optimise rehabilitation by avoiding postoperative complications. Effective peri-operative care improves the likelihood of very elderly surgical patients returning to their same pre-morbid place of residence, and maintains the continuity of their community care when in hospital. Postoperative delirium is common, but underdiagnosed, in elderly surgical patients, and delays rehabilitation. Multimodal intervention strategies are recommended for preventing postoperative delirium. Peri-operative pain is common, but underappreciated, in elderly surgical patients, particularly if they are cognitively impaired. Anaesthetists should administer opioid-sparing analgesia where possible, and follow published guidance on the management of pain in older people. Elderly patients should be assumed to have the mental capacity to make decisions about their treatment. Good communication is essential to this process. If they clearly lack that capacity, proxy information should be sought to determine what treatment, if any, is in the patient's best interests. Anaesthetists must not ration surgical or critical care on the basis of age, but must be involved in discussions about the utility of surgery and/or resuscitation. The evidence base informing peri-operative care for the elderly remains poor. Anaesthetists are strongly encouraged to become involved in national audit projects and outcomes research specifically involving elderly surgical patients.

Simultaneous bilateral total knee replacement: a persistent controversy.

The benefits and risks of Simultaneous Bilateral Total Knee Replacement (SBTKR) remain controversial. A review of the English speaking literature was undertaken and found that many papers took staunch positions either for or against the procedure. It was also noted that earlier papers supporting SBTKR suggested cost benefits. There was a huge disparity in the incidence of mortality and morbidity and it was not possible to compare many papers, because in some medically frail patients were excluded from the SBTKR cohorts. In large published series the proportion of patients having a SBTKR varied between 3% and 70%. Many, but not all, series highlighted age and co-morbidity as risk factors. Overall there was no clear case for or against SBTKR. The evidence suggested that careful preoperative assessment and patient selection on a strict protocol were essential. The procedure should be confined to hospitals where high dependency nursing is readily available and the literature indicated that the risk is less in high through-put units. By refining preoperative assessment and preparation it can be a safe and effective procedure in an appropriate clinical setting for postoperative care.

Causes of death in the Kasekela chimpanzees of Gombe National Park, Tanzania.

Understanding the rates and causes of mortality in wild chimpanzee populations has important implications for a variety of fields, including wildlife conservation and human evolution. Because chimpanzees are long-lived, accurate mortality data requires very long-term studies. Here, we analyze 47 years of data on the Kasekela community in Gombe National Park. Community size fluctuated between 38 and 60, containing 60 individuals in 2006. From records on 220 chimpanzees and 130 deaths, we found that the most important cause of mortality in the Kasekela community was illness (58% of deaths with known cause), followed by intraspecific aggression (20% of deaths with known cause). Previous studies at other sites also found that illness was the primary cause of mortality and that some epidemic disease could be traced to humans. As at other study sites, most deaths due to illness occurred during epidemics, and the most common category of disease was respiratory. Intraspecific lethal aggression occurred within the community, including the killing of infants by both males and females, and among adult males during the course of dominance-related aggression. Aggression between communities resulted in the deaths of at least five adult males and two adult females in the Kasekela and Kahama communities. The frequency of intercommunity violence appears to vary considerably among sites and over time. Intercommunity lethal aggression involving the Kasekela community was observed most frequently during two periods. Other less common causes of death included injury, loss of mother, maternal disability, and poaching.

IGF2 gene characterization and association with rib eye area in beef cattle.

Insulin-like growth factor 2 (IGF2) is an imprinted gene expressed in most tissues affecting lean muscle content in mice, pigs and cattle. We previously identified the bovine IGF2 c.-292C>T SNP in the non-translated exon 2. Using this SNP, we demonstrated biallelic expression of IGF2 after birth. Seven alternatively spliced mRNA transcripts of IGF2 were expressed among 15 tissues. An IGF2 pseudogene (psiIGF2) was identified with sequence identical to at least IGF2 exons 2 and 3 without the intervening intron. The biallelic expression of this c.-292C>T SNP was associated with an increase in rib eye area (REA) in two populations of cattle, with the C.-292C allele associated with a 10% increase. A significant association with per cent fat was found in one of the populations.

Does HLA-B27 influence the monocyte inflammatory response to lipopolysaccharide?

