Covid-19 CasesTo rapidly communicate information on the global clinical effort against Covid-19, the Journal has initiated a series of case reports that offer important teaching points or novel findings. The case reports should be viewed as observations rather than as recommendations for evaluation or treatment. In the interest of timeliness, these reports are evaluated by in-house editors, with peer review reserved for key points as needed. Coagulopathy and Antiphospholipid Antibodies in Patients with Covid-19We describe a patient with Covid-19 and clinically significant coagulopathy, antiphospholipid antibodies, and multiple infarcts. He was one of three patients with these findings in an intensive care unit designated for patients with Covid-19. This unit, which was managed by a multidisciplinary team from Peking Union Medical College Hospital in the Sino-French New City Branch of Tongji Hospital in Wuhan, China, was set up on an emergency basis to accept the most critically ill patients during the outbreak of Covid-19. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) infection was confirmed in all the patients by reverse-transcriptase-polymerase-chain-reaction (RT-PCR) assay or serologic testing.A 69-year-old man with a history of hypertension, diabetes, and stroke presented with fever, cough, dyspnea, diarrhea, and headache. Covid-19 was diagnosed in the patient on January 25, 2020, on the basis of RT-PCR testing that detected SARS-CoV-2. The initial treatment was supportive; however, the illness subsequently progressed to hypoxemic respiratory failure warranting the initiation of invasive mechanical ventilation.

Background Coronary artery disease (CAD) is associated with gut microbiota alterations in different populations. Gut microbe-derived metabolites have been proposed as markers of major adverse cardiac events. However, the relationship between the gut microbiome and the different stages of CAD pathophysiology remains to be established by a systematic study. Results Based on multi-omic analyses (sequencing of the V3-V4 regions of the 16S rRNA gene and metabolomics) of 161 CAD patients and 40 healthy controls, we found that the composition of both the gut microbiota and metabolites changed significantly with CAD severity. We identified 29 metabolite modules that were separately classified as being positively or negatively correlated with CAD phenotypes, and the bacterial co-abundance group (CAG) with characteristic changes at different stages of CAD was represented by Roseburia , Klebsiella , Clostridium IV and Ruminococcaceae . The result revealed that certain bacteria might affect atherosclerosis by modulating the metabolic pathways of the host, such as taurine, sphingolipid and ceramide, and benzene metabolism. Moreover, a disease classifier based on differential levels of microbes and metabolites was constructed to discriminate cases from controls and was even able to distinguish stable coronary artery disease from acute coronary syndrome accurately. Conclusion Overall, the composition and functions of the gut microbial community differed from healthy controls to diverse coronary artery disease subtypes. Our study identified the relationships between the features of the gut microbiota and circulating metabolites, providing a new direction for future studies aiming to understand the host–gut microbiota interplay in atherosclerotic pathogenesis. Electronic supplementary material The online version of this article (10.1186/s40168-019-0683-9) contains supplementary material, which is available to authorized users.

