A detection method for relative response of a detector matrix / 中华放射医学与防护杂志

Objective:To test the relative response of a detector matrix used for measuring of the dose distribution in radiotherapy in order to ensure the accuracy and reliability of dose distribution measurement result.Methods:The two adjacent detectors can be irradiated at the same radiation dose by translating the detector matrix. The relative response of each detector to the reference detector can be obtained by combining the recursive algorithm. At the same time, the measurement data at different test steps are corrected to the reference step by setting the reference step, which correct the influence on the relative response result caused by the variation of the radiation condition and the detector response.Results:Based on the actual test of a 32 × 32 detector matrix, the relative response of each detector of the detected detector matrix to the reference detector varied from 0.896 to 1.077, with the expanded uncertainty of the relative response result being 0.8% ( k=2). Conclusions:On the premise of no known distribution of a radiation field, the relative response relationship of each detector of a detector matrix can be obtained by this method accurately and expediently, which provides a basic method for the performance evaluation of the detector matrix. The same idea can also be used to determine the relative response relationship of other detector matrices for different measurement purposes.

Inactivation of SARS Coronavirus 2 and COVID-19 patient samples for contemporary immunology and metabolomics studies

In late 2019, severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) emerged from Wuhan, China spurring the Coronavirus Disease-19 (COVID-19) pandemic that has resulted in over 219 million confirmed cases and nearly 4.6 million deaths worldwide. Intensive research efforts ensued to constrain SARS-CoV-2 and reduce COVID-19 disease burden. Due to the severity of this disease, the US Centers for Disease Control and Prevention (CDC) and World Health Organization (WHO) recommend that manipulation of active viral cultures of SARS-CoV-2 and respiratory secretions from COVID-19 patients be performed in biosafety level 3 (BSL3) containment laboratories. Therefore, it is imperative to develop viral inactivation procedures that permit samples to be transferred and manipulated at lower containment levels (i.e., BSL2), and maintain the fidelity of downstream assays to expedite the development of medical countermeasures (MCMs). We demonstrate optimal conditions for complete viral inactivation following fixation of infected cells with paraformaldehyde solution or other commonly-used branded reagents for flow cytometry, UVC inactivation in sera and respiratory secretions for protein and antibody detection assays, heat inactivation following cDNA amplification of single-cell emulsions for droplet-based single-cell mRNA sequencing applications, and extraction with an organic solvent for metabolomic studies. Thus, we provide a suite of protocols for viral inactivation of SARS-CoV-2 and COVID-19 patient samples for downstream contemporary immunology assays that facilitate sample transfer to BSL2, providing a conceptual framework for rapid initiation of high-fidelity research as the COVID-19 pandemic continues.

Pathogenic neutrophilia drives acute respiratory distress syndrome in severe COVID-19 patients

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) and the ensuing COVID-19 pandemic have caused [~]40 million cases and over 648,000 deaths in the United States alone. Troubling disparities in COVID-19-associated mortality emerged early, with nearly 70% of deaths confined to Black/African-American (AA) patients in some areas, yet targeted studies within this demographic are scant. Multi-omics single-cell analyses of immune profiles from airways and matching blood samples of Black/AA patients revealed low viral load, yet pronounced and persistent pulmonary neutrophilia with advanced features of cytokine release syndrome and acute respiratory distress syndrome (ARDS), including exacerbated production of IL-8, IL-1{beta}, IL-6, and CCL3/4 along with elevated levels of neutrophil elastase and myeloperoxidase. Circulating S100A12+/IFITM2+ mature neutrophils are recruited via the IL-8/CXCR2 axis, which emerges as a potential therapeutic target to reduce pathogenic neutrophilia and constrain ARDS in severe COVID-19. Graphical AbstractThe lung pathology due to severe COVID-19 is marked by a perpetual pathogenic neutrophilia, leading to acute respiratory distress syndrome (ARDS) even in the absence of viral burden. Circulating mature neutrophils are recruited to the airways via IL-8 (CXCL8)/CXCR2 chemotaxis. Recently migrated neutrophils further differentiate into a transcriptionally active and hyperinflammatory state, with an exacerbated expression of IL-8 (CXCL8), IL-1{beta} (IL1B), CCL3, CCL4, neutrophil elastase (NE), and myeloperoxidase (MPO) activity. Airway neutrophils and recruited inflammatory monocytes further increase their production of IL-8 (CXCL8), perpetuating lung neutrophilia in a feedforward loop. MdCs and T cells produce IL-1{beta} and TNF, driving neutrophils reprogramming and survival. O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=142 SRC="FIGDIR/small/446468v2_ufig1.gif" ALT="Figure 1"> View larger version (43K): org.highwire.dtl.DTLVardef@81fd3aorg.highwire.dtl.DTLVardef@181e63org.highwire.dtl.DTLVardef@172fedcorg.highwire.dtl.DTLVardef@ba55a7_HPS_FORMAT_FIGEXP M_FIG C_FIG