OBJECTIVES: How human leucocyte antigen B27 (HLA-B27) contributes towards arthritis susceptibility is still unclear, but effects on the response to bacteria unrelated to the classical antigen presenting role of B27 have been suggested. This study investigated whether HLA-B27 modulates the innate response to lipopolysaccharide (LPS), a component shared between all Gram negative bacteria that can trigger reactive arthritis. METHODS: Pools of U937 transfectants expressing either HLA-B27, HLA-A2 or the expression plasmid alone were differentiated with phorbol 12-myristate 13-acetate and stimulated with LPS. Supernatants were analysed for tumour necrosis factor-alpha (TNF-alpha) secretion and the gene expression profiles of unstimulated and LPS-stimulated cells were determined by microarray analysis. Changes in gene expression that are indicative of an unfolded protein response (UPR) were also analysed by quantitative polymerase chain reaction (PCR). RESULTS: TNF-alpha secretion, a biological marker of the inflammatory response to LPS, was not significantly different between U937-B27 and U937-control. No differences in gene expression between unstimulated U937-B27 and U937-control lines were detected. Both U937-control and U937-B27 exhibited a stereotypic response to LPS. Only one gene, OAS2, was differentially expressed by these cell lines, and this was confirmed by quantitative PCR. Analysis of XBP-1 splicing suggested that the UPR is induced following the LPS stimulation, but this increase was seen in all transfectants. CONCLUSIONS: The expression of B27 does not profoundly alter the gene expression following LPS stimulation. Therefore, additional signals, such as those provided by cytokines or intracellular infection, may be required to reveal any influence of B27 expression on the inflammatory response.

Using retrospective health data from the Gombe chimpanzee study to inform future monitoring efforts.

Disease outbreaks, either in isolation or in concert with other risk factors, can pose serious threats to the long-term persistence of mammal populations, and these risks become elevated as population size decreases and/or population isolation increases. Many chimpanzee study sites are increasingly isolated by loss of habitat due to human encroachment, and managers of parks that contain chimpanzees perceive that disease outbreaks have been and continue to be significant causes of mortality for chimpanzees. Major epidemics at Gombe National Park include suspected polio in 1966; respiratory diseases in 1968, 1987, 1996, 2000, and 2002; and sarcoptic mange in 1997. These outbreaks have led park managers and researchers working in Gombe to conclude that disease poses a substantial risk to the long-term survival of Gombe's chimpanzee population. We surveyed behavioral data records spanning 44 years for health-related data and found a combination of standardized and nonstandardized data for the entire period. Here we present the types of data found during the survey, discuss the usefulness of these data in the context of risk assessment, and describe how our current monitoring effort at Gombe was designed based on our findings.

Development of an interactive learning tool for teaching rheumatology--a simulated clinical case studies program.

OBJECTIVES: To promote independent self-study involving problem solving and decision analysis in the undergraduate medical curriculum, we have developed a series of interactive web-based clinical case studies. METHODS: An initial needs assessment was performed to determine students' attitudes to e-learning. From these results we designed a series of 30 interactive case studies for delivery from a web-server. RESULTS: A survey of 59 undergraduate students believed that online teaching resources were a useful supplement to existing teaching and they could see a positive use for e-learning. The interactive case studies program was well received by a broad range of respondents (n = 84) of different abilities and backgrounds who felt that the program was realistic and clearly presented in an intuitive manner. CONCLUSIONS: The recent increases in numbers of medical undergraduates, the trend towards student-centred learning and the emphasis on patient-related teaching means a great pressure on teachers and resources in medical schools. The case studies program we have developed was effective and well received by both biomedical and medical students. This approach may provide a way to increase the exposure of students to clinical cases involving interactive diagnostic and treatment procedures, that mimic real-world scenarios, but with fewer resource implications.

Alpha beta but not gamma delta T cell clones in synovial fluids of patients with reactive arthritis show active transcription of tumour necrosis factor alpha and interferon gamma.

OBJECTIVE: To compare the cytokine expression profile of three CD8+, three CD4+, and three gammadelta+ T cell clones all derived from the synovial fluids of three patients with reactive arthritis (ReA). METHODS: Complementary DNA based microarrays containing the specific sequence of 56 cytokine transcripts were used for screening. Selected genes were confirmed by reverse transcriptase-polymerase chain reaction assay. RESULTS: Microarray showed that transcripts encoding for interferon gamma and tumour necrosis factor alpha were expressed by all CD8+ and CD4+ T cell clones. However, gammadelta+ T cells predominantly expressed transforming growth factor beta2 and granulocyte monocyte-colony stimulating factor. CONCLUSION: T lymphocyte clones from the joint of patients with ReA exhibit differential cytokine expression profiles. CD8+ and CD4+ T cells demonstrate a Th1 mediated profile, whereas gammadelta+ T cells show a more heterogeneous and less proinflammatory Th3 driven pattern.

Effects of Chlamydia trachomatis infection on the expression of natural killer (NK) cell ligands and susceptibility to NK cell lysis.