Objective Coagulopathy is one of the characteristics observed in critically ill patients with coronavirus disease 2019 (COVID‐19). Antiphospholipid antibodies (aPLs) contribute to coagulopathy, though their role in COVID‐19 remains unclear. This study was undertaken to determine the prevalence and characteristics of aPLs in patients with COVID‐19. Methods Sera collected from 66 COVID‐19 patients who were critically ill and 13 COVID‐19 patients who were not critically ill were tested by chemiluminescence immunoassay for anticardiolipin antibodies (aCLs), anti–β2‐glycoprotein I (anti‐β2GPI) (IgG, IgM, and IgA), and IgG anti‐β2GPI–domain 1 (anti‐β2GPI–D1) and IgM and IgG anti–phosphatidylserine/prothrombin (anti‐PS/PT) antibodies were detected in the serum by enzyme‐linked immunosorbent assay. Results Of the 66 COVID‐19 patients in critical condition, aPLs were detected in 31 (47% ). Antiphospholipid antibodies were not present among COVID‐19 patients who were not in critical condition. The IgA anti‐β2GPI antibody was the most commonly observed aPL in patients with COVID‐19 and was present in 28.8% (19 of 66) of the critically ill patients, followed by IgA aCLs (17 of 66, or 25.8%) and IgG anti‐β2GPI (12 of 66, or 18.2%). For multiple aPLs, IgA anti‐β2GPI + IgA aCLs was the most common antibody profile observed (15 of 66, or 22.7%), followed by IgA anti‐β2GPI + IgA aCL + IgG anti‐β2GPI (10 of 66, or 15.2%). Antiphospholipid antibodies emerge ~35–39 days after disease onset. A dynamic analysis of aPLs revealed 4 patterns based on the persistence or transient appearance of the aPLs. Patients with multiple aPLs had a significantly higher incidence of cerebral infarction compared to patients who were negative for aPLs (P = 0.023). Conclusion Antiphospholipid antibodies were common in critically ill patients with COVID‐19. Repeated testing demonstrating medium to high titers of aPLs and the number of aPL types a patient is positive for may help in identifying patients who are at risk of developing cerebral infarction. Antiphospholipid antibodies may be transient and disappear within a few weeks, but in genetically predisposed patients, COVID‐19 may trigger the development of an autoimmune condition similar to the antiphospholipid syndrome (APS), referred to as “COVID‐19–induced APS‐like syndrome.” Long‐term follow‐up of COVID‐19 patients who are positive for aPLs would be of great importance in understanding the pathogenesis of this novel coronavirus.

The baiji, or Yangtze River dolphin (Lipotes vexillifer), is a flagship species for the conservation of aquatic animals and ecosystems in the Yangtze River of China; however, this species has now been recognized as functionally extinct. Here we report a high-quality draft genome and three re-sequenced genomes of L. vexillifer using Illumina short-read sequencing technology. Comparative genomic analyses reveal that cetaceans have a slow molecular clock and molecular adaptations to their aquatic lifestyle. We also find a significantly lower number of heterozygous single nucleotide polymorphisms in the baiji compared to all other mammalian genomes reported thus far. A reconstruction of the demographic history of the baiji indicates that a bottleneck occurred near the end of the last deglaciation, a time coinciding with a rapid decrease in temperature and the rise of eustatic sea level.

Background: The complications of coronavirus disease 2019 (COVID-19) involved multiple organs or systems, especially in critically ill patients. We aim to investigate the neurological complications in critically ill patients with COVID-19. Methods: This retrospective single-center case series analyzed critically ill patients with COVID-19 at the intensive care unit of Tongji Hospital, Wuhan, China from February 5 to April 2, 2020. Demographic data, clinical and laboratory findings, comorbidities and treatments were collected and analyzed. Results: Among 86 patients with confirmed COVID-19, 54 patients (62.8%) were male, and the mean (SD) age was 66.6 (11.1) years. Overall, 65% patients presented with at least one neurological symptom. Twenty patients (23.3%) had symptoms involving the central nervous system, including delirium, cerebrovascular diseases and hypoxic-ischemic brain injury, while 6 patients (7%) had neuromuscular involvement. Seven of 86 patients exhibited new stroke and 6 (7%) cases were ischemic. A significantly higher prevalence of antiphospholipid antibodies was observed in patients with ischemic stroke than in those without stroke (83.3 vs. 26.9%, p < 0.05). Patients with ischemic stroke were more likely to have a higher myoglobulin level, and a lower hemoglobin level. Conclusions: The clinical spectrum of neurological complications in critically ill patients with COVID-19 was broad. Stroke, delirium and neuromuscular diseases are common neurological complications of COVID-19. Physicians should pay close attention to neurological complications in critically ill patients with COVID-19.