Distinctive features of SARS-CoV-2-specific T cells predict recovery from severe COVID-19

Although T cells are likely players in SARS-CoV-2 immunity, little is known about the phenotypic features of SARS-CoV-2-specific T cells associated with recovery from severe COVID-19. We analyzed T cells from longitudinal specimens of 34 COVID-19 patients with severities ranging from mild (outpatient) to critical culminating in death. Relative to patients that succumbed, individuals that recovered from severe COVID-19 harbored elevated and increasing numbers of SARS-CoV-2-specific T cells capable of homeostatic proliferation. In contrast, fatal COVID-19 displayed elevated numbers of SARS-CoV-2-specific regulatory T cells and a time-dependent escalation in activated bystander CXCR4+ T cells. Together with the demonstration of increased proportions of inflammatory CXCR4+ T cells in the lungs of severe COVID-19 patients, these results support a model whereby lung-homing T cells activated through bystander effects contribute to immunopathology, while a robust, non-suppressive SARS-CoV-2-specific T cell response limits pathogenesis and promotes recovery from severe COVID-19. Graphical Abstract O_FIG O_LINKSMALLFIG WIDTH=200 HEIGHT=197 SRC="FIGDIR/small/21250054v2_ufig1.gif" ALT="Figure 1"> View larger version (73K): org.highwire.dtl.DTLVardef@c82ec8org.highwire.dtl.DTLVardef@778d7forg.highwire.dtl.DTLVardef@ea9130org.highwire.dtl.DTLVardef@1e21805_HPS_FORMAT_FIGEXP M_FIG C_FIG HIGHLIGHTSO_LIDysfunctional spike-specific T cells are characteristic of severe COVID-19 C_LIO_LISpike-specific CD127+ Th1 cells are increased in survivors of severe COVID-19 C_LIO_LISpike-specific Tregs and IL6+ CD8+ T cells are increased in fatal COVID-19 C_LIO_LIEscalation of activated lung-homing CXCR4+ T cells associates with fatal COVID-19 C_LI BRIEF SUMMARYBy conducting CyTOF on total and SARS-CoV-2-specific T cells from longitudinal specimens spanning the entire spectrum of COVID-19 diseases, Neidleman et al. demonstrate that spike-specific Th1 cells capable of IL7-dependent homeostatic proliferation predict survival from severe COVID-19, while Tregs and IL6+ CD8+ T cells recognizing spike predict fatal outcome. Fatal COVID-19 is characterized by escalating activation of bystander CXCR4+ T cells in the lungs. Boosting SARS-CoV-2-specific CD4+ T effector responses while diminishing CXCR4-mediated homing may help recovery from severe disease.

Analysis of clinical characteristics and prognosis of minor solid pseudopapillary tumor of the pancreas / 肿瘤研究与临床

ObjectiveTo investigate the characteristics,treatment and prognosis of solid pseudopapillary tumor of the pancreas(SPTP)in the minor. MethodsCombining minor SPTP cases in literatures and 4 cases, analyzed the clinical and pathological features, and the relationship with sex hormone receptors, the growth and development,treatment and prognosis.ResultsThe clinical manifestations of SPTP in minor were same as adults, but the minors showed significant growth retardation which can be reversed after the tumor surgical removal, like 4 patients all showed secondary sex characteristics of retardation in the group. The protocol of surgical treatment was to ensure complete removal of the tumor and keep the healthy organs as much as possible which reduced the impact to the postoperative growth and development.The premise of operation therapy in the 4 cases was minimization of operation trauma. Minor SPTP prognosis had not been determined. ConclusionThe diagnosis and treatment of minor SPTP should be fully taken into account the characteristics of the minor to ensure that patients can continue long-term growth and development and the quality of life.

CT Diagnosis of Biliary Duct Carcinoma / 实用放射学杂志

Objective To assecess the role of CT in the diagnosis and the reasons of misdiagnosis of biliary duct carcinoma.Methods 23 cases with biliary duct carcinoma pathologically comfirmed were reviewed.Results 2 cases were peripheral type,10 cases were major intrahepatic biliary duct type,7 cases were extrahepatic type and 4 cases ampullar type.The masses within biliary duct were showed by CT in 16 cases.The obstruction of biliary duct was cut off abruptly in 18 cases and narrowing sharply in 5 cases.The intrahepatic biliary duct indicated mild or marked expansion,of them,17 cases were showed as vine and 6 as segmental.The extrahepatic biliary duct were dilated in 11 and gallbladder dilatation in 7.4 cases were misdiagnosed and leaked diagnosis was in one cases by CT preoperation.Conclusion CT is valuable in diagnosis of biliary duct carcinoma,but it still has some limitations.