Severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2) poses a public health threat for which preventive and therapeutic agents are urgently needed. Neutralizing antibodies are a key class of ...therapeutics that may bridge widespread vaccination campaigns and offer a treatment solution in populations less responsive to vaccination. Here, we report that high-throughput microfluidic screening of antigen-specific B cells led to the identification of LY-CoV555 (also known as bamlanivimab), a potent anti-spike neutralizing antibody from a hospitalized, convalescent patient with coronavirus disease 2019 (COVID-19). Biochemical, structural, and functional characterization of LY-CoV555 revealed high-affinity binding to the receptor-binding domain, angiotensin-converting enzyme 2 binding inhibition, and potent neutralizing activity. A pharmacokinetic study of LY-CoV555 conducted in cynomolgus monkeys demonstrated a mean half-life of 13 days and a clearance of 0.22 ml hour
kg
, consistent with a typical human therapeutic antibody. In a rhesus macaque challenge model, prophylactic doses as low as 2.5 mg/kg reduced viral replication in the upper and lower respiratory tract in samples collected through study day 6 after viral inoculation. This antibody has entered clinical testing and is being evaluated across a spectrum of COVID-19 indications, including prevention and treatment.
This study evaluates the prognostic performance of a 15 gene expression profiling (GEP) assay that assigns primary posterior uveal melanomas to prognostic subgroups: class 1 (low metastatic risk) and ...class 2 (high metastatic risk).
Prospective, multicenter study.
A total of 459 patients with posterior uveal melanoma were enrolled from 12 independent centers.
Tumors were classified by GEP as class 1 or class 2. The first 260 samples were also analyzed for chromosome 3 status using a single nucleotide polymorphism assay. Net reclassification improvement analysis was performed to compare the prognostic accuracy of GEP with the 7th edition clinical Tumor-Node-Metastasis (TNM) classification and chromosome 3 status.
Patients were managed for their primary tumor and monitored for metastasis.
The GEP assay successfully classified 446 of 459 cases (97.2%). The GEP was class 1 in 276 cases (61.9%) and class 2 in 170 cases (38.1%). Median follow-up was 17.4 months (mean, 18.0 months). Metastasis was detected in 3 class 1 cases (1.1%) and 44 class 2 cases (25.9%) (log-rank test, P<10(-14)). Although there was an association between GEP class 2 and monosomy 3 (Fisher exact test, P<0.0001), 54 of 260 tumors (20.8%) were discordant for GEP and chromosome 3 status, among which GEP demonstrated superior prognostic accuracy (log-rank test, P = 0.0001). By using multivariate Cox modeling, GEP class had a stronger independent association with metastasis than any other prognostic factor (P<0.0001). Chromosome 3 status did not contribute additional prognostic information that was independent of GEP (P = 0.2). At 3 years follow-up, the net reclassification improvement of GEP over TNM classification was 0.43 (P = 0.001) and 0.38 (P = 0.004) over chromosome 3 status.
The GEP assay had a high technical success rate and was the most accurate prognostic marker among all of the factors analyzed. The GEP provided a highly significant improvement in prognostic accuracy over clinical TNM classification and chromosome 3 status. Chromosome 3 status did not provide prognostic information that was independent of GEP.
Purpose
To define, describe, and illustrate a previously unreported category of discrete melanotic choroidal melanocytic lesion.
Methods
Prospective ophthalmoscopic study of the ocular fundi of 79 ...light-skinned persons 50 years of age or older not referred for any evident fundus lesion, with detection of all evident discrete melanotic choroidal lesions > 0.3 mm in largest basal diameter.
Results
One or more discrete dark-brown to gray choroidal lesions > 0.3 mm in largest basal diameter were detected in 27 of the 79 evaluated subjects (34.2%). All but four of the detected lesions were “flat” by both ophthalmoscopy and ultrasonography. A single flat lesion was present in one eye of 14 subjects whose fellow eye was normal, 2 or more flat lesions were evident in one eye of 5 subjects whose other eye was normal, and one or more lesions were evident in both eyes of 6 subjects.
Conclusion
While some of the discrete small, flat melanocytic choroidal lesions detected in this study might have been choroidal nevi, the author hypothesizes that an indeterminate proportion of them may have been focal aggregates of normal or near normal uveal melanocytes (FANNUMs).