Aims Cardiac complications are common and associated with mortality in critically ill patients with COVID-19; however, the diagnostic and prognostic implications of critical care echocardiography (CCE) have not been studied. Methods and results A cohort of 43 patients with COVID-19 who were in the intensive care unit (ICU) underwent bedside CCE during their disease course. Demographic, clinical, and survival data were collected. The echocardiographic analyses revealed high frequencies of pericardial effusion (90.7%), increased left ventricular mass index (60.5%), elevated relative wall thickness (76.7%), and reduced left ventricular stroke volume index (LVSVi; 53.5%) and cardiac index (51.2%). Twenty-two (51.2%) patients died in the ICU. In multivariate Cox regression, the strongest predictor of in-ICU death was decreased cardiac index [hazard ratio (HR), 0.67, 95% confidence interval (CI), 0.45-0.98; P = 0.041], after adjusting for male sex, shock status, high-sensitivity cardiac troponin I, and N-terminal pro-B-type natriuretic peptide. Negative associations with mortality were observed for LVSVi (HR, 0.91, 95% CI 0.85-0.96; P = 0.002), tricuspid annular plane systolic excursion (HR, 0.74, 95% CI 0.64-0.84; P < 0.001), and S′ (HR, 0.78, 95% CI 0.69-0.88; P < 0.001). Kaplan-Meier analyses indicated that reductions in LVSVi, cardiac index, TAPSE, and S′ were associated with a shorter survival time. Conclusions Pericardial effusion and increased ventricular mass in COVID-19 might indicate a swollen heart. Both left and right heart dysfunction and a reduced cardiac index may lead to an increased risk of mortality. Clinicians should pay special attention to cardiac haemodynamic disorders in critical patients with COVID-19.

There have been arguments on whether angiotensin-converting enzyme inhibitors (ACEI) and angiotensin receptor blockers (ARB) treatment alters the risk of COVID-19 susceptibility and disease severity. We identified a total of 102 eligible studies for systematic review, in which 49 studies adjusting for confounders were included in the meta-analysis. We found no association between prior ACEI/ARB use and risk of SARS-CoV-2 infection in general population (adjusted OR [aOR] 1.00, 95% confidence interval [CI] 0.94-1.05). The risk of mortality (aOR 0.87, 95%CI 0.66-1.04) and severe outcomes (aOR 0.95, 95%CI 0.73-1.24) are also unchanged among COVID-19 patients taking ACEI/ARB. These findings remain consistent in subgroup analyses stratified by populations, drug exposures and in other secondary outcomes. This systematic review provides evidence-based support to current medical guidelines and position statements that ACEI/ARB should not be discontinued. Additionally, there has been no evidence for initiating ACEI/ARB regimen as prevention or treatment of COVID-19.

Hypoxia was a major challenge faced by cetaceans during the course of secondary aquatic adaptation. Although physiological traits of hypoxia tolerance in cetaceans have been well characterized, the underlying molecular mechanisms remain unknown. We investigated the sequences of 17 hypoxia-tolerance-related genes in representative cetaceans to provide a comprehensive insight into the genetic basis of hypoxia tolerance in these animals. Genes involved in carrying and transporting oxygen in the blood and muscle (hemoglobin-α and β, myoglobin), and genes involved in the regulation of vasoconstriction (endothelin-1, -2, and -3; endothelin receptor type A and B; adrenergic receptor α-1D; and arginine vasopressin) appear to have undergone adaptive evolution, evidence for positive selection on their particular sites, and radical physiochemical property changes of selected condons. Interestingly, “long-diving” cetaceans had relatively higher ω (dN/dS) values than “short-diving” cetaceans for the hemoglobin β gene, indicating divergent selective pressure presented in cetacean lineages with different diving abilities. Additionally, parallel positive selection or amino acid changes (ADRA1D: P50A, A53G, AVPR1B: I/V270T) among animals exposed to different hypoxia habitats reflect functional convergence or similar genetic mechanisms of hypoxia tolerance. In summary, positive selection, divergent selective pressures, and parallel evolution at the molecular level provided some new insights into the genetic adaptation of hypoxia tolerance.