Seasonal variation in COVID-19 incidence could impact the trajectory of the pandemic. Using global linelist data on COVID-19 cases reported until 29 th February 2020 and global gridded temperature data, and after adjusting for surveillance capacity and time since first imported case, higher average temperature was strongly associated with lower COVID-19 incidence for temperatures of 1°C and higher. However, temperature explained a relatively modest amount of the total variation in COVID-19 incidence. These preliminary findings support stringent containment efforts in Europe and elsewhere.

A phosphorothioate oligonucleotide that has been employed to inhibit HIV-1 viral expression in chronically infected H9 cells was examined for cellular uptake and subcellular distribution. The relationship between extracellular oligonucleotide concentration and the distribution and accumulation into subcellular organelles is important to the design, potential side effects, and understanding of a therapeutically useful antisense oligonucleotide. These studies employed uptake of both 35S- and fluorescence-labeled phosphorothioate oligonucleotides. Experiments with V79, HeLa, H9, and fresh human peripheral blood monocytes indicate that accumulations of oligonucleotide inside cells exceeds the concentration of oligonucleotide in culture media by over 100 times following 1 h of exposure at 37 degrees C. Uptake is more efficient at low concentrations, suggesting a saturable process. The total oligonucleotide that remains in cells begins to reach a plateau after 45-60 min, indicating either that efflux pathways exist or that uptake is saturable. Subcellular fractionation studies with 35S-labeled phosphorothioate demonstrate the oligonucleotide is sequestered into both the nuclei and the mitochondria of cultured HeLa cells in a time-dependent manner. The subcellular fractionation was examined with fluorescence-labeled phosphorothioate by both confocal and fluorescence microscopy, which confirmed the rate and localization of oligonucleotide into cultured cells. Finally, cellular uptake is not uniform for all cells in a nonsynchronous culture.

The objectives of this study were to assess the dynamics of the SARS-CoV-2 anti-RBD-IgG response over time among older people after COVID-19 infection or vaccination and its comparison with indicative levels of protection. Geriatric patients with SARS-CoV-2 serological test results were included and divided into three groups. A vaccine group ( n = 34), a group of natural COVID-19 infection ( n = 32), and a group who contracted COVID-19 less than 15 days after the first injection ( n = 17). Eighty-three patients were included; the median age with IQR was 87 (81–91) years. In the vaccine group at 1 month since the first vaccination, the median titer of anti-RBD-IgG was 620 (217–1874) BAU/ml with 87% of patients above the theoretical protective threshold of 141 BAU/ml according to Dimeglio et al. (J Infec. 84(2):248–88, [ 7 ]). Seven months after the first vaccination, this titer decreased to 30 (19–58) BAU/ml with 9.5% of patients > 141 BAU/ml. In the natural COVID-19 infection group, at 1 month since the date of first symptom onset, the median titer was 798 (325–1320) BAU/ml with 86.7% of patients > 141 BAU/ml and fell to 88 (37–385) with 42.9% of patients > 141 BAU/ml at 2 months. The natural infection group was vaccinated 3 months after the infection. Five months after the vaccination cycle, the median titer was 2048 (471–4386) BAU/ml with 83.3% of patients > 141 BAU/ml. This supports the clinical results describing the decrease in vaccine protection over time and suggests that vaccination after infection can maintain significantly higher antibody titer levels for a prolonged period of time.

A better description and understanding of Coronavirus Disease 2019 (COVID-19) is needed. Virological assessment has been encouraged by the WHO. 1 The objectives of this study were to assess the prevalence of SARS-CoV-2 RT-PCR positive tests 1 month after the date of first symptom onset (dso) in COVID-19 infected older adults, to assess late stool SARS-CoV-2 RT-PCR results, COVID-19 serological status and associated factors with death 1 month after the dso.

Previous studies have demonstrated that mouse embryonal carcinoma (EC) cells produce at least two growth factors: one related to platelet-derived growth factor (PDGF) and another related to basic fibroblast growth factor (FGFb). Since human EC cell lines are being used with increased frequency, the current study examined whether human EC cells produce growth factors, in particular those produced by mouse EC cells. In this study, it was determined that the human EC cell line NT2/D1 produces a heat-labile heparin-binding growth factor that behaves like FGF in a bioassay. Three additional criteria suggest that this factor is closely related or identical to FGFb. The factor from NT2/D1 EC cells, bovine FGFb and FGFb produced by the human hepatoma cell line SK-HEP-1 elute from heparin at similar salt concentrations. The factor produced by NT2/D1 EC cells exhibits a thermal stability curve that is nearly identical to those for bovine FGFb and FGFb from SK-HEP-1 cells. Lastly, NT2/D1 and SK-HEP-1 cells express transcripts of the same size that hybridize with a cDNA probe for human FGFb. In the course of these studies it was determined that NT2/D1 EC cells also express several transcripts that hybridize with a cDNA probe for the human PDGF A-chain. Thus, our findings suggest that the pattern of growth factor production by human and mouse EC cells is evolutionarily conserved.