Purpose To determine the frequency of discordant gene expression profile (GEP) classification of posterior uveal melanomas sampled at 2 tumor sites by fine-needle aspiration biopsy (FNAB). Design ...Prospective single-institution longitudinal study performed in conjunction with a multicenter validation study of the prognostic value of GEP class of posterior uveal melanoma cells for metastasis and metastatic death. Methods FNAB aspirates of 80 clinically diagnosed primary choroidal and ciliochoroidal melanomas were obtained from 2 tumor sites prior to or at the time of initial ocular tumor treatment and submitted for independent GEP testing and classification. Frequency of discordant GEP classification of these specimens was determined. Results Using the support vector machine learning algorithm favored by the developer of the GEP test employed in this study, 9 of the 80 cases (11.3% 95% confidence interval: 9.0%–13.6%) were clearly discordant. If cases with a failed classification at 1 site or a low confidence class assignment by the support vector machine algorithm at 1 or both sites are also regarded as discordant, then this frequency rises to 13 of the 80 cases (16.3% 95% confidence interval: 13.0%–19.6%). Conclusion Sampling of a clinically diagnosed posterior uveal melanoma at a single site for prognostic GEP testing is associated with a substantial probability of misclassification. Two-site sampling of such tumors with independent GEP testing of each specimen may be advisable to lessen the probability of underestimating an individual patient's prognostic risk of metastasis and metastatic death.
Purpose To evaluate and comment on published peer-reviewed literature for evidence of effectiveness of treatments for metastatic uveal melanoma. Design Analytical nonexperimental study of published ...peer-reviewed data. Methods Literature search and analysis of pertinent articles published between January 1, 1980 and June 30, 2008. Results Of 80 identified publications, 12 (15.0%) were review articles without original information, 2 (2.5%) were review articles combined with case reports, 22 (27.5%) were case reports, 16 (20.0%) were retrospective descriptive case series reports, 3 (3.75%) were pilot studies of a novel intervention, 2 (2.5%) were prospective phase I clinical trials, 8 (10.0%) were prospective phase I/II clinical trials, and 15 (18.75%) were prospective phase II clinical trials. None of the articles reported a prospective, randomized phase III clinical trial. The largest reported unselected patient groups had a median survival of 3 to 4 months after detection of metastasis, whereas the largest selected patient groups showed substantially longer median survival times. Conclusions Although median survival time after diagnosis of metastatic uveal melanoma tends to be substantially longer in selected patient subgroups subjected to aggressive invasive interventions than it is in unselected groups, much if not most of this apparent difference in survival is likely to be attributable to selection bias, surveillance bias, and publication bias rather than treatment-induced alteration of expected outcome. Published peer-reviewed articles do not provide compelling scientific evidence of any survival benefit of any method of treatment for any subgroup of patients with metastatic uveal melanoma.
Abstract Background and purpose Non-homologous end-joining (NHEJ) and homologous recombination (HR) contribute to the repair of irradiation-induced DNA double-strand breaks (DSBs). We investigated ...the impact of the two major DSB repair machineries for cellular survival of human tumor cells in response to proton- and photon-irradiation. Materials and methods DNA damage repair and cell survival were analyzed in wildtype, HR- and NHEJ-repair-compromised and pharmacologically DNA-PKcs-inhibited human tumor cells in response to clinically relevant, low-linear energy transfer proton- and 200-keV photon-irradiation. Results Pharmacological inhibition of DNA-PKcs strongly radiosensitized lung adenocarcinoma and glioblastoma cells to photon- but to a much lower extent to proton-irradiation. Enhanced radiosensitization correlated with strongly delayed repair kinetics with elevated amounts of γH2AX foci after photon-irradiation. Interestingly, we observed reduced phosphorylation of DNA-PKcs at Ser-2056 and Thr-2609 clusters after proton-irradiation compared to photon-irradiation. In contrast, A549 cells depleted of the RAD51 recombinase were markedly hypersensitive to proton-irradiation in comparison with control cells. Likewise, human BRCA2-deficient ovarian carcinoma cells were hypersensitive toward proton- in comparison with photon-irradiation. Conclusion A differential DNA damage response with enhanced susceptibility of HR-deficient tumor cells to proton-irradiation and increased sensitivity of photon-irradiated tumor cells to NHEJ inhibitors were demonstrated.
We report the case of a 9-month-old girl with bilateral retinoblastoma who had incomplete tumor resolution after selective ophthalmic artery infusion chemotherapy (SOAIC). Systemic chemotherapy, ...rarely used as salvage therapy after SOAIC, with systemic carboplatin, etoposide, and vincristine achieved complete and sustained regression in both eyes.
Determine which posterior uveal melanoma (PUM) size classification with three categories has the best prognostic discrimination.