Natural killer (NK) cells are an important component of the immediate immune response to infections, including infection by intracellular bacteria. We have investigated recognition of Chlamydia trachomatis (CT) by NK cells and show that these cells are activated to produce interferon (IFN)-gamma when peripheral blood mononuclear cells (PBMC) are stimulated with CT organisms. Furthermore, infection of epithelial cell lines with CT renders them susceptible to lysis by human NK cells. Susceptibility was observed 18-24 h following infection and required protein synthesis by the infecting chlamydiae, but not by the host cell; heat or UV inactivated chlamydiae did not induce susceptibility to NK cell lysis. CT infection was also shown to decrease the expression of classical and non-classical major histocompatibility complex (MHC) molecules on infected cells, thus allowing recognition by NK cells when combined with an activating signal. A candidate activating signal is MICA/B, which was shown to be expressed constitutively on epithelial cells.

The melanocyte inducing factor MITF is stably expressed in cell lines from human clear cell sarcoma.

Clear cell sarcoma (CCS) is associated with the EWS/ATF1 oncogene that is created by chromosomal fusion of the Ewings Sarcoma oncogene (EWS) and the cellular transcription factor ATF1. The melanocytic character of CCS suggests that the microphthalmia-associated transcription factor (Mitf), a major inducer of melanocytic differentiation, may be miss-expressed in CCS. Accordingly, we show that the mRNA and protein of the melanocyte-specific isoform of Mitf (Mitf-M) are present in several cultured CCS cell lines (Su-ccs-1, DTC1, Kao, MST-1, MST-2 and MST-3). The above cell lines thus provide a valuable experimental resource for examining the role of Mitf-M in both CCS and melanocyte differentiation. Melanocyte-specific expression of Mitf-M is achieved via an ATF-dependent melanocyte-specific cAMP-response element in the Mitf-M promoter, and expression of Mitf-M in CCS cells suggests that EWS/ATF1 (a potent and promiscuous activator of cAMP-inducible promoters) may activate the Mitf-M promoter. Surprisingly, however, the Mitf-M promoter is not activated by EWS/ATF1 in transient assays employing CCS cells, melanocytes or nonmelanocytic cells. Thus, our results indicate that Mitf-M promoter activation may require an appropriate chromosomal context in CCS cells or alternatively that the Mitf-M promoter is not directly activated by EWS/ATF1.

Characterization of the humoral immune response to Chlamydia outer membrane protein 2 in chlamydial infection.

Detection of antibodies to an outer membrane protein 2 (OMP2) by enzyme-linked immunosorbent assay (ELISA) by using either the Chlamydia trachomatis- or the Chlamydia pneumoniae-specific protein was investigated. OMP2 is an immunodominant antigen giving rise to antibody responses in humans infected with different C. trachomatis serovars (A to C and D to K) or with C. pneumoniae, which could be detected by OMP2 ELISA. OMP2 ELISA is not species specific, but antibody titers were usually higher on the homologous protein. The sensitivity of this assay was high but varied according to the "gold standard" applied. Levels of antibody to C. pneumoniae OMP2 as detected by ELISA seem to return to background or near-background values within a shorter period of time compared to antibodies to C. pneumoniae detected by microimmunofluorescence (MIF), making it more likely that positive results in ELISA reflect recent infection. Thus, OMP2 ELISA has distinct advantages over MIF and commercially available ELISAs and might be a useful tool for the serodiagnosis of chlamydial infection.

Recognition of the 60 kilodalton cysteine-rich outer membrane protein OMP2 by CD4(+) T cells from humans infected with Chlamydia trachomatis.

T cell-mediated immunity is important in the control of chlamydia infection but chlamydia-specific T cells are also implicated in the inflammation and tissue damage which characterize chlamydia associated diseases. To investigate target antigens of the T cell-mediated immune response to chlamydia infection, Chlamydia trachomatis-specific CD4+ T cell clones were isolated from a patient with chlamydia-induced reactive arthritis. T cell immunoblotting indicated that an antigen of approximately 60 kilodaltons molecular mass was recognized, and recombinant 60 kilodalton cysteine-rich outer membrane 2 (OMP2) proved to be stimulatory. By using deletion constructs and synthetic peptides an epitope presented by HLA-DRB1*0401 was defined and proved to contain the nonamer peptide within the OMP2 sequence predicted to have the greatest binding affinity for DRB1*0401 The sequence of the epitope is conserved in all C. trachomatis strains but not in C. pneumoniae. Investigation of patients with acute urethritis and additional patients with sexually acquired reactive arthritis showed that OMP2-reactive T cells were readily detectable in peripheral blood and synovial fluid. Thus OMP2 is a target antigen of the T cell-mediated immune response to CT infection.