The clinical value of CT and SWI in evaluating the occurrence of CMBs in diabetic patients with hypertension / 中国辐射卫生

Objective With the help of computerized tomography (CT) and susceptibility-weighted imaging (SWI) examinations, to analyze and compare the incidence and the prevalent sites of microbleeds (CMBs) in control group, diabetes group, hypertension group and diabetic hypertension group with intracerebral CMBs. The risk factors for the onset of CMBs also will be explored, in order to provide a basis for the selection of clinical diagnosis and treatment options for CMBs. Methods A collection of 174 non-acute patients in the Department of Neurology of Shandong Electric Power Central Hospital from May 2019 to October 2020, including 101 males and 73 females, aged 45-89 years, with an average age of 72 ± 5 years. Divided into four groups according to disease types: Hypertension with type 2 diabetes group, Hypertension group, Type 2 diabetes group, Control group (no hypertension and type 2 diabetes). All patients underwent CT and MRI SWI sequence scans. The 4 groups of patients were matched in terms of gender and age, excluding the influence of gender and age. The incidence, number and distribution of CMBs in the four groups were counted, and the CT and SWI imaging manifestations of CMBs in the four groups were analyzed and compared. Results CT did not find the incidence of CMBs in the brain of patients. SWI imaging showed that CMBs were detected in 58 of 174 patients (incidence rate 33.3%), and CMBs occurred in 24 cases of diabetes and hypertension group (incidence rate 57.1%). CMBs occurred in 21 cases in the hypertension group (incidence rate 46.7%), 8 cases in the diabetes group (incidence rate 22.2%), and CMBs occurred in 5 cases in the control group (incidence rate 9.8%). The incidence of CMBs in the hypertension group and the diabetes combined with hypertension group was significantly higher than that in the control group (P < 0.05). There was no significant difference in the incidence of CMBs in patients with simple diabetes compared with the control group. Also, there was no significant difference in the incidence of CMBs between the diabetes combined with hypertension group and the simple hypertension group. Conclusion CT did not find the incidence of CMBs in the brains of patients in the non-acute phase. SWI could clearly show the CMBs of the enrolled patients. Diabetes is less likely to cause an increase in CMBs. Hypertension is significantly related to the occurrence of CMBs. CMBs associated with hypertension or/and diabetes are common in the basal ganglia and thalamus, which is different from cerebral amyloid angiopathy, which provides a basis for the choice of clinical treatment options.

Large-scale single-cell analysis reveals critical immune characteristics of COVID-19 patients

Dysfunctional immune response in the COVID-19 patients is a recurrent theme impacting symptoms and mortality, yet the detailed understanding of pertinent immune cells is not complete. We applied single-cell RNA sequencing to 284 samples from 205 COVID-19 patients and controls to create a comprehensive immune landscape. Lymphopenia and active T and B cell responses were found to coexist and associated with age, sex and their interactions with COVID-19. Diverse epithelial and immune cell types were observed to be virus-positive and showed dramatic transcriptomic changes. Elevation of ANXA1 and S100A9 in virus-positive squamous epithelial cells may enable the initiation of neutrophil and macrophage responses via the ANXA1-FPR1 and S100A8/9-TLR4 axes. Systemic upregulation of S100A8/A9, mainly by megakaryocytes and monocytes in the peripheral blood, may contribute to the cytokine storms frequently observed in severe patients. Our data provide a rich resource for understanding the pathogenesis and designing effective therapeutic strategies for COVID-19. HIGHLIGHTSO_LILarge-scale scRNA-seq analysis depicts the immune landscape of COVID-19 C_LIO_LILymphopenia and active T and B cell responses coexist and are shaped by age and sex C_LIO_LISARS-CoV-2 infects diverse epithelial and immune cells, inducing distinct responses C_LIO_LICytokine storms with systemic S100A8/A9 are associated with COVID-19 severity C_LI

Single-cell RNA-seq and V(D)J profiling of immune cells in COVID-19 patients

Coronavirus disease 2019 (COVID-19) has caused over 220,000 deaths so far and is still an ongoing global health problem. However, the immunopathological changes of key types of immune cells during and after virus infection remain unclear. Here, we enriched CD3+ and CD19+ lymphocytes from peripheral blood mononuclear cells of COVID-19 patients (severe patients and recovered patients at early or late stages) and healthy people (SARS-CoV-2 negative) and revealed transcriptional profiles and changes in these lymphocytes by comprehensive single-cell transcriptome and V(D)J recombination analyses. We found that although the T lymphocytes were decreased in the blood of patients with virus infection, the remaining T cells still highly expressed inflammatory genes and persisted for a while after recovery in patients. We also observed the potential transition from effector CD8 T cells to central memory T cells in recovered patients at the late stage. Among B lymphocytes, we analyzed the expansion trajectory of a subtype of plasma cells in severe COVID-19 patients and traced the source as atypical memory B cells (AMBCs). Additional BCR and TCR analyses revealed a high level of clonal expansion in patients with severe COVID-19, especially of B lymphocytes, and the clonally expanded B cells highly expressed genes related to inflammatory responses and lymphocyte activation. V-J gene usage and clonal types of higher frequency in COVID-19 patients were also summarized. Taken together, our results provide crucial insights into the immune response against patients with severe COVID-19 and recovered patients and valuable information for the development of vaccines and therapeutic strategies.

Wear Simulation of Tibiofemoral Joint Surface of Total Knee Prosthesis with High Conformity / 医用生物力学

Objective To investigate the effect of the tibiofemoral joint surface with high conformity on total knee prosthesis motion and insert wear. Methods A type of knee prosthesis with a high coronal conformity was designed and manufactured, and its insert wear was studied by in vitro wear testing combined with finite element simulation. ResultsThe mass wear rates calculated by the in vitro wear testing and finite element simulation were (14.29±3.19) mg/MC and 14.67 mg/MC (MC, million cycle), respectively. After five MCs, the areas of the insert wear obtained by both the methods were basically consistent, and severe wear was found to occur in the middle part of the insert. ConclusionsThe result of the finite element simulation coincided with that of the in vitro testing. The wear rate of the tibiofemoral joint surface of the total knee prosthesis with a high coronal conformity was relatively low. The research outcomes have practical significance for the evaluation and clinical application of the total knee prosthesis with a high conformity.