Single-institution study of 424 consecutive patients with PUM. The ...tumor's largest basal diameter (LBD), smallest basal diameter (SBD), and thickness (TH) were estimated by fundus mapping and ultrasonography. Tumors were assigned to "small," "medium," or "large" size categories defined by 11 different classifications (Linear LBD, Rectangular LBD × TH, Cubic LBD × SBD × TH, Warren Original, Warren Modified, Augsburger, COMS Original, COMS Revised, TNM 2002, and modified TNM 2010 classification a,b). Prognostic significance of classifications was evaluated by Kaplan-Meier event curves with computation of log rank test for trend statistic.
In six classification systems (Warren Original, Warren Modified, COMS Revised, TNM 2002, TNM 2010a, TNM 2010b) >50% of tumors fell within one subgroup. In the Warren Original classification <5% of tumors fell within one subgroup. Separation of Kaplan-Meier curves among three size categories was judged "excellent" in four classifications (Linear LBD, Cubic Volume, TNM 2010a, and TNM 2010b) and "very poor" in the Warren Original. Linear LBD classification was associated with highest log rank statistic value. TNM 2010a, TNM 2010b, TNM 2002, Augsburger, and Cubic Volume classifications were also determined to be quite good.
Linear LBD classification was the best three-size category discriminator among low-, intermediate-, and high-risk subgroups. Considering our findings, it seems possible that the arduous work required to apply complex classifications, especially for three-category systems, for PUM may not be justified in routine clinical practice.
Purpose To determine whether any conventional clinical prognostic factors for metastasis from uveal melanoma retain prognostic significance in multivariate models incorporating gene expression ...profile (GEP) class of the tumor cells. Design Prospective, interventional case series with a prognostic model. Methods Single-institution study of GEP testing and other conventional prognostic factors for metastasis and metastatic death in 299 patients with posterior uveal melanoma evaluated by fine-needle aspiration biopsy (FNAB) at the time of or shortly prior to initial treatment. Univariate prognostic significance of all evaluated potential prognostic variables (patient age, largest linear basal diameter of tumor LBD, tumor thickness, intraocular location of tumor, melanoma cytomorphologic subtype, and GEP class) was performed by comparison of Kaplan-Meier event rate curves and univariate Cox proportional hazards modeling. Multivariate prognostic significance of combinations of significant prognostic factors identified by univariate analysis was performed using step-up and step-down Cox proportional hazards modeling. Results GEP class was the strongest prognostic factor for metastatic death in this series. However, tumor LBD, tumor thickness, and intraocular tumor location also proved to be significant individual prognostic factors in this study. On multivariate analysis, a 2-term model that incorporated GEP class and largest basal diameter was associated with strong independent significance of each of the factors. Conclusion Although GEP test is the most robust prognostic indicator in uveal melanoma and early studies of mostly larger tumors found that no clinicopathologic factors had significant prognostic value independent of GEP, our single-center study, which included a substantial proportion of smaller tumors, showed that both GEP and LBD of the tumor are independent prognostic factors for metastasis and metastatic death in multivariate analysis.
Valid biomarkers of motor system function after stroke could improve clinical decision-making. Electroencephalography-based measures are safe, inexpensive, and accessible in complex medical settings ...and so are attractive candidates. This study examined specific electroencephalography cortical connectivity measures as biomarkers by assessing their relationship with motor deficits across 28 days of intensive therapy. Resting-state connectivity measures were acquired four times using dense array (256 leads) electroencephalography in 12 hemiparetic patients (7.3 ± 4.0 months post-stroke, age 26-75 years, six male/six female) across 28 days of intensive therapy targeting arm motor deficits. Structural magnetic resonance imaging measured corticospinal tract injury and infarct volume. At baseline, connectivity with leads overlying ipsilesional primary motor cortex (M1) was a robust and specific marker of motor status, accounting for 78% of variance in impairment; ipsilesional M1 connectivity with leads overlying ipsilesional frontal-premotor (PM) regions accounted for most of this (R(2) = 0.51) and remained significant after controlling for injury. Baseline impairment also correlated with corticospinal tract injury (R(2) = 0.52), though not infarct volume. A model that combined a functional measure of connectivity with a structural measure of injury (corticospinal tract injury) performed better than either measure alone (R(2) = 0.93). Across the 28 days of therapy, change in connectivity with ipsilesional M1 was a good biomarker of motor gains (R(2) = 0.61). Ipsilesional M1-PM connectivity increased in parallel with motor gains, with greater gains associated with larger increases in ipsilesional M1-PM connectivity (R(2) = 0.34); greater gains were also associated with larger decreases in M1-parietal connectivity (R(2) = 0.36). In sum, electroencephalography measures of motor cortical connectivity-particularly between ipsilesional M1 and ipsilesional premotor-are strongly related to motor deficits and their improvement with therapy after stroke and so may be useful biomarkers of cortical function and plasticity. Such measures might provide a biological approach to distinguishing patient subgroups after stroke.
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