Here, we present the case of an 81‐year‐old male patient, who was hospitalized for a severe form of COVID‐19. Transthoracic echocardiogram (TTE) performed 1 month after symptom onset was normal. Respiratory evolution was favourable, and the patient was discharged at Day 78. At 6 months, despite a good functional recovery, he presented pulmonary sequelae, and the TTE revealed a clear reduction of left ventricular ejection fraction (LVEF) and mild LV dilatation without cardiac symptoms. The cardiac magnetic resonance (CMR) using Lake Louise Criteria (LLC), T1 and T2 mapping showed focal infero‐basal LV wall oedema, elevated T1 and T2 myocardial relaxation times especially in basal inferior and infero‐lateral LV walls, and sub‐epicardial late gadolinium enhancement in those LV walls. The diagnosis of active myocarditis was raised especially based on TTE abnormalities and CMR LLC, T1 and T2 mapping. Currently, we are not aware of published reports of a 6 month post‐COVID‐19 active myocarditis.

Kremer S. SARS-CoV-2 viral dynamics in immunocompromised patients.

BackgroundInflammatory myopathies (IM) are life-threatening but treatable diseases. The risk factors for admission in Intensive care unit (ICU), the management and the outcome of patients with IM admitted to ICU has not yet been assessed.ObjectivesTo assess the clinical features, risk factors and outcome of patients with IM admitted in ICU.MethodsA single centre cohort of 509 patients with IM was screened for admission in ICU from 1992 to 2017. Patients admitted for trauma or for complications from elective surgery were excluded. Control patients with IM who had not been hospitalised in ICU were randomly selected from the cohort.ResultsThirty-two ICU admissions were recorded in 27 IM patients during the study period (<0.05% of admissions over this 25 year period). Three IM patients were admitted more than once.Characteristics and prognosis of patients in ICUPatients hospitalised in ICU had a mean age of 63 y.±15 with SAPS II score of 58±24 and LODS score of 9±5 corresponding to an intermediate severity at admission in ICU. The delay between IM diagnosis and first ICU admission was 27±43 months. It is noteworthy that 12 patients (44%) were admitted in the ICU within the first month of IM diagnosis, among whom 4 (15%) were diagnosed with IM during ICU stay. Sixteen patients (60%) were not treated at the time of their first ICU admission. In 56% of the ICU stays, patients had active disease at admission. Patients were most frequently admitted for respiratory failure (88%) but cardiac (47%), renal (47%), neurologic (47%), haematological (22%) and hepatic (15%) failures were also recorded. Infections were present in 72% of the ICU stays, with septic shock in 44%. Nine patients (33%) died in ICU and 3 others (11%) within 90 days of the last ICU discharge (vs. 15% during a 7.5±5 years period of follow-up in the control group, p<0.0001).Risk factors of ICU admissionThe case control analysis identified 6 risk factors significantly associated with hospitalisation in the ICU, 3 of which were independently associated with hospitalisation in multivariate analysis. ICU patients had a higher age at first clinical signs of illness (62±13 years old vs. 53±13 years old, p<0.05), they had a higher rate of chronic kidney failure (26% vs. 0%, p<0.05) and higher incidence of arterial or venous thrombosis history (37% vs. 0%, p<0.05). Other risk factors that were only identified in univariate analysis included lower BMI (22.6±4.5 vs. 25.4±6.3), a history of interstitial lung disease (48% vs. 30%) and a higher Charlson comorbidity index (4.6±2.6 vs. 3.3±2).The type of myositis was not significantly associated with admission in ICU, although no patient admitted in ICU had sIBM. It is noteworthy that cumulative number of immunomodulatory treatments in patients at the time of hospitalisation in ICU was lower than in the control group (0.5±0.7 vs. 1.9±0.8 p<0.001).ConclusionsIM patients admitted in ICU frequently have recent onset and untreated active IM with respiratory failure. Admission to ICU is associated with older age and a higher num...